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Untitled
Table of contents
Foreword from AFTC...............................................................................................................................................5
Foreword from WEFTA............................................................................................................................................6
Welcome address....................................................................................................................................................7
Committees
TAFT Organizing Committee.........................................................................................................................8
TAFT Scientific Committee............................................................................................................................8
WEFTA Core member institutes and contact persons...................................................................................9
AFTC Executive Committee..........................................................................................................................9
2006 Earl P. McFee Award Committee..........................................................................................................9
Sponsors...............................................................................................................................................................11
Complete conference program..............................................................................................................................13
Oral presentations
Advances in processes and added value of products.................................................................................21
Functional, innovative and convenient seafood and ingredients.................................................................55
Aquaculture and fish supply........................................................................................................................65
Consumers, market and sea products........................................................................................................77
Seafood, marine ingredients and health.....................................................................................................85
New concepts to minimize seafood associated risks................................................................................105
Posters
Advances in processes and added value of products...............................................................................123
Seafood, marine ingredients and health...................................................................................................153
New concepts to minimize seafood associated risks................................................................................159
Functional, innovative and convenient seafood and ingredients...............................................................169
Consumers, market and sea products......................................................................................................177
Aquaculture and fish supply......................................................................................................................179
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
Page blanche
intentionnelle
From AFTC
L
Foreword
ong before the French expedition led by Jacques Cartier landed in Gaspé, Basque fishermen had been
fishing for cod in the Gulf of St. Lawrence. These wise entrepreneurs provided a part of Europe with
one of the most valuable marine resources at the time while keeping the origin of their wealth secret.
Centuries later, people from Nouvelle France and New England took over the Basque fishery and consolidated
the triangular trade that ensured new colonies and the “old countries” of Europe of a secure access to cheap
protein sources. This fishing industry played a significant role in the social and economic development of both
worlds, old and new. For example, from 1768 to 1772, fish accounted for 35 percent of New England’s total
export revenue. Two hundred years later – in 1992 to be specific – when I began a postdoctoral fellowship on
cod muscle post-mortem biochemistry in Halifax, the cod were gone…Today fishery technologists and scientists have a crucial responsibility: transforming what used to be considered as an abundant, easily available
and cheap resource into high-value products that can no longer, and in any way, be wasted. The health benefits
associated with the consumption of seafood are increasingly becoming a key element for adding value and
marketing marine products. AFTC is therefore extremely proud to welcome you to Québec City, one of the first
European settlements in North America, and to this international event organised jointly by AFTC and WEFTA.
We are confident that this symposium will contribute significantly to a new, wealthy, healthy and sustainable
fishing industry.
De l’AFTC
B
Avant-propos
ien avant que Jacques Cartier, représentant du roi de France, ne pose les pieds sur la péninsule gaspésienne, les pêcheurs basques sillonnaient le golfe Saint-Laurent en quête de morue. Ce peuple d’entrepreneurs fournissait à une bonne partie de l’Europe une des ressources marines les plus précieuses
à l’époque, et ce en prenant grand soin de ne pas révéler les sites de pêche qui leur assuraient de tels bénéfices. Quelques siècles plus tard les occupants de la Nouvelle-France et de la Nouvelle-Angleterre ont pris le
relais des pêcheurs basques et ont établi le célèbre commerce triangulaire qui a entre autres permis de fournir
à la fois en Europe et aux nouvelles colonies des sources fiables et très bon marché de protéines de qualité.
Cette industrie des pêches a joué un rôle prépondérant dans le développement social et économique de l’ancien et du nouveau monde. Par exemple, de 1768 à 1772, les produits de la pêche constituaient 35 % des
revenus d’exportation de la Nouvelle-Angleterre. Quelque deux cents ans plus tard, en 1992 pour être exact,
lorsque je débutai un stage postdoctoral à Halifax sur la biochimie post-mortem des protéines musculaires de
la morue, celles-ci avaient pratiquement disparu des eaux canadiennes… Aujourd’hui, les scientifiques et les
technologistes des produits de la pêche ont une énorme responsabilité : transformer ce qui a été longtemps
perçu comme étant une ressource abondante, disponible et bon marché en des produits haut de gamme ou
de grande valeur qui ne peuvent supporter aucun gaspillage. L’argument « santé » associé à la consommation
des produits marins devient de plus en plus un élément clé de la valeur ajoutée et des stratégies de mise en
marché de ces derniers. L’AFTC est donc très fière de vous accueillir dans la ville de Québec, un des premiers sites de colonisation européenne en Amérique du Nord, ainsi qu’à cet événement international organisé
conjointement par l’AFTC et le WEFTA. Nous sommes convaincus que ce symposium contribuera de façon
significative à l’émergence d’une nouvelle industrie des pêches, à la fois saine, prospère et renouvelable.
Pierre U. Blier
AFTC
Scientific Program Committee representative
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
From WEFTA
T
Foreword
he second Trans-Atlantic Fisheries Technology Conference is becoming a reality. Again, the fruitful
collaboration between two independent organisations, the Atlantic Fisheries Technology Conference
(AFTC), based in North America, and the West European Fish Technologists’ Association (WEFTA),
based in Europe, has resulted in a conference with highly relevant topics for both organisations. The experience from the first TAFT conference three years ago was that new contacts, networks and friendships were
created. Communication over large distances have become better and faster with the electronic development making Internet and e-mail exchange a convenient way of talking together. However, it is still necessary
to meet in order to keep up the contacts and to introduce new members in the society across the Atlantic. The
main headline for the TAFT 2006 conference is ‘Health and Innovative Products from the Sea’. This is very
relevant at a time where the positive health elements of seafood consumption is becoming more and more
evident for consumers all over the world, and at the same time we observe an industry being aware of the
importance of the innovative products requested by the market. When composing the programme only the
keynote presentations were invited. It is a pleasure to observe how well the voluntary papers matched the
topics listed such that a coherent programme could be presented. Anyone having organised a conference
knows how much work there is involved. When looking at the magnificent programme for the TAFT 2006 it
is clear that it must have been a tremendous job to pull it all together. So it is only for me to congratulate the
Canadian Organising Committee with the outstanding work performed and the great result obtained! I wish
you all a successful conference.
Du WEFTA
L
Avant-propos
e second Trans-Atlantic Fisheries Technology Conference prend désormais forme. Une fois encore, la
collaboration étroite entre deux organisations indépendantes - l’Atlantic Fisheries Technology Conference (AFTC), nord-américaine et la West European Fish Technologists’ Association (WEFTA), sa
vis-à-vis européenne – permet de livrer une rencontre proposant des sujets chers aux deux organisations.
La première expérience du TAFT, il y a déjà trois ans, avait servi à créer de nouveaux contacts, de nouveaux
réseaux et aussi de nouvelles amitiés. Le travail à distance et les échanges se sont multipliés, facilités par
les puissants réseaux de communication que sont Internet et le courriel mais les rencontres demeurent essentielles pour maintenir des liens forts et initier de nouvelles rencontres par delà l’océan. Cette année, le
thème « Santé et produits innovateurs issus de la mer » m’apparaît d’autant plus important à une époque
où les avantages que procurent la consommation des produits aquatiques deviennent plus évidents chaque
jour dans tous les pays du monde et à un moment où les entreprises considèrent avec intérêt l’innovation
en ce domaine. Au début de l’élaboration du programme, quelques conférenciers de marque ont été invités.
J’ai été ravi de constater à quel point les propositions de présentations orales et d’affiches scientifiques ont
permis la préparation d’un programme complet et cohérent avec les thèmes de la conférence. Ceux qui ont
déjà participé à la préparation d’un tel événement savent ce qu’il faut investir en énergie et en temps. Le
remarquable programme qui nous est proposé au TAFT 2006 fait preuve de nombreux efforts déployés par
l’équipe de cette année. C’est pourquoi il me fait plaisir d’offrir mes plus sincères félicitations aux membres
du Comité organisateur avec la conviction que leur travail a porté fruit. Je vous souhaite une excellente
conférence.
Torger Børresen
WEFTA Association
Scientific Program Committee representative
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
Welcome to Québec City
F
Welcome!
rom the very first, the organising committee of the second joint Trans-Atlantic Fisheries Technology (TAFT
2006) conference committed itself to holding this event with the conviction that support would be tremendous. And indeed, it has been. In no time at all, perfect mutual chemistry evolved among committee members
representing four of Québec’s major research and development organisations: the Université du Québec à
Rimouski, Centre de recherche sur les biotechnologies marines, Institut des nutraceutiques et des aliments
fonctionnels and Ministère de l’Agriculture, des Pêcheries et de l’Alimentation. The scientific advisory committee, whose members represent WEFTA and AFTC, worked unstintingly to lay down the foundations of a truly
collaborative conference. We must also underline the enthusiasm of researchers and authors, who responded
in great number to our invitation to participate in a sustained and fascinating program. Our funding partners
were equally convinced that this international event would serve to build essential ties among innovative actors in the marine product field; we thank them for their unwavering support. The early signs that a great many
people would be attending TAFT 2006 were a source of continual motivation to us and today, we are delighted
and honoured to welcome all of you to Québec City. We hope you will enjoy discovering and rediscovering historic Québec City through the highly original social activities we have planned for you, including tours, music,
Canadian art, and legends... and even a few ghosts! Enjoy the conference!
Bienvenue à Québec
D
Bienvenue!
ès le début des travaux, le comité organisateur de la deuxième conférence conjointe Trans-Atlantic Fisheries Technology (TAFT 2006) s’est engagé à tenir l’événement avec la conviction que ses appuis seraient
nombreux. Ils l’ont été. Une parfaite chimie s’est vite fait sentir entre les membres de quatre grandes organisations de recherche et développement du Québec : l’Université du Québec à Rimouski, le Centre de recherche
sur les biotechnologies marines, l’Institut des nutraceutiques des aliments fonctionnels ainsi que le Ministère
de l’Agriculture, des Pêcheries et de l’Alimentation. Les membres du comité scientifique aviseur formé de
représentants du WEFTA et de l’AFTC ont travaillé intensément pour jeter les bases d’un colloque authentiquement conjoint. Retenons aussi l’enthousiasme des chercheurs et des auteurs, nombreux à répondre à
notre invitation pour proposer un programme soutenu et captivant. Nos partenaires financiers ont également
été convaincus que cet événement d’envergure internationale permettait de créer des liens essentiels entre les
acteurs de l’innovation dans le domaine des produits marins; nous les remercions de leur appui indéfectible.
Les signes annonçant une participation importante au TAFT 2006 nous ont toujours motivés. Nous sommes
ravis et honorés de vous accueillir aujourd’hui en grand nombre à Québec. Nous espérons que vous prendrez
plaisir à découvrir et à redécouvrir la ville historique de Québec à travers les activités sociales fort originales
que nous vous proposons sous forme de visites, de musique, d’art canadien, de légendes... et de fantômes!
Bon colloque!
Luc Leclerc
TAFT 2006 Organizing Chair
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
Committees
TAFT Organizing Committee
Luc LECLERC (Chair organization)
Ministère de l’Agriculture, des Pêcheries et de l’Alimentation (MAPAQ)
Sophie BANVILLE
Université Laval, Institut des nutraceutiques et des aliments fonctionnels
(INAF)
Ismail FLISS
Université Laval, Institut des nutraceutiques et des aliments fonctionnels
(INAF)
Alain GUILLOU
Centre de recherche sur les biotechnologies marines (CRBM)
Lucie BEAULIEU
Université du Québec à Rimouski (UQAR)
Ginette LEVESQUE
Ministère de l’Agriculture, des Pêcheries et de l’Alimentation (MAPAQ)
Pierre BLIER (Chair, Scientific)
Université du Québec à Rimouski (UQAR)
Marcel LÉVESQUE
Université du Québec à Rimouski (UQAR)
Julie BOYER
Ministère de l’Agriculture, des Pêcheries et de l’Alimentation (MAPAQ)
Marc VEILLET
Ministère de l’Agriculture, des Pêcheries et de l’Alimentation (MAPAQ)
Michel DESBIENS
Ministère de l’Agriculture, des Pêcheries et de l’Alimentation (MAPAQ)
TAFT Scientific Committee
Pierre BLIER
Université du Québec à Rimouski (UQAR)
Torger BØRRESEN
Danish Institute for Fisheries Research (DIFRES)
Lucie BEAULIEU
Université du Québec à Rimouski (UQAR)
Françoise LEROI
Institut français de recherche pour l’exploitation de la mer (Ifremer)
Ismail FLISS
Institut des nutraceutiques et des aliments fonctionnels (INAF)
Joop LUTEN
Netherlands Institute for Fisheries Research (RIVO)
Tom GILL
Canadian Institute of Fisheries Technology (CIFT)
Joerg OEHLENSCHLÄGER
Federal Research Centre for Nutrition and Food (FRCNF)
Hordur KRISTINSSON
University of Florida
Guðrún Ólafsdóttir
Icelandic Fisheries Laboratories (IFL)
Denise SKONBERG
University of Maine
Richard WATSON
Sea Fish Industry Authority
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
WEFTA Core member institutes and contact persons
Joop B. Luten
Torger Børresen
Joerg Oehlenschläger
Hartmut Rehbein
Sjöfn Sigurgísladóttir
Richard Watson
Susanna Airaksinen
Maria Leonor Nunes
Karen Bekaert
A. Javier Borderias
Ingrid Undeland
Piotr J. Bykowski
Even Stenberg
Luçay Han-Ching
Nikolaos Soultos
John Fagan
Horald Joensen
Bianca Maria Poli
Sukran Cakli
Netherlands Institute for Fisheries Research (RIVO), IJmuiden, The Netherlands
Danish Institute for Fisheries Research (DIFRES), Lyngby, Denmark
Federal Research Centre for Nutrition and Food (FRCNF), Hamburg, Germany
Federal Research Centre for Nutrition and Food (FRCNF), Hamburg, Germany
Icelandic Fisheries Laboratories, Reykjavik, Iceland
Sea Fish Industry Authority, Hull, United Kingdom
Finnish Game and Fisheries Research Institute,Turku, Finland
Instituto de Investigação das Pescas e do Mar (IPIMAR), Lisboa, Portugal
Institute for Agricultural and Fisheries Research, Oostende, Belgium
Instituto del Frio (CSIC), Madrid, Spain
Chalmers University of Technology, Göteborg, Sweden
Sea Fisheries Institute, Gdynia, Poland
Norwegian Institute of Fisheries and Aquaculture Research (Fiskeriforskning), Tromsø, Norway
Institut Français de Recherche pour l’Exploitation de la Mer (IFREMER), Nantes, France
University of Thessaloniki, Thessaloniki, Greece
Irish Sea Fisheries Board (BIM), Dublin, Ireland
Food, Veterinary and Environmental Agency, Tórshavn, Faroe Islands
University Firenze, Florence, Italy
Ege University, Izmir, Turkey
AFTC Executive Committee
Newfoundland
A. Collins Onodenalore, Memorial University of Newfoundland, St. John’s, Newfoundland, Canada
Fereidoon Shahidi, Memorial University of Newfoundland, St. John’s, Newfoundland, Canada
The Maritimes
Andy Woyewoda, National Research Council, Halifax, Nova Scotia, Canada
Tom Gill, CIFT, Dalhousie University, Halifax, Nova Scotia, Canada
Québec
Pierre Blier, Université du Québec à Rimouski, Rimouski, Québec, Canada
Luc Leclerc, Centre technologique des produits aquatiques, Gaspé, Québec, Canada
New England
Lori Pivarnik, University of Rhode Island, FSN Center, West Kingston, RI USA
Denise Skonberg, University of Maine, Orono, ME USA
Central Atlantic
Doris Hicks, University of Delaware, Lewes, DE USA
Ken Gall, Cornell University, N.Y. Sea Grant Extension, Coram, NY USA
South Atlantic
Hordur G. Kristinsson, University of Florida, Gainesville, FL USA
David P. Green, North Carolina State University, CMST, Morehead City, NC USA
Ex-officio Committee Members
Joe Regenstein (Executive Secretary), Cornell University, Ithaca, NY USA
Steven Otwell (SST), University of Florida, Gainesville, FL USA
Torger Børresen (WEFTA), Danish Institute for Fisheries Research, Lyngby, Denmark
Gudrun Ólafsdóttir (WEFTA), Icelandic Fisheries Laboratory, Reykjavik, Iceland
George J. Flick (2005 Conference Chair), Virginia Tech, Blacksburg, VA USA
Michael L. Jahncke (2005 Conference Secretary), Virginia Seafood Agricultural Research and Extension Center, Hampton, VA USA
2006 Earl P. McFee Award Committee
Torger Børresen (Chair), Danish Institute for Fisheries Research, Lyngby, Denmark
Luc Leclerc, Centre technologique des produits aquatiques, Gaspé, Québec, Canada
Robert Collette, National Fisheries Institute, Inc., McLean, VA USA
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
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Many thanks to our sponsors:
Fisheries and Oceans
Canada
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
Pêches et Océans
Canada
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Complete Program
Complete Conference Program
Sunday, October 29th
13:00 Visit to Institute of Nutraceuticals and Functional Foods (INAF)/Institut des nutraceutiques et des aliments fonctionnels (INAF)
17:00 Opening reception - room Place Montcalm
Monday, October 30th – room Borduas
AM
8:30 Opening address
Advances in processes and added value of products
Sponsored by Ministère de l’Agriculture, des Pêcheries et de l’Alimentation, Québec
Chairs : Hordur G. Kristinsson and Ingrid Undeland
8:50 Keynote lecture – C. Barrow – Ocean Nutrition Canada ltd
Stabilization and formulation of shelf-stable healthy food ingredients fortified with omega-3 oils from fish
9:20 Chabeaud A.*, Dutournie P., Guérard F., Vandanjon L., Bourseau P.
Optimization of the production of antioxidant peptides from Saithe (Pollachius virens) hydrolysate
9:40 Dybvik A.I., Rustad T., Falch E.*
Solid phase micro extraction as a tool to isolate lipid classes and deterioration of marine lipids
10:00Break
10:30Dumay J.*, Barnathan G., Jaouen P., Bergé J.P.
Mild procedure for obtaining lipidic and peptidic fractions from sardine (Sardina pilchardus) heads
10:50Cakli S., Kisla D., Ataman C., Dincer T.*, Kelesoglu S., Cadun A., Kes M.
Application of chitosan and its phosphate derivatives for quality preservation of fish stored at refrigerator temperature
11:10 Wright B.J., Pope W.W., Johnston D.A., Lanier T.C.*
Impacts of protein dispersion on fish muscle protein gelation
11:30 Aider M.*, Arul J., Mateescu A.M., Brunet S., Bazinet L.
Electro-separation of chitosan oligomers by electrodialysis with ultrafiltration membrane (EDUF)
11:35 Bechtel P.J.*, Sathivel S., Oliveira A.C.M.
Production and characterization of alkali extracted protein powders from pollock and salmon heads
11:40 Nolsøe H.*
Study of gel strength improvement of alkaline processed surimi of Blue whiting
11:45 Plante S.*, Oliveira A.C.M., Sreenivasan A., Smiley S., Bechtel P.J.
Protein powders from fish processing byproducts
11:50 Pires C., Batista I., Godinho V., Nunes M.L.*
Functional and biochemical characterization of proteins remaining in solution after isoelectric precipitation
12:00Lunch - L’Astral Restaurant/Loews Le Concorde
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
13
Monday, October 30th – room Borduas
PM
Advances in processes and added value of products (continuation)
Sponsored by Ministère de l’Agriculture, des Pêcheries et de l’Alimentation, Québec
Chairs : David P. Green and Begoñia Pérez Villarreal
13:30Keynote lecture – M. Balaban – University of Florida
Processing, adding value, and quality of aquatic foods
14:00Bocker U.*, Aursand I., Veliyulin E., Kohler A., Ofstad R.
FT-IR microspectroscopy: investigation of changes in microstructure and muscle proteins due to salting in Atlantic salmon of different
raw quality
14:20Suklim K., Flick G.*
The effect of high hydrostatic pressure on the microbiological, physical, and sensory quality of fresh blue crab (Callinectes sapidus)
meat
14:40Andersen E., Christensen L., Christensen M., Baron C.P.*
Correlations between protein oxidation and texture during ripening of old fashion marinated herrings
15:00 Ramaswamy H.
High processing of seafood for shelf-life extension, assuring safety and improve quality
15:20 - 16:10 Poster Session #1 - room Lemieux
16:10Nilsen H*, Heia K., Sivertsen A.H.
Fish fillet inspection – quality control by imaging spectroscopy
16:30Oliveira A.C.M.*, Crapo C., Himelbloom B.H., Morey A., Ambardekar A.
Development and characterization of vacuum packaged wild pink salmon (Oncorhynchus gorbuscha) jerkies using marinades
16:50Pestana C.*, Gonçalves A., Mendes R.
Effect of soluble gas stabilization and modified atmosphere packaging on the quality of sardine fillets (Sardina pilchardus)
16:55Alfaro A., Prentice C.*
Processing optimization and determination of functional properties of gelatine from King weakfish (Macrodon ancylodon) bones
17:00Felberg H.S.*, Nunes M.L., Batista I., Martinez I.
Gelatine degrading enzyme activities in herring (Clupea harengus) and sardine (Sardina pilchardus) – the search for causative
enzymes of belly bursting
Social activities
17:30Ghost Tour in Old Quebec
or
18:15Visit at the Musée national des beaux-arts du Québec
19:45Cocktail dinner at the Musée national des beaux-arts du Québec
Tuesday, October 31st – room Borduas
AM
Advances in processes and added value of products (continuation)
Sponsored by Ministère de l’Agriculture, des Pêcheries et de l’Alimentation, Québec
Chairs : George J. Flick and Heidi Nilsen
8:30 Eymard S.*, Baron C.P., Jacobsen C.
Evaluation of oxidative stability during processing and storage of fatty fish mince
8:50 Hultin H.O.
Some practical observations on lipid oxidation in postmortem fish muscle
14
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
9:10 Ólafsdóttir G.*, Jónsdóttir R., Bragadóttir M.
The role of volatile compounds in odor development during haemoglobin-mediated oxidation of cod muscle membrane lipids
9:30 Alfaro B.*, Nuin M., Pin C., Le Marc Y.
« Fish shelf life prediction program » (FSLP) a tool for predicting the shelf life of fresh fish
9:50 Birkeland S.*, Akse L., Skara T.
Quality aspects of injection-salted and cold-smoked pre-rigor Atlantic salmon (Salmo salar) fillets
10:10Break
10:40 Herland H.*, Esaiassen M., Olsen R.L.
Muscle quality and storage stability of farmed Cod (Gadus morhua L.)
11:00 Kjærsgård I.*, Nørrelykke M.R., Baron C.P., Jessen F.
Protein oxidation of rainbow trout muscle during frozen storage and identification of carbonylated proteins
11:20 Gornik S.*, Albalat A., Neil D.M., Coombs, G.H.
Post-mortem changes in Norway lobster (Nephrops norvegicus) – possible reasons for the absence of the rigor-mortis state and the
relative short shelf life
11:40 Lempek T., Prentice C.*
Rheology of surimi-based products from fatty fish underutilized by the industry: Argentine croaker (Umbrina canosai, Berg 1985)
11:45 Albalat A.*, Gornik S., Crozier A., Atkinson R.J.A., Coombs G.H., Neil D.M.
Effects of different capture methods on nucleotide breakdown products in Norway lobster (Nephrops norvegicus) and possible
consequences for quality
11:50 Veiseth E.*, Tingbø M.G., Ofstad R., Hannesson K.O.
The muscle extracellular matrix proteome of Atlantic cod and Spotted wolffish
12:00Lunch - room Place Montcalm
Tuesday, October 31st – room Borduas
PM
Functional, innovative and convenient seafood and ingredients
Sponsored by Université du Québec à Rimouski
Chairs : Guðrún Òlafsdóttir and Lucie Beaulieu
13:30Keynote lecture – A. Marette – Université Laval
Uncovering bioactive ingredients in fish : beneficial effects on obesity-linked insulin resistance and diabetes
14:00Børresen T.
Future priorities of research for healthy, safe and nutritious seafood based on results from Seafood plus
14:20Smith J.*, McLean C.H.
Antioxidant activity of seaweed extracts in oil
14:40 - 15:30 Poster session #2 - room Lemieux
15:30Lee C.*, Joaquin H., Lee K.H., Oliveira A.C.M.
Development strategy for high omega-3 fatty acid seafood products using fish mince
15:50Borderias J.*, Sánchez-Alonso I., Jiménez-Escrig A., Saura-Calixto F., Larsson K., Undeland I.
Antioxidant protection of minced fish muscle by white grape pomace
16:10Baxter S.*, Skonberg D.
Use of protein additives in gels from previously cooked Jonah crab (Cancer borealis) minced meat
16:30Helgason T., Weiss J., McClements D.J., Gislason J., Einarsson J.M., Kristbergsson K.*
The effect of molecular characteristics of chitosan on its ability to bind fat in an in vitro simulation model for digestion
16:50Cardoso C., Mendes R., Pedro S., Nunes M.L.*
Storage stability of frankfurter hake sausages enriched in fiber
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
15
Tuesday, October 31st – room Leduc
AM
Aquaculture and fish supply
Sponsored by Société de développement de l’industrie maricole
Chairs : Denise Skonberg and Flemming Jessen
9:00 Keynote lecture – G. Bell – University of Stirling
Sustainable aquafeeds for the provision of safe and nutritious aquaculture
9:30 Hagen O.*, Johnston I.A., Solberg C.
Implication of collagen and hydroxylysyl pyridinoline cross-link compartments on the texture of Atlantic halibut (Hippoglossus
hippoglossus L.) muscle
9:50 Nielsen J.*, Loje H.
Influence of technological parameters, fat content and size on liquid leakage in cold-smoked salmon
10:10Break
10:40Stone D.*, Hardy R.W.
Fish size influences the digestibility and availability of nutrients from a potential alternative lipid source, Natunola omega-3 de-hulled
flax kernel, by rainbow trout, Oncorhynchus mykiss (Walbaum)
11:00 Leth N.K., Hyldig G., Jensen K.N., Jessen F.*
Proteomics, sensory profiling and multivariate data analysis to find biomarkers: Inclusion of eating quality in breeding programs of
rainbow trout (Oncorhynchus mykiss)
11:20 Buckley M.K.
Live delivery of wild Alaska salmon and its effects on seafood quality
11:40 LeFrançois N.
The culture of the « rock crusher » : Innovative and high-value products from wolffish aquaculture
12:00Lunch - room Place Montcalm
Tuesday, October 31th – room Leduc
PM
Aquaculture and fish supply (continuation)
Sponsored by Société de développement de l’industrie maricole
13:30Eikevik T.M.*, Magnussen O.M.
Processing of zooplankton – Calanus finmarchicus – as raw material for fish feed
13:50Airaksinen S.*, Aro T., Ruohonen K.
Chilling before slaughter as a tool to reduce stress and to improve product quality
14:10Solberg C.
Improved quality with restricted feeding of Atlantic salmon
14:15 - 15:30 Poster session #2 - room Lemieux
16
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
Consumers, market and sea products
Sponsored by Agri-Food Export Group/Groupe Export agroalimentaire
Chairs : Joop B. Luten and Ginette Levesque
15:30Keynote lecture - M. Sirois - Fishery Products/Ocean Cuisine International
Proven methods of developing successful new value added seafood products in an ever changing market place
16:00Lindkvist K.B., Gallart Jornet L.*
Spanish salt fish market in change
16:20Pardo M.A.*, Zarraonaindia I., Rendo F., Iriondo M., Estonba A.
Authentication of the European anchovy from the Biscay Bay: An approach based on the use of molecular techniques
16:40Rehbein H.
Differentiation of raw or canned Atlantic herring (Clupea harengus), sprat (Sprattus sprattus) and Sardine species by PCR-RFLP and
PCR-SSCP
16:45Cakli S.*, Cadun A., Dincer T.
Traditional fish and fishery products of Turkey
16:50Gallart Jornet L., Escriche I., Barat J.M.*, Fito P.
Salted fish products within the Mediterranean diet. Innovative and traditional products to adapt the new consumer and market trends
Social activity
19:00Conference Banquet and McFee Award presentation
Sponsored by Ministère du Développement économique, de l’Innovation et de l’Exportation, Québec
Wednesday, November 1st – room Leduc
AM
Seafood, marine ingredients and health
Sponsored by Marine Biotechnology Research Center/Centre de recherche sur les biotechnologies marines
Chairs : Joerg Oehlenschläger and Ismail Fliss
9:00
9:30
Keynote lecture – J.P. Bergé – Ifremer
The French network SEApro: a solution to a better fish wastes management?
Testi* S., Gatta P. P., Bonaldo A., Foschi C., Fagioli P., Fusaroli S., Badiani A.
Chub and horse mackerel from the Southern Adriatic Sea as sources of n-3 PUFA
9:35 Nunes M.L.*, Afonso C., Leitão M., Bandarra N.M., Lourenço H.M., Martins M.F., Cas M.
Cholesterol and fatty acid profile of some fish species caught off North Atlantic Ocean, Portugal
9:40 Gatta P.P., Testi* S., Bonaldo A., Silvi M., Ghidini S., Badiani A.
Multielemental analysis of raw and cooked flesh from two underutilised fish species
9:45 Lourenço H.M., Anacleto P., Afonso C., Martins M.F., Lino A.R., Nunes M.L.*
Nutritional composition and some contaminants metals in cephalopods
9:50 Okada T., Morrissey M.*
Production of omega-3 polyunsaturated fatty acid concentrate from sardine oil using immobilized lipase
10:10Poli B.M.*, Abbate R., Parisi G., Gori A.M., Sofi F., Mannini L., Giorgi G.
Sea bass healthy eating quality for consumers needs: in vivo fillet lipid quantity/quality estimation and intake effect on circulating
markers of atherosclerosis
10:30Break
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
17
10:50Tejada M.*, Solas M.T., Navas A., Mendizábal A.
Study of live and frozen anisakis larvae treated with pepsin
11:10 Guérard F.*, Chabeaud A., Laroque D., Denes A., Vandanjon L., Bourseau P., Jaouen P., Thorkelsson G.
Towards the development of marine bio-ingredients with antioxidant properties: a case study
11:30 Arboleya J.C.*, Moreno J., Sanmartín E., Villamiel M., Wilde P.J.
Improving functional properties of tuna by-products by non-enzymatic glycosylation
11:50 Mamelona J., Pelletier E.*, Girard-Lalancette K., Legault J., Karboune S., Kermasha S.
Phenolic content and antioxidant capacity of extracts from sea cucumber, Cucumaria frondosa
12:00 Lunch and Student Awards Presentation - room Place Montcalm
Sponsored by UQAR, INAF, ABK Gaspésie inc. and Oceanova Biotechnologies inc.
Wednesday, November 1st – room Leduc
PM
Seafood, marine ingredients and health (continuation)
Sponsored by Marine Biotechnology Research Center/Centre de recherche sur les biotechnologies marines
14:00Undeland I.*, Sandberg A-S., Sannaveerappa T., Lindquist H., Larsson B.M., Lönn, M.B, Holmäng A.
Role of herring mince, herring oil and herring “press juice” in counteracting negative health effects in rats caused by a cafeteria-style
Western diet
14:20Valdimarsson G.*, Elvevoll E.
Risks and benefits of seafood consumption: Can they be balanced in a meaningful way?
14:40Kristinsson H.*, Theodore A.E., Petty H.T., Raghavan S.
Bioactive properties of protein hydrolysates products from Channel catfish protein isolate
15:00Doucet E.*, Gill T.
Chitosan-based delivery of protamine to food systems through nanoencapsulation
15:20Llanio Villate M.*, Fernández, M.D., Cabrera, B., Bermejo, P., Abad, M.J., Payá, M., Alcaraz M.J.
Stypopodium zonale: a marine algae with anti-inflammatory, analgesic and anti-oxidant effects
15:40Bandarra N.M.*, Monteiro M., Parreira R., Paulo M.C., Andrade A.M., Gisladóttir E., Martinez J., Parra L., Kiely M., Thorsdóttir I.
Erythrocyte membrane fatty acid incorporation as a marker of fish diet in young overweight europeans
16:00TAFT 2006 Closing Address in room Lemieux
Wednesday, November 1st – room Lemieux
AM
New concepts to minimize seafood associated risks
Sponsored by Fisheries and Oceans Canada/Pêches et Océans Canada
Chairs : Tom Gill and Françoise Leroi
9:00 Keynote lecture – F. Dufresne – Université du Québec à Rimouski
What can barcoding do for fishery technologists?
9:30 Bennabou R.*, Zihler A., Desbiens M., Subirade M., Fliss I.
Listeria monocytogenes inhibition by bio-film produced from chitosan and divergicin M35
9:35 Lopez I., Pardo M.A.*,
A novel procedure for the identification of Anisakis simplex in seafood products by real time PCR
9:40 Mejlholm O.*, Dalgaard P.
Modeling and predicting the growth boundary of Listeria monocytogenes in lightly preserved seafood
18
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
10:00Matamoros S.*, Pilet M.F., Prévost H., Leroi F.
Evaluation of psychrotrophic lactic acid bacteria as protective cultures for the biopreservation of seafood products
10:20Break
10:40Cadun A.*, Schubring R., Cakli S.
Comparison of the quality of fish fillets prepared onboard with and without high pressure treatment at both 50 and 100MPa prior to
freezing
11:00 Donovan C.*, Gill T., Allen D., Garduno R., Ku J., Quilliam M.
Identification and characterization of bacterial isolates capable of degrading paralytic shellfish toxins
11:20 Bogason S.*
The Chill-on integrated project
11:40 Marques A.*, Encarnação S., Pedro S., Nunes M.L.
Antibacterial properties of garlic oil, oregano oil and chitosans to Salmonella enteritidis cultured at different temperatures
12:00 Lunch and Student Awards Presentation - room Place Montcalm
Sponsored by UQAR, INAF, ABK Gaspésie inc. and Oceanova Biotechnologies inc.
Wednesday, November 1st – room Lemieux
PM
New concepts to minimize seafood associated risks (continuation)
Sponsored by Fisheries and Oceans Canada/Pêches et Océans Canada
14:00Silva H.*, Palma M.
Enteric viruses in bivalve molluscs from portuguese production areas
14:20Lee J.L., Levin R.*
Quantification of total viable bacteria on fish fillets by using the Polymerase Chain Reaction
14:40Tita G.*, Saint-Louis R., Pelletier É.
Seafood-processing: a key strategy to reduce cadmium and arsenic related health risks in sea scallop (Placopecten magellanicus)
consumption
15:00Pedro S.*, Oliveira, A.C.M., Nunes, M.L., Bernardo, F.
Enumeration of Staphylococcus spp. and S. aureus in salted seafood by using a direct viable count fluorescent in situ hybridisation
protocol
15:20Saint-Louis R.*, Tita G., Pelletier É.
Arsenic speciation in seafood: algae, sea urchin and molluscs.
15:40Bogason S.*, Yngvadóttir E.
Quality of life - integrated benefit and risk analysis. Web-based tool for assessing food safety and health benefits
16:00Joint Closing Address
Thursday, November 2nd
9:00 Visit to Grizzly Smokehouse/Fumoir Grizzly
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
19
Advances in Processes and
Added Value of Products
Oral presentations
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
21
Advances in processes and added value of products
Keynote lecture
Stabilization and Formulation of Shelf-Stable Healthy
Food Ingredients Fortified with Omega-3 Oils from Fish
Barrow C.J.,* Jin Y., Curtis J., Cloutier S.
Ocean Nutrition Canada
N
umerous clinical trials, population studies and animal experiments have demonstrated the beneficial effects of EPA and
DHA from fish oil for cardiovascular disease, brain and retinal development, and inflammatory mediated diseases such
as Alzheimer’s disease and depression. Several international groups such as ISSFAL, the AHA, Australian NHMRC and the
British Nutrition Foundation have provided recommendations for the daily intake of EPA and DHA. Despite these recommendations, consumption is low and a nutritional gap exists in many countries. Fortification of foods with fish oil aims to reduce this
nutritional gap. However, adding EPA and DHA to foods requires a stabilization technology that enables the sensory shelf life
of the food to remain unchanged. Methods such as spray-dried emulsions, fluidized bed coating, liquid emulsions, liposome
entrapment and complex coacervation have been used to stabilized oils rich in EPA and DHA for delivery into foods. Complex
coacervation is one of the most commercially successful of these methods and is used by Ocean Nutrition Canada. After microencapsulation, fish oil can be formulated into food products such as bread, yogurt and orange juice so that no fishy flavor
is observed for the shelf life of the food product. This presentation will described the process of complex coacervation and
describe examples of food formulation that has led to the launch of several food products containing fish oils, in Canada and
worldwide.
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
23
Advances in processes and added value of products
Optimization of the production of antioxidant peptides
from saithe (Pollachius virens) hydrolysate
Chabeaud A.1,2*, Dutournie P.2, Guérard F.1, Vandanjon L.2, Bourseau P.2
1. ANTIOX Laboratory Université de Bretagne Occidentale Quimper, France
2. LET2E Laboratory EA3373 Université de Bretagne Sud Lorient, France
P
roduction of fish protein hydrolysates by proteinase treatment is a means to transform by-products into new products with
improved functional and biological properties. In recent years, a large number of hydrolysates exhibiting hormonal, growth
stimulatory, immuno-modulatory functions, anti-hypertensive and antioxidant effects have been generated from fishery byproducts.
We are currently investigating the production of a saithe hydrolysate having antioxidant and DPPH° radical scavenging properties by a two-step process including enzymatic hydrolysis and membrane separation. This work includes: i) optimization of
the enzymatic hydrolysis ; ii) fractionation of the hydrolysate by chromatographic techniques to identify the physicochemical
properties of bioactive peptide classes ; iii) concentration and refining (desalting and/or fractionation) of the hydrolysate by
membrane processes according to these chromatographic analyses.
This paper focuses on the optimization of enzymatic hydrolysis parameters using response surface methodology (point i) and
on the scaling up of the hydrolysis process.
Enzymatic hydrolysis of saithe (Pollachius virens) proteins by Alcalase® 2.4L was investigated in a 1L-batch reactor. The
combined effects of pH, temperature (T), enzyme/substrate ratio (E/S), and time (t) on antioxidant and DPPH° radical scavenging effects were described through Response Surface Analysis (RSA). The obtained model showed good concordance with
experimental data. At the following critical values: pH = 8, T = 60 °C, E/S = 2.3%, time = 10.8 min, the antioxidant (β-carotene
test) and DPPH° radical scavenging capacity of the hydrolysate reached 69.8% and 17.4%, respectively, while the degree of
hydrolysis (DH) did not exceed 10.96%. No relation between DH and antioxidant properties has been observed.
The enzymatic hydrolysis of saithe proteins has also been carried out in optimum conditions in a 20L-batch reactor. After the
scaling up of the process, the antioxidant and scavenging properties of the hydrolysate at 10.8 min amounted to 74.5% and
15.0%, respectively.
Future works will concern physicochemical characterization of the active peptides by chromatographic analyses (size exclusion, ion-exchange, reverse phase) and fractionation of the hydrolysate using membrane processes (nano- and ultrafiltration)
with the aim to improve the specific activity of the hydrolysate.
This investigation was supported by Région Bretagne, France (PRIR, «Activemb») and by the IP 6th FP European Program
SEAFOODplus.
24
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
Advances in processes and added value of products
Solid phase micro extraction as a tool to isolate
lipid classes and deterioration of marine lipids
Dybvik A. I., Rustad T., Falch E.*
1. SINTEF Fisheries and Aquaculture, Trondheim, Norway NO-7465
2. Dep. Biotechnology, Norwegian University of Science and Technology, Trondheim, Norway NO-7000
T
he interest in using marine ingredients in functional food systems is increasing due to the increased evidence of health
benefits especially from the long chain omega-3 fatty acids. Most medical studies on the health benefits of marine omega-3
fatty acid have been investigated using commercial fish oils or concentrates. In commercial fish oils, the fatty acids are esterified in triacylglycerols. Seafood also contains phospholipids that are important molecules comprising omega-3 fatty acids.
There is a growing interest in these components both in the healthcare and food industry.
In this work we have optimized a solvent system for separating lipid classes (including individual phospholipids) and reaction
products from lipid deterioration caused by enzymatic and oxidative processes. The main aim of these studies was to increase
the knowledge on the different lipid constituents by extracting the different classes and thereby allow for detailed characterisation of the lipids.
A solid-phase extraction (SPE) method, using silica bonded aminopropyl columns, was used to separate triacylglycerols,
cholesterol, phospholipids, steryl ester, and hydrolysed acylglycerols. The lipid classes were analysed by thin layer chromatography (TLC-FID) and more advanced analytical techniques such as Nuclear Magnetic Resonance (NMR) Spectroscopy
and Liquid Chromatography Mass Spectroscopy. NMR spectroscopy was found unique for providing information on the acyl
regiospecific position of the fatty acids in the different lipid classes.
The raw material used, were lipids extracted from muscle and gonads (roe and milt) from cod (Gadus morhua). Most lipid
classes were obtained with high purity and the solvent extraction system enabled separation of phosphatidylcholine and phosphatidyletanolamine with 95% and 100% purity respectively.
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
25
Advances in processes and added value of products
Mild procedure for obtaining lipidic and peptidic
fractions from sardine (Sardina pilchardus) heads
Dumay J.1*, Barnathan G.2, Jaouen P.3, Bergé J. P.1
1. IFREMER, Département STAM, rue de l’ile dYeu - BP 21105, F44311, Nantes Cedex 3, France
2. Université de Nantes Atlantique, Universités SMAB EA 2160 2, rue de La Houssinière, BP 92208 F44322. Nantes Cedex 3, France
3. GEPEA, Université de Nantes - UMR CNRS 6144 119, boulevard de l’Université, BP 420 F44606. Saint-Nazaire Cedex, France
A
ccording to the recent Food and Agriculture Organization (FAO) report on bycatch and discards, the weighted discard is
estimated at 8%, and the yearly average discards are estimated to be 7.3 million tons1. Worldwide, total landings of small
pelagics (sardine, mackerel and horse mackerel) are about 4 million tons leading to about 50,000 tons of discards. Nowadays,
by-products are mainly transformed but 96% of those processes consist in low-value production (fish meal and oil, pet food..).
Lots of papers have reported health benefits of fish consumption. Fish by-products have the same biochemical composition
and potentially the same benefits, notably concerning proteic and lipidic fractions. However, it is actually quiet difficult to obtain
those two fractions using the same sustainable process without any denaturation of one of them.
The objective of this study is to propose a mild process that can lead to obtain both fractions (lipids and peptides). Thus, sardine (Sardina pilchardus) heads were hydrolysed with an industrial protease (Protamex, Novozymes AS, Denmark). Hydrolysis
had been optimized by experimental design procedures in order to provide the highest lipid recovery. After centrifugation and
collection of oily phase, the soluble part had been filtered through an ultrafiltration membrane (PES, Pall, USA). With such
process the lipids contained in the soluble fraction were totally concentrated in the retentate while the peptides were collected
in the filtrate fraction.
Experimental designs has allowed, with tendency of 75%, to conduct an hydrolysis with optimal hydrolysis duration, temperature and enzyme concentration in order to obtain the higher lipid release (contained in the oily and the soluble part). Around
60% of the lipids have been recovered in the oily phase after the hydrolysis step while 17% of the total lipids have been localised in the soluble part. Those lipids were mainly polar lipids (eg. phospholipids). Lipids obtained in all the fractions were rich in
w3 fatty acids (around 25% of total fatty acids), especially in EPA (12%) and DHA (9%). The peptides obtained had molecular
weight below 10 KD.
This study has proven that sustainable procedures can lead to the production of interesting fractions from fish by-products.
These fractions could find applications in food or feed, or in more valuable areas such as nutraceutic or pharmaceutical
fields.
This work was performed using the SiobioCle LIMS (Chatou, France). Authors also want to thanks to the Euro Seafood Trading
Company (France) for providing PhD grant for this research. This work was performed within the Integrated Research Project
SEAFOOD plus, contract No FOOD-CT-2004-506359. The partial financing of the work by the European Union is gratefully
acknowledged.
1. Kelleher, K. Discards in the world’s marine fisheries: an update. FAO fischeries technical paper, 2005, 470
26
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
Advances in processes and added value of products
Application of chitosan and its phosphate derivatives for quality
preservation of fish stored at refrigerator temperature
Cakli S., Kisla D., Ataman C. A., Dincer T.*, Kelesoglu S.1, Cadun A., Kes M.1
1. Ege University, Faculty of Fisheries, Department of Fishery and Fish Processing Technology, 35100 Bornova, Izmir, Turkey
Izmir Institute of Technology Urla TR 35430 Izmir, Turkey
T
he objective of this study was to characterize chitosan and its phosphate derivatives prepared from pink shrimp (Parapenaeus longirostris) shell wastes and to determine the effects of these biopolymers on shelf-life extension of selected fish
type. Chitosans with a medium degree of deacetylation, high degree of deacetylation and their phosphate derivatives were
used.
For determining the shelf-life whole gutted Dicentrarchus labrax were dipped into 1% concentrations of chitosan and chitosan
phosphate derivatives solutions, were analyzed.
Methodology
Preparation of chitosan with different degree of deacetylation
Chitin was isolated from pink shrimp shell wastes by sequential treatments with 2.5 NaOH and 2 N HCl. This chemically treated
chitin was deacytelated with 40% NaOH at 100 oC for 2.5 hours to obtain chitosan (medium degree of deacetylation). High
degree of deacetylation chitosan was obtained by the deacetylation with 50% NaOH at 140 oC in an oil bath for 3 hours.
Preparation of phosphate derivatives (nanoparticles) of chitosan
To obtain phosphate derivatives (nanoparticles) of chitosans first chitosan dissolved at 0.5% (w/v) with 1% (v/v) acetic acid
and then raised to pH 4.6-4.8 with 10N NaOH. Phosphate derivatives (nanoparticles) of chitosan formed spontaneously upon
addition of 1ml of an aqueous tripolyphosphate solution (0.25%, w/v) to 3ml of chitosan solution under magnetic stirring. Nanoparticles were purified by centrifugation at 9000g for 30 min. Supernatants were discarded, and the chitosan nanoparticles
were extensively rinsed with distilled water to remove any sodium hydroxide and then freeze-dried to use in the experiment.
Characterization of chitosan and Its phosphate derivatives (nanoparticles)
Chitosan and phosphate derivatives (nanoparticles) have been characterized with FT-IR (Fourier Transform Infrared Spectroscopy, SEM (Scanning Electron Microscopy), XRD (X-Ray Diffraction Analysis), viscometry, elemental analysis and colloidal
titration.
Chemical Quality Analysis
Trimethylamine (TMA) analysis was carried out according to the method proposed by (AOAC, 1984). Total volatile basic nitrogen (TVB-N) was determined according to the method of Vyncke (1996). Thiobarbituric acid (TBA) was determined according
to the method proposed by Tarladgis et al. (1960). The pH value was recorded using a pH meter (HANNA model Microprocessor). Color measurement was carried out with Dr Lange model spectro pen using method of Schubring (2002). Texture analysis, TPA and WHC were performed by using TAXT plus texture analyzer.
Microbiological Analysis
Psychrotrophic bacteria and coliform bacteria counts (Tsai et al., 2002) were determined in the samples.
Results
In selected fish specie shelf life differences were determined according to the analysis results . Different chitosan treatments
with a medium degree of deacetylation, high degree of deacetylation and their phosphate derivatives were affected the shelf
life of each batches.
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
27
Advances in processes and added value of products
Impacts of protein dispersion
on fish muscle protein gelation
Wright B.J., Pope W.W., Johnston D.A., Lanier T.C.*
Department of Food Science, Box 7624, North Carolina State University, Raleigh, North Carolina, USA 27695
G
els made from meat protein isolates produced by alkaline pH shifting are generally stronger and more deformable when
compared to gels prepared similarly from lean meat or surimi (water-washed meat). We hypothesized that pH shifting causes more disruption of the myofibrillar structure, allowing for greater dispersion of the proteins and thus stronger gel formation.
To evaluate effects of ultrastructural disruption and dispersion independent of pH shifting, fish myofibrils were treated with isolated calpain to disrupt Z discs and thereby possibly effect a similar level of myofibrillar dispersion as does alkaline pH shifting
(adjust meat slurry to pH 11 followed by isoelectric precipitation at pH 5.5). TEM was used to observe changes in ultrastructure
in gels produced by subsequent addition of NaCl and heating. A trained panel (n = 10) evaluated the disruption and dispersion
observable in micrographs. Torsion testing was used to evaluate gel fracture properties. Fracture stress and strain values for
the calpain treated samples were not significantly different than for the pH shifted samples, and these were greater than for
mince or surimi. Panel evaluation of TEM micrographs supported this order of gelation, showing greater disruption/dispersion
of myofibrillar microstructure associated with stronger, more deformable gels.
28
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
Advances in processes and added value of products
Electro-separation of chitosan oligomers by electrodialysis
with ultrafiltration membrane (EDUF)
Aider M.*1, Arul J.1, Brunet S.2, Bazinet L.1
1. Institute of Nutraceuticals and Functional Foods (INAF) and Department of Food Sciences and Nutrition, Pavillon Paul Comtois, Université
Laval Québec (Qc) Canada G1K 7P4
2. ISM Biopolymer Inc. 220, Denison E., Granby (Qc) Canada J2H 2R6
C
hitosan oligomers are widely used in biotechnology, pharmaceutical and health food industry because of their bioactivity.
It has been demonstrated that their main physiological activities, nutraceutical and functional properties depend on their
molecular weight. Two main methods are usually used in the industry for chitosan oligomers production: acid and enzymatic
hydrolysis. Acid hydrolysis produces a large amount of short-chain oligosaccharides, varying mainly from monomer to trimer.
Enzymatic hydrolysis of chitosan produces chitosan oligosaccharides ranging from dimer to octamer. Furthermore, the final
product for both methods is a mixture of molecules of different molecular weights and contains minerals. The aim of the present
study was to evaluate the effectiveness of an electrodialysis- ultrafiltration process for separation and purification of chitosan
oligomers. Effects of molecular weight cut-off of the ultrafiltration membranes stacked in an electrodialysis cell, chitosan oligomer chain length, pH of the medium on the electro-separation were studied.
A mixture of chitosan oligomer (dimer, trimer and tetramer) was treated. Five cellulose ester ultrafiltration membranes of different molecular weightcut-offs (500, 1000, 5000, 10000 and 20000 Da) from Spectrum Laboratorie, Inc (Rancho Dominguez,
CA, USA) were tested. A MicroFlow type electrodialysis cell (ElectroCell AB, Täby, Sweden) with an effective area of 10 cm2
was used.
The membrane MWCO, pH, cell configuration, oligomer chain length and processing time were significant factors on the
electro-migration rate of the oligomers through ultrafiltration membranes. Contrary to the 20000 Da MWCO UF-membrane
which was permeable to all chitosan oligomer, the 500 Da MWCO UF membrane did not exhibit any permeability. The 1000,
5000 and 10000 Da MWCO UF-membranes showed different selectivities to the chitosan oligomers, depending on process
conditions . The 1000 Da membrane was impermeable to the tetramer during 3 hours of operation, whereas 5000 and 10000
Da membranes were impermeable to the tetramer during the first 2 hours of the treatment, but they both showed similar
selectivities. Electro-migration rates of the chitosan oligomers varied between 1.05 and 14.45% depending on the operating
conditions (membrane MWCO and processing time). Chitosan oligomer electro-migration rates decreased by increasing pH of
the medium. The dimer showed the highest electro-migration rate at all pH values, followed by the trimer and tetramer. It was
shown that it was possible to separate the dimer and trimer from the mixture at pH 6 or the dimer from the mixture at pH 7 or
according to the processing time.
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
29
Advances in processes and added value of products
Production and characterization of alkali extracted
protein powders from pollock and salmon heads
Bechtel P. J.1*, Sathivel S.2, Oliveira A.C.M.2
1. USDA-ARS Subarctic Agricultural Research Unit, University of Alaska Fairbanks, 245 O’Neill Bldg., Fairbanks, Alaska, USA 99775-7220
2. Fishery Industrial Technology Center, University of Alaska Fairbanks, School of Fisheries & Ocean Sciences, 118 Trident Way Kodiak,
Alaska, USA 99615-7401.
T
he Alaska pollock (Theragra chalcogramma) harvest was over 1.4 million T in 2005 that yielded over 240,000 T of heads.
Pollock heads are low in fat (2%) and have approximately 15% protein. The 2005 harvest of wild salmon (Oncorhynchus
spp.) from Alaska waters was over 400,000 T, which yielded approximately 65,000 T of heads. Much of the lipid in salmon is
in the head and pink salmon heads have approximately 11% fat and 14% protein. There are large amounts of myofibrillar and
connective tissue protein in fish heads that could be extracted and used protein ingredients.
The objective of this study was to produce protein powders from pollock heads (PH) and red salmon heads (SH) using alkali
extraction procedures and characterize protein and lipid constituents of both soluble and insoluble powders. Although alkali
extraction procedures have been used to make high quality gels, our goal was to use this methodology to produce protein
powders from by-products.
Both red salmon and pollock heads were collected from fully automated commercial processing lines and stored at -20 oC until
extraction. Triplicate aliquots of minced heads were homogenized in 9 volumes of water, proteins solubilized at pH 11, insoluble
protein (IP) removed after centrifugation and soluble protein (SP) then precipitated at pH 5.5 and collected by centrifugation.
SP and IP fractions were freeze dried. Yields were determined and samples analyzed for proximate composition, mineral and
amino acid and fatty acid contents, lipid classes, nitrogen solubility, emulsion stability and fat adsorption properties, SDS-PAGE
electrophoresis, and TBA values.
Pollock head SP had protein, fat and ash contents of 66%, 27% and 2%, respectively; and IP had protein, fat and ash content
of 62%, 13% and 19%, respectively. Salmon head SP had protein, fat and ash content of 80%, 14% and 2%, respectively; and
IP had protein, fat and ash content of 51%, 25% and 18%, respectively. Amino acid analysis indicated IP fractions from both SH
and PH had higher% proline and lower amounts of some essential amino acids when compared to SP fractions. IP fractions
contained high levels of calcium (~4.6%) and phosphate (~2.4%). Protein powders from PH had higher color L* values than
comparable SH powders and IP powders were lighter in color than SP powders. Pollock head SP had higher fat adsorption
capacity (5.6 mL of oil/g protein) than IP. Differences in SDS gel electrophoresis band patterns were observed. Lipid classes of
both SH fractions indicated 89-95% triacylglycerides (TAG) and 1-4% free fatty acids (FFA) and 2.4-2.6% phospholipids (PL).
Pollock head IP fraction was 83% TAG, and 5.4% PL; however the SP fraction had very high levels of FFA. The % omega-3
in both pollock head fraction was approximately 20% and in salmon head fractions 23%. Percent lipid classes were similar for
both SP and IP factions.
The soluble protein (SP) powders extracted from pollock and salmon heads have potential as functional protein ingredients.
Insoluble isolates (IP) from pollock and red salmon heads have potential applications as feed and food ingredients.
30
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
Advances in processes and added value of products
Study of gel strength improvement of alkaline
processed surimi of blue whiting
Nolsøe H.
Faroese Fisheries Laboratory, P.O. Box 3051, Nóatún 1, FO-110, Tórshavn, Faroe Islands
Objective
To compare the gel properties of surimi produced from blue whiting in a traditional industrial process, as performed on board
a factory trawler, with surimi produced in a modified alkaline solubilization process as described by (Hultin H.O. and Kelleher
S.D., 2000), but in which the centrifugation process for separating the membrane lipids is replaced by a filtration process in
which un-dissolved material is removed by filtration through a double layer of cheese cloth, a row of tests were performed
comparing different samples of surimi from blue whiting fillets (Micromesistius poutassou) into which different additives for
improvement of the gel quality were let.
Methodology
Industrially processed surimi was compared to laboratory processed surimi processed from fresh blue whiting. Gels were prepared according to industrial standard procedures. Testing of the gels was performed with a Rheo Tex model AP - 83 rheometer.
Gel improving additives were used in investigation of the gel improving abilities.
Results
The results show that there is a substantial difference of the gel quality of industrially processed surimi and surimi processed in
a modified alkaline process. The tests of the gel improving additives show that it ispossible to improve the gel quality substantially by using gel improving additives.
Conclusion
In further investigations the differences in yield and gel quality should be investigated for blue whiting surimi processed in a
traditional way compared to acid/alkaline surimi processed with and without centrifugation. The tests should be performed with
the same raw material making the results comparable.
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
31
Advances in processes and added value of products
Protein powders from fish processing by-products
Plante S.*1, Oliveira A.C.M.1, Sreenivasan A.1, Smiley S.1, Bechtel P.J.2
1. Fishery Industrial Technology Center, University of Alaska Fairbanks, School of Fisheries & Ocean Sciences, Kodiak, Alaska, USA
2. United States Department of Agriculture/Agricultural Research Service Subarctic Agriculture Research Unit, University of Alaska Fairbanks
School of Fisheries & Ocean Sciences, Fairbanks, Alaska, USA
D
uring the last decade, more than 2 millions metric tons (mt) of fish were harvested each year in Alaska, with walleye
pollock (Theragra chalcogramma) being the most abundant fish species at more than 1 million mt harvested annually.
Assuming that 25% of the fish biomass is used for human food, a considerable amount of by-products is available to process
into fishmeal, solubles (concentrated stickwater) or bone meal. A detailed nutritional analysis of whitefish meat protein powder,
whitefish bone protein powder and whitefish concentrated stickwater protein powder could allow feed manufacturers to more
completely understand how varying concentrations of these ingredients would affect the nutritional efficiency of fish meals
made in Alaska. Some fishmeal producers add solubles back to their meals during the drying phase. Also, because fishmeal is
made from byproducts, a fraction of the bone in the final product is often removed to reduce the ash content. Bone meal made
in Alaska contains as much as 30-40% protein. However, much of the protein is collagen. This complicates the calculations for
feed manufacturers in estimating the nutritional efficiency of the particular fishmeal in their feed formulations. To help resolve
these nutritional uncertainties, we produced powders from whitefish fillet, whitefish solubles, and purified whitefish bone for
nutritional analysis. Frozen pollock fillets were purchased at a local seafood processor. Fillet were thawed ~36 hours in a coldroom before drying in an air-forced oven at 60 °C for ~19 hours. Solubles were collected at a local fishmeal company and dried
with a drum dryer (Buflovak 15 cm × 20 cm Atmospheric Double Drum Dryer). Steam pressure in the drums was ~80 PSI. The
drums rotated at 1.5 RPM with a 0.15 mm clearance. Clean whitefish bones were collected at a local fishmeal company. Fish
bone were finely grounded and then heated to ~80 °C for 25 minutes to separate the proteins from the minerals. The « bone
protein » fraction was then dried in a Littleford vacuum dryer (Model FM 130-0) for about 5 hours. All final products were dried,
milled to a fine powder, vacuum-packed and stored at -20 °C until analyzed or forwarded to our scientific partners for nutritional
testing. Protein contents (dry weight basis) in the fillet, solubles and bone fraction powders were respectively 90%, 65%, and
61%. Dried solubles were high in lipids (25%) compared to fillet (4%) or the bone fraction (7%). Ash content was high in the
bone fraction (32%), but was lower than raw fish bone (62%). As expected, ash content were the lowest in fillet (6%) followed
by the dried solubles (11%). We also present the results of amino acids, mineral, lipid classes and fatty acid analyses that were
performed on each dried product.
32
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
Advances in processes and added value of products
Functional and biochemical characterization of proteins
remaining in solution after isoelectric precipitation
Pires C., Batista I., Godinho V., Nunes M.L.*
INIAP-IPIMAR, Av. Brasília 1449-006 Lisbon, Portugal
A
cid and alkaline-aided processes have been used to produce functional protein isolates. These processes are based on
the solubilisation of muscle proteins at low and high pH followed by precipitation of soluble proteins at pH 5.5. The resulting
supernatant from this precipitation presents nitrogenous compounds including soluble proteins. These proteins could be recovered and may represent an additional value for the global process of upgrading Cape hake by-products. Thus, it was objective
of this work to recover and characterise the proteins present in the supernatant resulting from isoelectric precipitation.
“Sawdust” from Cape hake portioning was used as raw material which was alkaline solubilised and the main protein fraction
recovered by isoelectric precipitation. The collected supernatant was concentrated by ultrafiltration (MWCO 30 kDa) and spray
dried.
The protein profile of the supernatant, filtrate and retentate was analysed by gel filtration chromatography and SDS- PAGE
electrophoresis. The proteins in the supernatant had molecular weights lower than 73 kDa, in the retentate the main proteins
had about 18 kDa and 73 kDa and some proteins with 59 kDa were detected in the filtrate.
The protein and ash content of dried proteins was 74.0% and 9.1%, respectively. The color parameters of protein powder
was L* = 86.26, a* = -0.06 e b* = 5.47. In what concerns the biochemical characterisation of these proteins the results of the
hydrophobicity, total and reactive sulphydryl content were 6547, 6.81x10-5 mol/g of protein and 2.46x10-5 mol/g of protein, respectively.
The foaming capacity and the foaming stability after 1 hour of these proteins were 29.4 ml of foam/g of protein and 86.3%,
respectively and the emulsifying capacity was 38.4 g of oil/g of protein.
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
33
Advances in processes and added value of products
Keynote lecture
Processing, adding value, and quality of aquatic foods
Balaban, M.
University of Florida
P
rocessing, adding value, and quality of aquatic foods: Aquatic foods constitute an important and valuable source of food
and raw materials. Processing to assure safety and to extend shelf life, as well as to add value is necessary and desirable.
Heating is an important process. It can be optimized to assure safety and preserve quality. An example from optimization of
shrimp cooking will be given, with emphasis to improve tenderness and yield.
Other potential technologies will be briefly mentioned, with their strengths and areas to be improved.
With the internationalization of trade, standardization of quality evaluation is becoming critically important. Automation and
more objective measurement of quality is desirable. Examples will be given in the measurement of visual attributes using machine vision, as well as simplifying the determination of smell related attributes using electronic sensors. Extrapolation to future
possibilities will be attempted.
34
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
Advances in processes and added value of products
FT-IR microspectroscopy: investigation of changes in
microstructure and muscle proteins due to salting in
Atlantic salmon of different raw quality
Böcker U.1,2*, Aursand I.3, Veliyulin E.3, Kohler A.1, Ofstad R.1
1. Matforsk AS Norwegian Food Research Institute, Norway
2. Department of Chemistry Biotechnology and Food Science, Norwegian University of Life Sciences, Norway
3. Sintef Fisheries and Aquaculture, AS, Norway
M
uscle proteins are of major importance for quality of muscle foods like fish, and they are greatly influenced by different
processing methods like freezing, heating or salting and by the raw quality prior to processing.
Fourier Transform Infrared (FT-IR) microspectroscopy has become a valuable analytical tool for examining the chemical composition of biological cells and tissues on a microscopic scale.
The scope of this study was to investigate effects of low concentrations of salt on muscle protein structure and microstructure of
Atlantic salmon by combining light microscopy and FT-IR microspectroscopy. The effect of salting was investigated with respect
to differences in the raw quality of the fish before salting.
Fillets of pre-rigor, post-rigor and frozen-thawed fish were salted in 16% NaCl-brine for 4 hours followed by 10 hours of distribution time. Samples taken before and after salting were investigated by light microscopy and FT-IR microspectroscopy. The
acquired FT-IR spectra were compared by using multivariate data analysis.
The light microscopic images showed distinct structural differences in the muscles of the three raw qualities, which at the
same time showed differences in their water distribution profiles. The different raw quality influenced salt diffusion and final salt
content resulting in a higher salt content in frozen/thawed than in pre-rigor and post-rigor fish. After salting the frozen/thawed
fish showed most swelling compared to the other two qualities. There were major differences in the FT-IR spectra - especially in
the protein region of the spectra - prior to salting which were due to the variation in the raw quality of the fish. Salting introduced
further spectral differences in the protein-related bands with the largest effect found for frozen/thawed fish, which possessed
the highest salt content of the three qualities.
The results indicate that both raw material and salt content give rise to differences not only in the muscle microstructure, but
also cause differences in the FT-IR microspectroscopic fingerprint of muscle proteins. FT-IR microspectroscopy can serve as
a useful tool in investigating effects of processing on fish muscle.
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
35
Advances in processes and added value of products
The effect of high hydrostatic pressure on the microbiological, physical,
and sensory quality of fresh blue crab (Callinectes sapidus) meat
Suklim K., Flick G.*
Food Science and Technology Department, Virginia Tech (0418), Blacksburg, Virginia, USA 24061
V
acuum-packaged fresh lump blue crab meat (Callinectes sapidus) was pressurized at 300 and 550 MPa for 5 min at 25 ºC
and evaluated for changes in microbiological, physical, and sensory qualities after pressure treatments and during storage
(4 ºC for 31 days). A pressure of 300 MPa caused a 1 log reduction in total aerobic plate count and a 3 day lag period, whereas
550 MPa inactivated 2 logs in total aerobic plate count with no evident lag phase. Physical and sensory qualities of pressurized
crab meat were not statistically different from the untreated crab meat (P>0.05). High hydrostatic pressure treatments killed or
inactivated pressure-sensitive microflora in the fresh crab meat resulting in the following surviving microorganisms: Aerococcus
viridans, Brevibacillus agri, Brevibacterium iodinum, Brevibacterium linens, Brevibacterium casei, Brevibacterium epidermidis,
Enterococcus mundtii, Enterococcus avium, Enterococcus solitarius, and Macrococcus (Staphylococcus) caseolyticus. Under
reduced oxygen and low temperature storage conditions, sensory evaluations along with the identification of predominant
organisms in fresh and pressurized crab meat (550 MPa) were conducted to determine shelf-life as well as to identify dominant spoilage microorganisms. A pressure of 300 MPa extended shelf-life of fresh crab meat from 17 to over 24 days with
the prevalence of Carnobacterium piscicola. Crab meat treated with 550 MPa was not rejected by sensory panels at day 31;
Enterococcus spp. was identified as the predominant microorganism suggesting that this organism could have an inhibitory
effect to the other microflora.
36
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
Advances in processes and added value of products
Correlations between protein oxidation and texture during
ripening of old fashion marinated herrings
Andersen E.1, Christensen L.2, Christensen M.2, Baron C.P.1*
1. Danish Institute for Fisheries Research, Dept. of Seafood Research DTU, Building 221 Kgs. Lyngby, Denmark, DK-2800
2. The Royal Veterinary and Agricultural University, Dept. of Food Science, Rolighedsvej 30, Frederiksberg C,, Denmark, DK-1958
H
errings are fatty fish, which are very susceptible to oxidation. During the production of old fashioned marinated herring,
herrings are stored for 6 months in brine, which contains a high level of salt and haemoglobin. Haemoglobin is known to
be a strong prooxidant in fish muscle but it is also believed to be able to induce protein cross-linking. Therefore its role in the
development of the characteristic texture of marinated herrings deserved further attention.
In this study the changes in texture during ripening of marinated herring was investigated mechanically after optimization of the
Warner-Bratzler shear test (WB) and the texture profile analyzer (TPA). In addition, the impact of hemoglobin on texture was
further examined by investigating changes at the muscle protein level by investigating protein oxidation, protein degradation
and protein cross-linking.
Fresh herring as well as herring marinated for 2, 85, 151 and 371 days under normal conditions or under condition where
extra blood brine was added during the processing were filleted and sampled for mechanical testing. SDS-PAGE (on muscle
homogenate) was performed on all samples. In addition western blotting against actin, myosin, and protein carbonyls were
also performed.
The texture profile analyzer was able to measure the difference in texture in marinated herrings during ripening and detected
changes in hardness of the fish muscle. An increase after 2 days ripening and a significant decrease in the hardness of the fish
muscle was observed after 371 days. The WB was also able to confirm these results but extraction of the information from the
obtained data was more difficult/time consuming. The SDS-PAGE revealed extensive degradation of the fish muscle proteins
during ripening with degradation of myosin being very pronounced already after 85 days. Protein carbonyls indicated that the
high molecular weight proteins were preferentially oxidized and western blotting of myosin revealed some cross-linking after
2 days of ripening. Based on our obtained data we postulate the oxidative reactions inducing protein degradation and crosslinking is responsible for the characteristic texture of marinated herring. It is yet to be confirmed that hemoglobin is the main
actor in these oxidative reactions.
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
37
Advances in processes and added value of products
High processing of seafood for shelf-life extension,
assuring safety and improve quality
Ramaswamy H. S.
Department of Food Science, McGill University, Macdonald Campus, Ste Anne de Bellevue (QC) Canada H9X 3V9
H
igh pressure processing (HPP) is gaining tremendous popularity for both short term (extended shelf-life, ESL) and long
term (shelf-stable) processing of foods. In both of them, destruction of pathogenic bacteria are of primary concern. In
general the pressure processing requirements are quite different for the two applications. This presentation will highlight the
application of HPP to seafood processing, both for the mild ESL type application involving inactivation of common pathogens in
refrigerated seafood such as Listeria monocytogenes or Escheria coli O157:H7 or for shelf-stable high temperature application
where spore destructions become mandatory. Safety aspects in terms of challenge studies and HPP aspects related to product
quality will be addressed using case studies.
Ultra high pressure (UHP) is a non-thermal processing method that generally not affects the nutritional and sensory qualities
of food. It is an alternate procedure for food processing that has gained popularity in recent years because it has tremendous
advantages over conventional thermal processing. However, commercialization of high pressure processing technology has
not been achieved completely because there is still need for continued research to demonstrate the safety of the process.
The process currently being considered as novel, it cannot rely on information from traditional technologies. Studies related to
inactivation of microbial pathogens and spores of high pressure resistance therefore are of high priority for the success of the
process. HP research has been extensively carried at McGill University for the past 10 years and has been well supported by
grants from NSERC and MAPAQ.
38
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
Advances in processes and added value of products
Fish fillet inspection - quality control by imaging spectroscopy
Nilsen H.*, Agnar K.H., Sivertsen H.
Fiskeriforskning, Muninbakken 9-13 9291, Tromsø, Norway
I
ndustrial processing of fish for human consumption has more and more become the task of high speed and accurate machinery; developed especially for fragile products such as fish. Gutting and heading, filleting and skinning is all made at high
speed and high precision. Certain tasks however have been more complicated to implement at industrial pace, such as detection of parasites, blood speckles and other quality flaws.
The objective of this work was to develop imaging spectroscopy as a tool for industrial quality evaluation of fish fillets. The
main focus has been on parasite detection; surface and embedded ones, as this is a matter that has long sought an industrial
solution. Other quality issues like blood spots, skin remnants as well as freshness have also been investigated.
Imaging spectroscopy, or also called hyperspectral imaging, is a way of identifying and recording the spectral and spatial characteristics of an object simultaneously. Every single point of an object is recorded with its spectral features. As this obviously
gives rise to considerable amounts of data, both operational speed and processing speed must be high. The information is
analysed by multivariate methods as well as image processing tools.
Current results shows that in terms of parasite detection, imaging spectroscopy performs at the same level or better than trained operators in the fish processing industry. The method also differentiates between parasites and blood spots embedded
in the muscle. In addition it is possible to identify fillet irregularities such as skin remnants and colour defects. The spectral
measurements can also be applied for freshness assessment.
The method still needs to be improved to meet up with the requirements of speed and accuracy of the fish filleting industry. It
is believed that implementing this technology for the filleting industry will create new possibilities of product development and
product control, and in this way be beneficial both to the industry and the consumer.
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
39
Advances in processes and added value of products
Development and characterization of vacuum packaged wild pink
salmon (Oncorhynchus gorbuscha) jerkies using marinades
Oliveira, A.C.M.*, Crapo C.A., Himelbloom B.H., Morey A., Ambardekar A.
Fishery Industrial Technology Center, School of Fisheries and Ocean Sciences, University of Alaska Fairbanks, 118 Trident Way, Kodiak,
Alaska, USA 99615-7401
I
n 2005 Alaska pink salmon catch totaled about 420,000 T, of which 71% were pink salmon. The ex-vessel price for pink salmon was $0.12/lb, making it ideal for the manufacturing of value-added products such as jerky. Beef jerky is a very popular
product in the US and demand has been growing steadily for many years. Processors seeking new markets for salmon could
consider tapping the demand for jerkies by manufacturing one made from fish. Most salmon jerky is made from minced fish that
is extruded, smoked and dried. This product is nutritious but has rubbery texture that is often objectionable.
The most desirable jerky is made from whole muscle that retains the natural texture of fish. Traditionally this has been done
through a labor intensive process of hand slicing fresh fish fillets into very thin pieces. Our study developed a jerky made from
frozen pink salmon blocks that were band sawed into thin pieces eliminating the hand slicing process and decreasing production cost. Flavorings were added using marinade processes where frozen pieces were dipped in cold solutions. We tested
various marinades and determined their effect on shelf life proximate composition, fatty acids (FA), lipid classes, thiobarbituric
acid (TBA) values and water activity (aW) of salmon jerkies.
Fresh whole pink salmon was obtained from a seafood processor during summer 2005. Skinless, boneless fillets were handcut and frozen into blocks using a Dole plate freezer. Frozen salmon blocks were cut into strips (15 in. x 2 in. x 0.2 in.) using
a meat saw and dipped, for 20-30 sec on a marinade at the ratio of 2.5 kg salmon strips/kg marinade. Three marinades were
tested: 5% salt (S); 5% salt + 15% brown sugar (SS); 5% salt + 15% brown sugar + 2% commercial antioxidant (Kalsec; SSAO).
The strips were dried in a commercial smoker for 10.5 h at about 32 oC (± 2 oC). Samples were cooled to room temperature,
vacuum-packed, stored at 20 oC and 40 oC and analyzed at selected intervals up to 60 days.
Processing yields were about 26%, regardless of treatment. Jerky contained initially 72% protein, 18% moisture, 4% ash and
5% lipid with approximately 30% omega-3 FA (mainly EPA and DHA). Moisture loss in 60 days was 22% and 53-58% at 20 oC
and 40 oC, respectively. Addition of sugar maintained, for up to 30 days, aW values of 0.685 and 0.657 at 20 oC and 40 oC,
respectively. TBA values were low and did not exceed 2.7 micromol malondialdehyde/kg for all samples. Increase in FFA was
lower (38% and 59% respectively) in SSAO samples stored at 20 oC and 40 oC when compared to other samples stored at identical temperatures. The maximum aerobic plate count at 60 days was less than 8.0 x 103 CFU/g. Storage at 40 oC negatively
affected jerky quality, while sugar combined with storage at 20 oC were effective in maintaining the jerky quality for 60 days.
40
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
Advances in processes and added value of products
Effect of soluble gas stabilization and modified atmosphere
packaging on the quality of sardine fillets (Sardina pilchardus)
Pestana C.*, Gonçalves A., Mendes R.
Department of Technological Innovation and Upgrading of Fish Products, National Institute of Agrarian and Fisheries Research,
INIAP/IPIMAR
S
ardine (Sardina pilchardus) is a species that for its abundance assumes great importance in the Portuguese fishing sector,
representing about 50% of the annual total captures. However, in some periods of the year on account of its low fat content
a significant fraction of the captured sardine is not used for human consumption. In order to contribute for a better utilisation and
upgrading of this species the preparation of several products like fillets, mince and surimi has been assayed in recent years.
The aim of this study is to investigate the effect of the pre-treatment with soluble gas stabilisation - SGS (CO2 at 2 bar, 15 min
and 30 min) on the quality and shelf life of sardine fillets packed in three different conditions (air, vacuum (VP) and modified
atmosphere (MAP - 40% CO2: 5% O2: 55% N2)). During the storage at 2 ºC samples were regularly taken from all batches and
the quality changes evaluated by different methods, including chemical analysis (nucleotide degradation products, biogenic
amines, thiobarbituric acid reactive substances (TBARS), peroxide value and total volatile basic nitrogen (TVB-N)), microbiological analysis (total viable counts and anaerobic viable counts) and sensory evaluation.
Considering sensory criteria, the shelf life of SGS pre-treated sardine fillets was found to be 5 days in MAP, VP and air packaging. Results from bacteria counts showed that fillets without SGS treatment achieved a value of 7 log CFU/g in samples stored
in air, a value of 6 log CFU/g in samples stored in VP, and a value of 4 log CFU/g in samples stored in MAP. Fillets with SGS
treatment stored in air, VP and MAP, showed values between 3 and 4 log CFU/g, during 12 days of storage. The TVB-N content
remained almost constant, between 16 and 19 mg/100g muscle during the storage period for all samples. The formation of
TBARS increased with time for all storage conditions.
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
41
Advances in processes and added value of products
Processing optimization and determination of functional properties
of gelatin from King weakfish (Macrodon ancylodon) bones
Alfaro A., Prentice C.*
Laboratory of Food Technology Marine Products Processing Research Program, Department of Chemistry, FURG, University of Rio Grande,
P.O. Box 474 96201-900, Rio Grande, RS, Brazil
F
ish processing factories generate a great amount of byproducts. An important fraction of this waste consists of skin and
bonewith high collagen content. The whole utilization of these resources would increase industries profits and reduce environmental problems. Heat denaturation of collagen produces gelatin. Gelatin has numerous applications, particularly in the
pharmaceutical and food industries due to its properties of forming thermally reversible gels. There are two main kinds of gelatin with different functional properties: type A, obtained by acid treatment, and type B, obtained by alkali treatment. Bovine related diseases and religious restrictions to mammalian gelatin have lead to considerable interest in fish gelatin. This work aimed
to optimize, using factorial design and surface response methodology (SRM), alkali and acid treatment for gelatin obtainment
from King weakfish (Macrodon ancylodon) bones, based on gelatin functional properties. At acid treatment, independent variables were hydrochloric acid (HCl) concentration (2 and 4%), soaking time (36 and 72h) and extraction pH (2,0 and 4,0); gel
strength (g) was the dependent variable reaching mean values between 80 and 185g. HCl concentration and extraction pH had
significant ( p < 0,05) influence on processing, with optimal process conditions been obtained in a range of 2.0 to 2.3% and 2.4
and 2.0,respectively. Soaking time exhibited no significant effect on processing. Natural pH of gelatin is affected by extraction
pH, and is highly correlated with yield. Gelatins exhibited gelling and melting points of 16 and 23 ºC, respectively. Iminoacid
content was of 20.6% and molecular weight distribution was typical of type I collagen. In alkaline treatment, dependent variables were gel strength and gelatin yield. Independent variables were sodium hydroxide concentration (2 and 4%), soaking
time (48 and 72h) and extraction temperature (60 and 80%) and their respective central points. Gelatins exhibited gel strength
of 138-200g and 6.6-8.2% yield. Increases in extraction temperature carried out a significant (p<0,05) reduction in gelatin gel
strength. Soaking time (X2) and NaOH concentration (X3), also affected in a significant (p < 0,05) way gel strength, however,
the model was not statistically validate by variance analysis (ANOVA). Extraction temperature (X3), NaOH concentration (X1)
and their interaction had a pronounced effect on process yield, reaching higher values in the ranges of 74-80 ºC and 3.4%4.0%, respectively. High extraction temperatures lead to higher yields, but reduce gelatin gel strength. Gelatins gel strength is
largely dependent on molecular weight distribution, which in turn, is strongly affected by the extraction temperature. Functional
properties of gelatins from King weakfish bones, obtained by both process, make impossible their employ as a mammalian
gelatin substitute, but they can be used in other applications which require products with high melting point and intermediary
gel strength.
42
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
Advances in processes and added value of products
Gelatine degrading enzyme activities in herring (Clupea
harengus) and sardine (Sardina pilchardus) - the search
for causative enzymes of belly bursting
Felberg H.S.*1, Nunes M. L.2, Batista I.2, Martinez I.1
1. SINTEF Fisheries and Aquaculture, 7465, Trondheim, Norway
2. INIAP/IPIMAR, Instituto de Investigação das Pescas e do Mar, Avenidade Brasília,1449-006 Lisbon, Portugal
T
he term «belly bursting» describes the result of a rapid tissue degradation leading to post mortem disruption of the abdominal wall in some species of pelagic fish. The phenomenon occurs during the heavy feeding season, and sometimes the
degradation is so severe that a few hours post capture may be enough for the fish to become unsuitable for human consumption. Belly bursting has been associated with gastric acid leakage and pepsin activities in some species, and with tryptic and
chymotryptic activities in others. The gelatinolytic enzyme activities in the ventral muscle of some pelagic fish are currently
under investigation.
By using the technique of gelatine zymography it is possible to examine the gelatine degrading enzyme activities in fish tissues. Earlier it was shown that there are several gelatine degrading activities in extracts from ventral muscle of herring (Clupea
harengus) captured in the heavy feeding season in the spring that are not present in herring captured in the autumn. In this
presentation the progression of these gelatinolytic activities in spring herring during ice storage will be shown. Some results
of the testing of inhibitors on these activities in herring extracts and of the detection of gelatine degrading enzyme activities in
sardine (Sardina pilchardus) tissues will also be presented.
This presentation comprises part of the work aiming at finding enzymatic activities that may contribute to the belly bursting
phenomenon. Application of the results can help to develop storage conditions suitable for the inhibition of these activities thus
improving the on board preservation methods and increasing the quality and shelf life of the fish.
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
43
Advances in processes and added value of products
Evaluation of oxidative stability during
processing and storage of fatty fish mince
Eymard S.*, Baron C. P., Jacobsen C.
Danish Institute for Fisheries Research, Dept. of Seafood Research DTU, Building 221, Kgs. Lyngby, Denmark, DK-2800
T
he production of mince from fatty fish species such as horse mackerel has the potential to provide high nutritional value
products with appreciable level of n-3 fatty acids. However, due to their high content of polyunsaturated fatty acids, fatty
fish are very sensitive to lipid oxidation. Compounds formed by lipid oxidation have a deleterious effect on nutritional properties
and can also interact with proteins inducing significant change in physico-chemical properties of the products. The objective
of the study is to reveal oxidative reactions that take place in both lipid and protein fractions of fish mince, during processing
and storage of different horse mackerel mince products, but also to identify critical factors that can lead to deleterious quality
changes during storage.
Three horse mackerel mince products, were produced by mimicking the washing steps in the surimi production: 1) horse mackerel mince, 2) mince with intermediate fat content and 3) mince with a low fat content. These products were characterised
by qualitative and quantitative differences in their lipid (lipid content 2.4, 1.6 and 0.8% respectively) and protein fractions but
also by their initial level of lipid oxidation (peroxide values (PV) 2.8, 12.1 and 48.6 millieq peroxide/kg lipid respectively for
mince, intermediate mince and low fat mince). In order to evaluate oxidative degradation during storage, the three different
products were stored for up to 96 hours at +5 °C and for up to 6 weeks at -10 °C. Development of primary (PV) and secondary
(TBARS and volatile compounds analysis) lipid oxidation products were evaluated at regular intervals during storage. Protein
modifications were determined by measuring protein solubility, carbonyl groups and free thiol groups content. To determine the
impact of oxidative degradation on the sensory and physico-chemical properties of the products, sensory analysis and colour
measurement were also performed. Multivariate data analysis was performed to reveal interactions between the different parameters.
For both storage temperatures, lipid oxidation (PV and TBARS) varied most in the first part of the storage period, 24 hours for
5 °C and 2 weeks for -10 °C, but remained stable thereafter. During the first part of the storage period, oxidation developed
differently in the different minces while the three minces showed the same oxidation pattern during prolonged storage. The
samples stored at 5 °C were more heavily oxidized than samples stored at -10 °C. In contrast to lipid oxidation free fatty acids
content was higher in minces stored at -10 °C than minces stored at 5 °C. A decrease in protein solubility was also observed
in the first part of the storage period for all products and for both temperatures. With respect to the color development a significant decrease in the a value (redness) and an increase of b value (yellowness) was observed during storage at 5 °C. These
changes were less pronounced during storage at -10 °C.
Lipid oxidation kinetics seemed to be dependent on product type only during the first part of the storage period. However, development of lipid oxidation in horse mackerel minces was found to be mostly affected by the storage temperature. The initial fat
content and oxidation level did not seem to affect the oxidative stability of the different minces during prolonged storage.
44
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
Advances in processes and added value of products
Some practical observations on lipid oxidation
in post-mortem fish muscle
Hultin H.O.
University of Massachusetts/Amherst, Department of Food Science, Gloucester Marine Station, POB 7128, Gloucester, Massachusetts, USA
01930
T
he classical kinetic scheme of the free radical pathway of lipid auto-oxidation, including the initiation, propagation, branching
and termination steps, has been widely used to both explain results and to devise experimental protocols for evaluating lipid
oxidations. This model may not be the most appropriate one to use in many food tissue systems. The phospholipids of cellular
membranes are the most susceptible lipids to oxidation in the tissue and have very different structure than bulk triacylglycerols. Most likely the initial oxidation step is the activation of molecular oxygen. Various iron compounds react rapidly to reduce
molecular oxygen to reactive species. Lipid peroxides found in vivo or post-mortem constitute a source of potential oxidative
breakdown products and thus serve net only as activators of pro-oxidants but also as substrates of the reaction.
Hemoglobin and perhaps other heme proteins appear to be the most important catalysts for lipid oxidation in fish muscle.
They break down preformed lipid hydroperoxides which produces additional radicals which lead to additional chain reactions.
Breakdown products are limited, however, due to the high number of free radical scavengers present in the muscle tissue, especially the sulfhydryl groups of muscle proteins. The amount of oxidation is related to the amount of hemoglobin present, i.e.,
the iron compounds often act more as reactants than as true catalysts. The reactivity of fish hemoglobins is highly dependent
on the pH since at low pH hemoglobin is activated by dissociation and the release of its heme moiety into the membrane lipid.
The large increase of lipid oxidation on mincing fish tissue is greatly accelerated by mixing the extracellular hemoglobin with
the intracellular lipids. The reaction of hemoglobin with preformed lipid hydroperoxides is rapid. A one min. exposure of blood
on the surface of a mackerel fillet reduced the storage time of the frozen fillets significantly. If heme protein-catalyzed oxidation
is avoided, low molecular weight iron could contribute to the oxidation, although at a much slower rate. A trimolecular complex
of iron ion with a nucleotide and histidine produces a maximal rate of oxidation in a model system. Ferric ions receive electrons
from NADH and oxidize the lipids of the membrane bilayer. Histidine is present at high concentrations in pelagic species which
are susceptible to oxidation.
Homogenization or post mortem aging can cause fragmentation of the cellular membranes causing some expansion of the
phospholipid headgroups of the bilayer making it easier for oxidants to access the membrane lipids. Exposure to relatively low
pH values can modify the composition and structure of the membranes, making them less susceptible to oxidation. Powerful
antioxidant systems exist in the muscle tissue of many species; it is an advantage to maintain them during processing and
storage. Although studies of antioxidants in model systems can provide valuable information, it is suggested that more complicated systems that bear a greater resemblance to the product in which the antioxidants will be used can provide critical
information.
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
45
Advances in processes and added value of products
The role of volatile compounds in odor development during
haemoglobin-mediated oxidation of cod muscle membrane lipids
Ólafsdóttir G.*, Jónsdóttir R., Bragadóttir M.
Icelandic Fisheries Laboratories, Skulagata 4 101, Reykjavik, Iceland
T
he aim of the project OXIFISH is to study the effect of heating and oxidation on phospholipids, proteins and antioxidants in
fish muscle, influencing sensory quality. A phospholipid model systems from cod has been used to study the effect of prooxidants (hemoglobin from cod and trout) and antioxidants in aqueous fraction of fish muscle (cod and capelin).
The development of volatile degradation compounds in the model system during chilled storage in ice were studied by sensory
analysis, traditional lipid oxidation analysis (TBARS) and extraction of volatiles by solid phase microextraction (SPME) followed
by gas chromatography analysis (GC-O, GC-FID, GC-MS) to identify volatile compounds.
The most potent odors detected in the model system were malty, sweet and caramel like odors contributed by 3- methylbutanal,
2,3-pentandione and 1-penten 3-ol, grass odor contributed by hexanal, rancid, potato like odor by cis-4- heptenal and heptanal,
mushroom odor caused by 1-octen-3-ol. Furthermore, rancid, fatty, soapy and lemon like odors indicated the presenceof well
known oxidation products like 2,4-heptadienal. Cucumber like, sweet, floral and rancid odors were dominating the aroma profile
of the cod muscle system but the identity of all the compounds has not yet been established. The correlation between these
analysis will be studied to better understand the kinetics of oxidation processes leading to rancidity in fish muscle and to explain
factors reducing the shelf life of chilled fish products.
The outcome of the project is increased knowledge on oxidation in fish muscle to underpin the development of healthy and tasty
fish products of high sensory quality and nutritional value to fulfill the needs of consumers.
46
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
Advances in processes and added value of products
« Fish shelf life prediction program » (FSLP) a tool
for predicting the shelf life of fresh fish
Alfaro B.1*, Nuin M.1, Pin C.2, Le Marc Y.2
1. AZTI-Tecnalia Spain
2. Institute of Food Research United Kingdom
T
he quality of a fish product and the shelf life is strongly dependent on its temperature history, from production, through distribution and storage to consumption. Fish shelf life is influenced by a number of factors, such as initial microbiological quality,
season condition,catching methods, handling, processing and storage conditions. Temperature abuse during any stage of the
distribution chain usually affects both safety and quality of fish. In this context, the aim of the present work was to develop a
user-friendly software able to predict the shelf life of farmed fresh fish according to the microbial growth but also to sensory evaluation. Besides, the efficiency of various time temperature integrator (TTI) devicesto predict shelf life has been evaluated.
Data were generated in experiments with turbot samples (Psetta maxima) obtained directly from aquaculture, and packaged in
extended PVC film. Microbial growth and sensorial characteristics were monitored in samples stored at controlled isothermal
conditions 0, 5, 10 and 15ºC in incubators (Ibercex V-450). Dynamic storage experiments were also conducted by storing the
turbot samples, at controlled non-isothermal conditions. The response ofthree types of TTIs, Monitor Mark® (3M, USA), Fresh
Check® (TempTime, USA) and Check Point® (Vitsab, Sweden), were measured at the same temperatures. TTIs were adequately activated just before introducing them in the incubator chambers, and responses of 10 TTIs of each type were measured
for replicates at each time.
The model of Baranyi and Roberts was fitted to the bacterial growth curves. The rate of change of the colour parameters was
estimated by fitting empirical models to each set of TTI colour measurements in time. The trained sensory panel scores were
analysed by principal components analysis. The first principal component represented 97% of the total variability and was used
as a global sensory indicator. The maximum specific bacterial growth rate, the rate of change of the colour parameters and the
rate of change of the sensory indicator were modelled as a function of temperature by fitting the Arrhenius model. Models were
validated in dynamic temperature conditions comparing the predicted and the measured values for all microbial, sensory and
TTI response parameters.
A software called «Fish Shelf Life Prediction Program (FSLP)» was developed as a user-friendly Excel add-in. This software allows predicting sensory acceptability, growth of spoilage bacteria in fish products and the response of TTIs at constant and fluctuating temperature conditions. At present, these models and software are being validated for other kind of seafood products.
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
47
Advances in processes and added value of products
Quality aspects of injection-salted and cold-smoked
pre-rigor Atlantic salmon (Salmo salar) fillets
Birkeland S.1*, Akse L.2, Skåra T.1
1. Norconserv AS Seafood Processing Research, NielsJuelsgate 50, P.O. Box 327, N-4002, Stavanger, Norway
2. Norwegian Institute of Fisheries and Aquaculture Research Seafood and Industrial Processing, Muninbakken 9-13, P.O. Box 6122, 9291
Tromsø, Norway
N
ew and improved slaughtering procedures in the salmon industry have increased the time elapsed before the onset of rigor
mortis and a potential for early (pre-rigor) processing, such as salting and cold-smoking, has emerged.
The physiological status of the raw material (rigor-status) has a significant effect on the uptake and distribution of salt in salmon
fillets if the infusion of salt into the muscle tissue is dependent on diffusion (e.g. dry- and brine-salting). Pre-rigor fillets have a
lower uptake and a less homogenous distribution of salt compared to fillets dry- or brine salted in-rigor or post-rigor state. Thus,
injection-salting was chosen as salting method in the present experiment.
Pre-rigor fillets of Atlantic salmon (3-4 kg) were injection-salted (4-6 h after slaughter, 25% brine, 1.5 bar, 30 needle strokes × min-1,
0.4 L brine × needle-stroke-1) and immediately cold-smoked or stored chilled (4 d, 3-4 °C) before smoking. An additional group
of fillets were filleted pre-rigor, stored chilled (4 d, 3-4 °C) and subsequently injection-salted and cold-smoked post-rigor as a
simulation of the present commercial practice for production of smoked salmon. All fillets were cold-smoked at identical conditions (chamber temp; 27 °C, relative humidity; 45%, air speed; 0.4-0.8 m × s-1) where the total drying- and smoking time was
180 min and 300 min, respectively, and stored vacuum-packaged (14 d,3-4 °C) prior to analysis. The major quality parameters
investigated were muscle gaping, surface colour, texture, exudates in vacuum, fillet contraction, processing yield, salt content
and distribution, sensorial and microbiological parameters.
The results show that injection-salting is highly suitable for production of early (pre-rigor) processed smoked salmon. The postrigor fillets are less suited for injection-salting than pre-rigor fillets due to a higher severity of muscle gaping. No major differences in the other investigated quality parameters were observed between the two variants of early processed smoked salmon
and the post-rigor group simulating the present commercial practice for production of cold- smoked salmon.
48
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
Advances in processes and added value of products
Muscle quality and storage stability
of farmed cod (Gadus morhua L.)
Herland H.*, Esaiassen M., Olsen R. L.
Fiskeriforskning Norwegian College of Fishery Science
C
od farming is a new and developing industry, raising a lot of questions to be answered. Farmed cod does not have the
same quality as wild cod. Parameters like pH and amounts of trimethylamine oxide (TMAO) and trimethylamine (TMA) are
shown to be different in farmed and wild cod. Since these factors may affect the storage stability, the aim of this work was to
compare the storage stability of wild and farmed cod.
Wild-caught cod and farmed cod were killed, gutted and stored in ice for upto 16 days. Samples were taken during the storage
period for analysis of total viable counts (TVC), specific spoilage bacteria (SSO, Shewanella spp. and Photobacterium phosphoreum), pH, TMA, TMAO, water content and water holding capacity (WHC).
The pH and water content were higher in wild cod than in farmed cod, and both parameters showed a slight increase during
the storage period for both groups of fish. The TMAO level was almost 10 times higher in wild than in farmed cod. The WHC
changed differently in wild and farmed cod during the storage period. In wild cod, the WHC decreased during storage while in
farmed cod it increased.
The major specific spoilage organism (SSO) in wild cod stored in ice has been shown to be sulphide producing bacteria, SPB
(Shewanella spp.). In farmed cod however, the results showed that P. phosphoreum is far more abundant than SPB and possible the major SSO. SPB were not detected in the farmed cod this experiment. The absence of SPB has also been reported
by other authors using farmed cod from other commercial producers. The TVC were at the same level for the two groups in
the beginning of the experiment. The TVC increased more in wild cod than farmed cod leading to a 2 log units difference in the
end of the storage period.
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
49
Advances in processes and added value of products
Protein oxidation of rainbow trout muscle during frozen
storage and identification of carbonylated proteins
Kjærsgård I. V. H.­1*, Nørrelykke M.R.2, Baron C.P.1, Jessen F.1
1. Danish Institute for Fisheries Research, Department of Seafood Research, Søltofts Plads, Building 221 Lyngby, Denmark DK-2800
2. Danish Technological Institute, Department of Applied Food Technology, Holbergsvej, 10 Kolding, Denmark DK-6000
T
he aim of this study was to evaluate how frozen storage at different temperatures affects protein oxidation and to identify
some ofthe proteins prone to oxidation. Frozen storage of fish is known to enhance lipid oxidation thereby resulting in the
development of an unpleasant rancid taste and odor. Frozen storage of fish is also known to reduce protein solubility and proteins are expected to be oxidatively modified.
Generally protein oxidation leads to a wide range of modifications; the most studied being the formation of carbonyl groups e.g.
aldehydes (RCOH) and ketones (RCOR) on proline, argenine, lysine or threonine. By labelling these carbonyl groups with 2,4
dinitrophenylhydrazine (DNPH) spectrometric or immune-chemical methods can be applied to measure the carbonylation/oxidation level.
In the present work, protein oxidation/carbonylation was evaluated by UV-spectrophometric and 2D-gel-electrophoresis immune-blotting. In order to estimate the total oxidative level, fish lipid oxidation was followed simultaneously.
The experiments revealed that frozen storage at -20 ºC gave an increase in protein carbonylation of rainbow trout muscle and
induced changes in protein solubility compared to storage at -30 ºC or -80 ºC. Furthermore,low-salt-soluble proteins extracted
from fish that were either fresh orstored for three years at -80 ºC had a similar degree of carbonylation. To enable a better
understanding of the nature of protein oxidation proteome analysis and 2D-immune-blotting was conducted on muscle proteins
and several of the oxidized proteins were identified by LC-MS/MS.
The results give an estimate of the level of protein carbonylation in rainbow trout after frozen storage and in fresh fish and
shows that for a distinct number of proteins oxidation increases during storage. Furthermore it is observed that low- abundant
proteins can be relatively more carbonylated than high-abundant proteins, thereby indicating that some proteins are more susceptible to oxidation than others, either due to their cellular localization, amino acid sequence or biochemical function.
50
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
Advances in processes and added value of products
Post-mortem changes in Norway lobster (Nephrops
norvegicus) – possible reasons for the absence of the
rigor-mortis state and the relative short shelf life
Gornik, S.*, Albalat, A., Neil, D.M., Coombs, G.H.
Institute of Biomedical and Life Sciences, University of Glasgow, Glasgow, G12 8QQ Scotland, United Kingdom
I
t is known that post-mortem changes taking place during handling, processing and storage are important for the quality and
shelf life of both meat and white fish, and that these changes are greatly affected by pre-slaughter stresses. In contrast,
knowledge of the post-mortem changes in commercially important crustacean species is poor; for example, the rigor mortis
state, which is a major quality factor in fish, has not been investigated in many crustaceans. More detailed knowledge of the
post-mortem changes in crustaceans will lead to improvements in catching, handling, processing and storage, thus yielding
longer lasting freshness and a longer shelf-life.
The most valuable crustacean fishery in the UK is for Norway lobsters (Nephrops norvegicus) with an annual total allowable
catch of ~50,000 t, which has a value of ~£50M at first sale. However, the post mortem changes in this species have not yet
been described, and the rigor mortis state appears to be absent. A study has therefore been performed to determine the biochemical changes that occur in the tail meat of N. norvegicus post-mortem, and to examine the rigor mortis condition. The
muscle tissue metabolites glycogen, D-glucose, L-lactate, ATP and its breakdown products were measured at different times
post-mortem, and a method for the continuous monitoring of tissue pH was employed. Changes in muscle protein composition
were also monitored using scanning image analysis and SDS-PAGE. Using these measures, the effects of different pre- and
post-mortem stressors such as starvation, exercise and post-slaughter storage temperature were examined.
The results show that the initial glycogen concentrations, L-lactate production, pH changes and ATP breakdown processes are
closely linked. Pre-slaughter stressors cause the depletion of glycogen stores and the accumulation of L-lactate, and therefore
have a significant effect on post-mortem events. Post-slaughter storage temperature also affects these post-mortem changes,
and appears to be the main influence on both muscle protein degradation and pH increase. In fact a high rate of muscle protein degradation in relation to the rate of depletion of ATP in N. norvegicus tails may explain why the characteristic stiffness of
muscle in the rigor mortis state is not apparent in this species. The generally low amounts of acidic L-lactate produced and a
simultaneous basic ammonia production during the ATP breakdown are furthermore responsible for a significant pH increase
in a relative short amount of time. The increased pH also facilitates the growth of spoilage bacteria.
Our findings for the first time describe post-slaughter physiological changes in N. norvegicus. Future work will concentrate on
linking these findings with possible texture changes and later consequences for the quality of this particular crustacean shellfish.
This work was supported by a grant from the EU Financial Instrument for Fisheries Guidance (FIFG) Scheme through the
Scottish Executive, and by Young’s Bluecrest Seafoods Ltd.
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
51
Advances in processes and added value of products
Rheology of surimi-based products from fatty fish underutilized by
the industry: Argentine croaker (Umbrina canosai, Berg 1985)
Lempek T., Prentice C.*
Laboratory of Food Technology, Marine Products Processing Research Program, Department of Chemistry, FURG, University of Rio Grande
P. O. Box 474, 96201-900, Rio Grande RS, Brazil
S
urimi consists of a fish wet muscular protein concentrate, without flavor and odor and with high water absorption capacity
and gel quality. A promising option would be the elaboration of products differentiated from surimi of the Argentine croaker
(Umbrina canosai), a sufficiently abundant fish in the coast of Brazil south, but underutilized and of low commercial value for
the high content of lipids that presents. Amongst the products that could be elaborated to leave of this raw material, cite the
sausages that, besides being one of the forms oldest of the processing of meats, they possess great acceptance at South
Brazil. One of the more important technological problems in the sausage processing is the water and fat setting. This problem
can be minimized with the appropriate additive use contributing in the formation of the gel and the stabilization of the protein
matrix providing quality of sliced, better emulsion stability and bind capacity. Soy protein is an additive used for the meat industry that improves the emulsifying action and leads to the stabilization of the pasta. Potato starch does not influence on the
structure of the pasta, but it increases the consistency due to water setting. The temperature is a determinative factor in the
formation and stabilization of the emulsion since surimi presents different behavior in different temperatures. The present work
had as objective to evaluate the influence of the soy protein, potato starch and heating temperature in the texture of a emulsified sausage processed from surimi of Argentine croaker. For this an factorial planning was carried through where the optimal
parameters of processing had been gotten: soy protein 1.79%, potato starch 6.97%, heating temperature 83.91 ºC, being the
answer variables (gel force, cohesiveness, elasticity) measures in a Tests Universal Machine Instron. The formation tax and the
firmness of the gel had depended on the temperature, protein concentration and heating time. It could be concluded that the
cohesiveness diminishes with the increase of soy protein or increase of potato starch. Further research is needed to optimize
the surimi processing system using this fatty fish.
52
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
Advances in processes and added value of products
Effects of different capture methods on nucleotide breakdown
products in Norway lobster (Nephrops norvegicus) and
possible consequences for quality
Albalat A.1*, Gornik S.1, Crozier A.1, Atkinson R.J.A.2, Coombs G.H.1, Neil D.M.1
1. Institute of Biomedical and Life Sciences, University of Glasgow, Glasgow, Scotland United Kingdom G12 8QQ
2. University Marine Biological Station (UMBS) Millport, Isle of Cumbrae, Scotland, United Kingdom
N
orway lobster (Nephrops norvegicus) fisheries have developed quickly since the 1960’s and the total allowance catch for
2006 in European waters has been set to more than 50,000 tonnes. Trawling is the most common method of capture,
accounting for ~95% of the landings, and the remaining ~5% are traditional creel-caught landings. The animals are sold into
three markets, as frozen tails, as whole animals (fresh or frozen) or live animals. The first of these is supplied from trawling,
while the last two, which have higher value, are supplied by creeling. Animals coming from creels present a better condition
and are believed to have better quality. However if trawled animals are to be directed to higher value segments of the market
it is necessary to establish the condition of the animal after trawl capture compared to creeled animals, and to determine what
effects this may have on the quality.
Currently there is little information regarding the effects of the capture methods on the condition of this crustacean, and the
possible effects on the quality of the final product. Therefore, in the present study, we have compared the effects of different
capture procedures (creeling, or trawling for different periods of time) on the condition of the animal. This has been done by
the analysis of nucleotide breakdown products by HPLC, yielding the adenylate energy charge (AEC) and the K-value as a
freshness index for tails kept on ice for up to 7 days following the different capture methods.
The results show that trawled animals presented lower AEC values compared to creeled animals and to control animals held
in aquarium tanks. In fact, animals trawled for as short as 15 min presented adenosine monophosphate (AMP) rather than
adenosine triphosphate (ATP) as the main nucleotide, suggesting a very rapid breakdown of ATP in this species. K-values were
also affected by capture procedures, although trawling for different time periods did not affect significantly the freshness of the
tails held on ice for up to7 days. These measures of nucleotide breakdown products after capture have been compared with
measures of physiological stress such as haemolymph lactate concentration. The results suggest that during creeling anaerobic glycolysis is not the main metabolic source to obtain energy while trawling would be dominated by anaerobic glycolysis.
Our results demonstrate for the first time in Nephrops norvegicus that the ATP breakdown process and therefore AEC are highly dependent on the capture procedure. The data obtained suggest that K-value is less dependent on the initial condition of
the animals although care should be taken when targeting for premium prices, especially when live animals are involved.
This work was supported by a grant from the EU Financial Instrument for Fisheries Guidance (FIFG) Scheme through the
Scottish Executive, and by Young’s Bluecrest Seafoods Ltd.
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
53
Advances in processes and added value of products
The muscle extracellular matrix proteome of
Atlantic cod and spotted wolffish
Veiseth E.*, Tingbø M.G., Ofstad R., Hannesson K.O.
Matforsk AS Norwegian Food Research Institute, Osloveien 1, N-1430, Ås, Norway
P
ost-mortem softening of fish muscle and the occurrence of gaping are major concerns for the fish industry, and typically
lead to processing difficulties and reduced consumer acceptance of the products. Gaping occurs when elements within the
muscle’s connective tissue, more specifically the extracellular matrix (ECM), fail to hold the fillet together. The major constituents of the muscular ECM are collagens,g lycoproteins, and proteoglycans. Proteoglycans consist of a protein core with
varying amounts and types of covalently attached sulfated carbohydrate side chains (glycosaminoglycans; GAGs), and little is
known about the composition of proteoglycans in fish ECM. Thus, the objective of this study is to investigate the muscular extracellular matrix (ECM) proteome of Atlantic cod (Gadus morhua) and spotted wolffish (Anarhichas minor). These two species
are known to have different propensities to gape, and we have previously found that the ECM of cod and wolffish have different
GAG composition and sulfation degrees (Tingbø et al., 2005, 2006).
Muscle samples were extracted in 4M guanidine-HCl, followed by density gradient ultracentrifugation, after addition of CsCl2 to
a starting density of 1.37 g/mL. Following ultracentrifugation, the tubes were punctured in the bottom, and fractions with varying
density were collected. A sticky surface layer on top of the tubes was discarded, and fractions with densities above 1.34 g/mL
were pooled, dialysed against distilled water and lyophilised. Thes amples were resuspended in a sample buffer (7M urea, 2M
thiourea, 2% CHAPS, 1% DTT, 2% IPG buffer pH 3-10, 40mM Tris, pH 7.5), and separated by isoelectric focusing (pH 3-10)
followed by 12.5% SDS-PAGE. The 2-DE gels were silver stained and analysed for species differences using the Image Master
Software (Amersham Biosciences).
Results from the 2-DE show qualitative differences in protein expression between cod and wolffish ECM. Wolffish seem to have
more proteins in the acidic, low molecular weight area (pH 3.5-5; 10-15 kDa) than cod, while cod have more proteins in the
basic, high molecular weight area (pH 7-10; 35-70 kDa). Proteins that differ in cod and wolffish ECM will be identified by peptide
mass fingerprinting using matrix-assisted laser desorption/ionisation time-of-flight (MALDI-TOF) or de novo sequencing using
the MALDI-TOF/TOF mode (Bruker Ultraflex).
References
Tingbø, M.G., S.O. Kolset, R. Ofstad, G. Enersen, and K.O. Hannesson. 2005. Sulfated glycosaminoglycans in the extracellular
matrix of muscle tissue in Atlantic cod (Gadus morhua) and spotted wolffish (Anarhichas minor). Comp. Biochem. Physiol.,
140B: 349-357.
Tingbø, M.G., S.O. Kolset, R. Ofstad, G. Enersen, and K.O. Hannesson. 2006. Identification and distribution of heparan sulfate
proteoglycans in the white muscle of Atlantic cod (Gadus morhua) and spotted wolffish (Anarhichas minor). Comp. Biochem.
Physiol., 143B: 441-452.
54
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
Functional, innovative and
convenient seafood and
ingredients
Oral presentations
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
55
Functional, innovative and convenient seafood and ingredients
Keynote lecture
Uncovering bioactive ingredients in fish : beneficial effects
on obesity-linked insulin resistance and diabetes
Marette A.
Laval University Hospital Research Center
A
n increasing number of studies point towards an important role of fish nutrients in the modulation of insulin action in peripheral tissues, leading to improve glucose homeostasis and reduced risk of cardiovascular diseases in obesity. The
purpose of this presentation will be to discuss how these nutrients affect insulin sensitivity and the potential mechanism by
which they exert their beneficial action. Dietary interventions in animals fed fish oil induce major changes in glucose metabolism and lipid metabolism. Moreover, recent studies suggest that omega-3 fatty acids have anti-inflammatory effects in mutiple
chronic diseases including obesity-linked diabetes. Finally, fish proteins and amino acids are important modulators of glucose
metabolism and insulin sensitivity and recent studies indicate that they exert part of their effects via their ability to modulate the
mammalian target of rapamycin pathway.
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
57
Functional, innovative and convenient seafood and ingredients
Future priorities of research for healthy, safe and nutritious
seafood based on results from Seafood plus
Børresen T.
Danish Institute for Fisheries Research, Dept. of Seafood Research DTU, Building 221 Kgs. Lyngby, Denmark DK-2800
S
EAFOODplus is an integrated research project supported by the European Union under its Sixth Framework Programme. It
has 68 partners in17 countries. The research is organized in six main research areas containing a total of 20 projects, and
more than 200 researchers are involved. The strategic objective of SEAFOODplus is to reduce health problems and to increase
well-being among European consumers by applying the benefits obtained through consumption of health promoting and safe
seafood products of high eating quality.
The project has been running for more than two years, and the results are very encouraging and point at new priorities for the
next framework programme, as well as for overall priorities within the seafood area anywhere.
Some examples to be illustrated during the presentation include:
-A better understanding of how consumers perceive seafood, making it possible to implement new strategies for increasing consumption for the population groups needing it most.
-A new type of microorganism has been discovered that causes histamine poisoning in seafood even during storage at
low temperature. Based on this and other results from SEAFOODplus, new strategies must be developed for improving seafood safety.
-A breakthrough has been obtained in using farmed fish as a carrier for selenium in diet to humans. This principle must
be expanded to other nutrients of vital importance.
-Convincing results have been seen on how fatty acids in seafood reduce postnatal depression. More studies must be
directed towards psychological effects of omega-3 fatty acids in humans.
-In future more fish will be produced in aquaculture. The European consumer must be prepared to see new species for
sale in supermarkets, where the role of retailers must be investigated.
-In order to reduce obesity in the European population lean, nutritious food must be delivered. The taste must be good
and products must be developed that can be used for convenient preparation in busy households. Seafood is the obvious choice.
On the background of the examples an overview will be given of what should be the highest priorities within seafood research
in the future in order to deliver to the market safe, nutritious products with high eating quality.
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Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
Functional, innovative and convenient seafood and ingredients
Antioxidant activity of seaweed extracts in oil
Smith J.L.*, McLean C.H.
Novel Marine Extracts Seafoods & Marine Extracts Crop & Food Research Ltd.
O
ils containing long-chain polyunsaturated fatty acids are susceptible to oxidative degradation. Fish oils in particular are
highly polyunsaturated and are very sensitive to oxidation. This results in a loss of valuable fatty acids, and the development off-odours and flavours. In addition, the consumption of oxidised oils may have adverse affects on human health. There
is therefore a need to use antioxidants to preserve the quality of oils during storage. Chemically synthesised antioxidants are
effective in reducing or delaying oxidation, but there is some concern regarding their potential toxicity, and the use of synthetic
preservatives does not well fit with the production of all-natural health supplements. In this paper we describe the use of extracts, derived from seaweeds growing abundantly in New Zealand, as antioxidants. We identified that extracts from several different seaweed species had antioxidant activity in a chemical oxidation assay system (DPPH). We extended these findings by
preparing two extracts from each seaweed, aqueous and organic, and applied them to an accelerated storage trial of vegetable
oil. We observed that all the extracts applied to the vegetable oil substrate had antioxidant activity, as measured by peroxide
values (PVs) and anisidine values (AVs). Together, these results suggested that extracts from New Zealand seaweeds may
have potential as functional food additives.
Recently, we have applied the seaweed extracts in an accelerated storage trial of oils extracted from the New Zealand fin-fish
hoki (Macruronus novaezelandiae). In contrast to our findings in the vegetable oil trial, we found that some extracts increased
levels of oxidation products compared to the controls as measured by increased PV. We also observed high AVs in oils with
seaweed extracts. We discuss our findings in light of current research on naturally- derived products as antioxidants.
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
59
Functional, innovative and convenient seafood and ingredients
Development strategy for high omega-3 fatty
acid seafood products using fish mince
Lee C.1*, Joaquin H.1, Lee K.-H.2, Oliveira A.C.M.3
1. University of Rhode Island
2. Kyung Hee University Seoul, Korea
3. University of Alaska Fairbanks
I
n recent years there has been an increasing interest in introducing high omega-3 fatty acid seafood products other than
the whole fish for health concept, convenience and affordability. The pelagic fish species, primarily mackerel and herring in
Atlantic ocean, are the main source of omega-3 fatty acids besides salmon and tuna, and they are abundant and inexpensive.
However, the utilization of these species has been slow due to their flavor and stability problems. We have attempted to improve the flavor and stability without sacrificing the quantity and quality of omega-3 fatty acids using a mince-based nugget
product as a seafood model.
Atlantic mackerel or herring were filleted and mechanically deboned to produce a refined mince. The mince was cryostabilized
with milk protein concentrate (MPC) at 4% and blended with ingredients for flavor, texture and moistness improvements. The
mix was formed, lightly battered, flash-fried and stored frozen until texture and sensory analysis. The role of MPC in control of
lipid oxidation and fishy odor development was determined by monitoring changes inTBARS, omega-3 fatty acid profile (FAME
by GC) and fishy odor volatiles (headspace analysis by GC-MS) during 6 month frozen storage.
MPC was found to retard lipid oxidation with reduced TBARS, the usage level >4% being effective in frozen mince block. It
also appeared to control the enzymatic lipid oxidation in the freshly minced tissue based on changes in TBARS and fatty acids.
Fish mince-based nugget tends to get drier during serving and becomes less acceptable. The combination of diced moisturereleasing vegetable and milk improved moistness and texture allowing products to remain moist during serving. The mackerel
nugget from the median oily fish could potentially provide ~260 mg omega-3 fatty acids (10 mg LNA, 90 mg EPA and 160 mg
DHA) per piece (~20 g containing 10 g mince). This product contains omega-3 fatty acids comparable to or higher than omega3 oil enriched products (50 mg - 340 mg) currently in the Japanese market.
60
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
Functional, innovative and convenient seafood and ingredients
Antioxidant protection of minced fish muscle by white grape pomace
Borderías A.J.1*, Sánchez-Alonso I.1, Jiménez-Escrig A.1,
Saura-Calixto F.1, Larsson K.2, Undeland I.2
1. Instituto del Frío (CSIC) Madrid, Spain
2. Chalmers University of Technology, Göteborg, Sweden
T
he aim was to study the antioxidant effect of addition of white grape antioxidant dietary fibre (WGDF), isolated from grape
pomace, on the prevention of lipid oxidation in different fish muscle systems. For the study, minced horse mackerel muscle
and a washed cod mince model system fortified with hemoglobin (Hb) were used.
WGDF was extracted following a patented method and contained 7.85% of extractable polyphenols. As measured by the FRAP
and ABTS methods, the antioxidant capacity of the WGDF was in the range of 285-466 micromol Troloxeq/g. Minced muscle
obtained from horse mackerel (Trachurus trachurus) was fortified with 2% (2-WGDF) and 4% (4- WGDF) of WGDF. Half of lot
2-WGDF was packed in vacuum (2-WGDF-vac). All samples were frozen stored for 6 months at -20 ºC. The model system consisting of washed cod mince with addition of trout Hb was used to test the capacity of white grape dietary fibre (2% and 4%) and its
ethanol extractable polyphenols (EPP) against Hb-mediated oxidation of fish muscle membranes during ice storage. The rate of
oxidation was monitored by conjugated dienes and trienes, thiobarbituric acid index, radical scavenging activity, ferric reducing
ability, redness (a*) loss and rancid odour.
Results from the minced horse mackerel muscle study showed high antioxidant capacity of WGDF; the development of conjugated dienes, trienes and aldehydes were inhibited significantly during the frozen storage period. Samples with 2% WGDF and
packed by vacuum were the most stable against lipid oxidation. Previous to storage, radical scavenging activity (ABTS) and ferric
reducing ability (FRAP) showed significant differences between the control sample (0-WGDF) and samples with added WGDF.
In the case of FRAP assay, the ferric iron reducing capacity was 166% (2-WGDF), 161% (2-WGDF-vac), and 267% (4-WGDF)
compared to that of the 0-WGDF sample. The same pattern was observed in the ABTS assay. During the whole 6-months storage
period, the WGDF-added samples continued having significantly higher values in both assays. However, there is a depletion of
effectiveness during the storage which is more evident during the first two months in the case of samples with added dietary fibre
(ranging 35% to 47%). In the case of the vacuum packed sample, this decrease was around 21%. At the end of the frozen storage
period, the following feature was maintained: the 2-WGDF and the 4-WGDF samples showed a double depletion in the mentioned
antioxidant values in comparison to the 2-WGDF-vac sample. After analyses in the cod model system fortified with Hb, it is possible to say that the EPP fraction is the more active antioxidant although the rest of WGDF also show some activity.
These results indicate that WGDF is effective in delaying lipid oxidation in the studied systems and hence could be used as an
ingredient to prevent oxidation in minced fish. The ethanol extract (EPP) is the fraction of the white grape dietary fibre which has
the highest antioxidant capacity in the model system.
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
61
Functional, innovative and convenient seafood and ingredients
Use of protein additives in gels from previously
cooked Jonah crab (Cancer borealis) minced meat
Baxter S.R.*, Skonberg D.I.
Department of Food Science and Human Nutrition, University of Maine, 5735 Hitchner Hall, Orono, ME USA, 04469
L
arge quantities of edible by-products are generated in crab processing, much of which goes to waste or is underutilized.
One such product, fully cooked crab meat mince, is currently under investigation for its use as a primary ingredient in valueadded food products. The gelation properties of muscle proteins are crucial in the formulation of nuggets, sausages, and other
protein gel-based products.
Previous research conducted in our lab showed that previously cooked, washed Jonah crab mince will form gels upon further
heat treatment. The current study focused on the use of protein additives to modify the water holding capacity and textural
attributes of the crab mince gels.
Frozen, previously cooked Jonah crab (Cancer borealis) mince was thawed and washed. After washing, one of five treatments
was applied to the mince: control (no additive), 5% soy protein isolate, 10% soy protein isolate, 5% whey protein isolate, 10%
whey protein isolate, 5% dried egg white, 10% dried egg white. The protein additives were incorporated into the washed mince
and the moisture was adjusted to 80%. Treated mince was stuffed into cellulose casings and cooked for 30 minutes at 35 °C
followed by 30 minutes at 90 °C. Gels were tested for water holding capacity, and a texture analyzer was used to determine
force to fracture, distance to fracture, hardness, fracturability, springiness, and chewiness. To determine preferred textural characteristics, texture measurements were compared with those of preferred products as identified by a consumer focus group.
All protein additives decreased the water holding capacity of the gels except for 5% soy protein isolate, which was comparable
to the control. Whey protein isolate interfered with gel formation and inadequate gels were produced, therefore data for the
whey protein gels was not included in textural analysis. The addition of 10% egg white resulted in a force to fracture statistically
the same as the control, whereas all other additives decreased the force to fracture. The control had the greatest distance to
fracture and the addition of 10% soy protein isolate resulted in the shortest distance to fracture. The results indicate that soy
protein isolate and egg white can be used to alter textural characteristics of gels from previously cooked Jonah crab to meet
consumer preferences.
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Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
Functional, innovative and convenient seafood and ingredients
The effect of molecular characteristics of chitosan on its ability
to bind fat in an in vitro simulation model for digestion
Helgason T.1, Weiss J.2, McClements D.J.2,
Gislason J.3, Einarsson J.M.3, Kristbergsson K.1*
1. Dept. of Food Science and Human Nutrition, Univ. of Iceland, Hjardarhagi 2-6, Reykjavik, Iceland, 107
2. Univ. of Massachusetts/Amherst, 238 Chenoweth Lab, Box 31410, Amherst, Massachusetts, USA 01003
3. Genís ehf. Mýrargata 2, Reykjavík, Iceland, 101
C
hitin is the second most abundant biopolymer in nature after cellulose. It is the main structural constituent of the protective
shell in insects and crustaceans, like shrimp and lobster. The properties of chitin and chitosan are highly dependent on
the physico-chemical nature of the polymers. Currently applications have been reported in agriculture, foods, cosmetics and
its properties are being investigated for both medical and pharmaceutical applications. Approximately half of the chitosan produced is being sold as a dietary supplement due to suggested lipid binding and hypocholesterolemic properties. Reports from
clinical research on the effect of chitosan on fat absorption in humans have been conflicting. Some researchers have reported
reduction in body fat in patients taking chitosan prior to food intake while other research groups have not observed a significant
effect in there trials.
The relationship between the fat binding capacity of chitosan and its molecular characteristics (molecular weight and charge
density) was examined using an in vitro digestion model. This model involved adding different concentrations (3 to 10 wt%) of
oil droplets to a 0.1 wt% chitosan solution at pH 3 to simulate consumption of a fat containing meal after ingestion of chitosan.
The fat binding capacity increased with decreasing molecular weight (MW) and with increasing degree of deacetylation (DDA):
approximately 132, 85, and 78 g of oil per g of chitosan for MW’s of 200, 500 and 750 kDa (all 90% DDA), respectively; and,
47, 65, and 78 g of oil per g of chitosan for DDA’s of 40%, 70% and 90% (all 750 kDa), respectively. In addition, the extent of
droplet aggregation and the nature of the aggregates formed (strong versus weak; large versus small) also depended on chitosan characteristics. Chitosan-oil complexes were also analyzed using confocal microscopy.
Our research indicates that the reactions are both highly dependent on the type and chemical nature of chitosan, environmental
conditions and the type of lipid involved. The results may have important consequences for understanding the biological activity
of chitosan, and for designing functional food ingredients to reduce lipid digestion and absorption.
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
63
Functional, innovative and convenient seafood and ingredients
Storage stability of frankfurter hake
sausages enriched in fiber
Cardoso C., Mendes R., Pedro S., Nunes M.L.*
Instituto Nacional de Investigação Agrária e das Pescas, INIAP/IPIMAR, Avenida de Brasília, 1449-006 Lisboa, Portugal
S
torage stability of two groups of frankfurter hake sausages (with no pork meat) and enriched in fiber was examined during
a two months period under refrigeration. These hake sausages are an innovative and healthy product, whose sensory
properties (odour, taste and texture) strongly resemble those of an ordinary frankfurter pork sausage. The formulation was
the same for all sausages with the exception of pork fat, present in one group (8%, w/w) and absent in the other, where it was
replaced by a combination of a special fibre (5%, w/w), which mimics the oily mouth-feel associated to fat, and an extra amount
of hake (plus 3%, w/w). The formulations also contained potato starch, pea fiber, whey protein, NaCl, ascorbic acid and polyphosphates. Samples were cooked at 75 ºC for 15minutes, cooled, vacuum packaged, heat-processed during 10 minutes after
reaching an internal temperature of 90 ºC, cooled and stored under vacuum at 2-4 ºC. Formulations exhibited good thermal
stability, with process yields above 99% and purge losses not significant at the end of the study. Throughout the experiment,
sausages containing pork fat showed lower gel strength, however, were more elastic and cohesive than the other group sausages. As expected, for low fat products, TBARS values increased slightly over time and were always inferior to the ones found
in the other group. Onthe other hand pH and colour parameters remained constant. frankfurter hake sausages whether low fat
or not presented acceptable sensory scores until two months. Neither Enterobacteriaceae, spores of sulphite-reducing Clostridium nor yeast and moulds were detected during the storage of the sausages. Psychotropic and lactic bacteria were detected
albeit remaining close to the detection limit. Therefore, these products had good stability since they maintained favourable
quality attributes for two months. Furthermore these products can help to improve dietary fibre intake (an issue that has lately
deserved much attention since clinical trials data strongly suggest that dietary fibre can reduce the risk of colon cancer).
64
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
Aquaculture and
fish supply
Oral presentations
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
65
Aquaculture and fish supply
Keynote lecture
Sustainable Aquafeeds for the Provision of
Safe and Nutritious Aquaculture
Bell G.
Nutrition Group, Institute of Aquaculture, University of Stirlingz
T
he culture of carnivorous finfish in Europe, principally Atlantic salmon, rainbow trout, European sea bass and gilthead
sea bream, has meant that aquafeed formulations have contained relatively large amounts of both fish meal (FM) and
fish oil (FO) derived from marine feed grade fisheries. Fish meal and oil are obtained from feed grade fisheries that have
effectively reached their sustainable limits and have supplied ~6 m metric tonnes and ~1 m metric tonnes of FM and FO,
respectively, for the last 20 years. Current evidence suggests that salmonids can be grown on diets where 100% of the FO
is replaced by VO, or a VO blend, and that for bass and bream replacement of up to 60% of FO shows no detrimental effects on growth. However, use of such VO replacements can result in reductions of the essential n-3 fatty acids, DHA and
EPA, of between 50-65% although these values can be restored to 70-100% of the values in fish fed FO by the use of FOcontaining finishing diets www.rafoa.stir.ac.uk. Such high levels of FO replacement can only be used provided essential fatty
acid levels are maintained by the inclusion of adequate FM levels. Thus, while trout and bream can be cultured with 75%
replacement of FM, with no loss of growth performance, this has only been done where FO has been used as the oil source
www.st-pee.inra.fr/ici/stpee/nut/peppa/peppa.htm. Clearly, simultaneous reductions in FM and FO will require considerable
care if fish health and welfare, as well as product quality are to be maintained. Nowadays, the efficacy of EPA and DHA, in the
prevention or modulation of many of the inflammatory conditions prevalent in the developed world is well established. However,
there is also concern that the levels of dioxins, PCBs and polybrominated dephenylether (PBDE) flame retardants, as well as
the presence of toxic metals, present a potential risk to human health. The nutrients, as well as contaminants, found in the
edible parts of fish are derived largely from the feed and this means that farmed fish can be tailored to provide optimal levels
of fatty acids, vitamins and minerals for human consumption. In addition, careful selection of aquafeed raw materials allows
levels of undesirable substances present in the fish, at harvest, to be controlled. The International Society for the Study of
Fatty Acids and Lipids (ISSFAL; www.issfal.org) recommend consuming 500mg of EPA + DHA, or 3.5 g/week to provide good
cardiac health in adults. This weekly intake value can be provided by consuming 200g of salmon cultured on diets containing
FO although 200g of salmon cultured using 75% VO provides only 1.6g EPA + DHA. However, after a 20 week pre-harvest FO
finishing diet period, the EPA + DHA content of a 200g portion was increased to 2.7g. The EU have recently revised their limit
values for organic contaminants in aquafeeds and fish produce to include dioxins/furans and dioxin-like PCBs. These combined
limits have been set at 7 ng TEQ/kg for fish feeds and 8 ng TEQ/kg for fish products for human consumption. New methods
to reduce organic contaminanats in FO are being developed and >90% of dioxins and PCBs can be removed with only minor
increases in costs. Future strategies for aquaculture production must aim to reduce current dependence on FO and FM, take
steps to reduce contaminant levels in feed and fish and, at the same time ensure that current levels of n-3 highly unsaturated
fatty acids in farmed fish are preserved.
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
67
Aquaculture and fish supply
Implication of collagen and hydroxylysyl pyridinoline
cross-link compartments on the texture
of Atlantic halibut (Hippoglossus hippoglossus L.) muscle
Hagen Ø.1,2*, Johnston I. A.1, Solberg C.2
1. School of Biology, University of St Andrews, St Andrews, Scotland, United Kingdom KY16 8LB
2. Department of Fisheries and Natural Sciences, Bodø University College, Bodø, Norway NO-8049
T
he objectives of the present study was to look into the collagen (HYP) and hydroxylysyl pyridinoline cross-link (PYD) compartments, reveal potential sexual differences, seasonal variations, and how this affects the flesh texture in farmed Atlantic
halibut. The fish used in the present trial was provided by Aga Marin A/S located at Dønna (Norway) and 20 fish were sampled
once every third month during a one year production period from Aga’s commercial production. The post- rigor fillets, dorsal
and ventral side, were homogenised and measured into 1 gram tubes which were stored at -80 ºC until analysis. The assays
were carried out using a newly established method (Li et al. 2005) for identification of the iminoacid hydroxyproline and PYD
fraction using a HPLC system from Varian with a fluorescence detector (ProStar). This method is based on previously published
methods (Eyre et al., 1984; Black et al. 1988; Bank et al. 1996) and is designed for quantification of HYP and PYD in fish. The
ProStar workstation software was used to identify and quantify the components based on the standard curves made of collagen
hydrolysate (Sigma) and purified PYD. The instrumental texture measurements, preformed with a TD-HDi Texture Analyzer,
displayed a variation in texture through the year and the collagen and PYD cross-link fraction showed the same pattern, being
at the lowest level in the winter. The result shows that male halibut displays a slightly tougher texture then females, but it is
not significantly. The difference in toughness is reflected in a higher alkaline insoluble collagen content in males, but not significantly different from females. Alkaline insoluble collagen fraction, which are believed to contain the PYD fraction, shows a
positive correlation (r2=0.25, P=0.0001) to flesh texture, when all replicates pooled together (n=100). PYD concentration shows
an even stronger correlation to texture, explaining 67.5% (r2=0.675) of the total variation (P=0.0001, n=100).
In conclusion, collagen and especially PYD concentration are positively correlated with the flesh firmness of Atlantic halibut.
The mature PYD cross-links are indeed important for the stabilisation of the collagen molecules and contribute to the mechanical strength of the collagen compartment of the extra cellular matrix.
References:
Bank, R. A., Jansen, E, J. Beekman, B., Koppele, J.M.T. 1996. Amino acid analysis by reverse-phase high- performanse liquid
chromatography: Improved derivatization and detection conditions with 9-fluorenylmethyl chloroformate. Anal. Biockem. 240,
167-176.
Black, D., Duncan, A., Robins, S. P. 1984. Quantitative analysis of the peridinium cross.links of collagen in urine using ionpaired reversed-phase high-performance liquid chromatography. 169, 197-203.
Eyre, D.R., Koob, T.J., Ness, K.P. 1984. Quantification of hydroxypyridinium cross-links in collagen by high- performance liquid
chromatography. Anal. Biochem. 137, 380-388.
Li, X., Bickerdike, R., Lindsay, E., Campbell, P., Nickell, D., Dingwall, A. Johnston, I.A. 2005. J. Agri. Food Chem. 53, 68446850.
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Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
Aquaculture and fish supply
Influence of technological parameters, fat content and
size on liquid leakage in cold-smoked salmon
Nielsen J.*, Loje H.
Danish Institute for Fisheries Research
C
old-smoked salmon is a highly valued product. However, within the recent years, the salmon industry has faced new problems such as high frequency of gaping, low and uneven colour distribution and liquid leakage in the smoked product.
When liquid leakage is apparent in the consumer packages, it is not acceptable for the producer and less acceptable for the
final customer. The result is that the image of cold-smoked salmon in some cases is declining and cold-smoked salmonis no
longer regarded as a high quality product. Today mainly farmed salmon are used in the European smoking industry instead of
the traditional wild salmon. The farmed salmon has a higher fat content than the wild salmon, and while a wild salmon has lipid
content under 10%, the farmed salmon might have lipid content over 20%.
The influence of fat content and size of salmon on liquid leakage in fresh and cold-smoked salmon was examined in parallel
with a crossover study of two salting and two smoking methods (automatic/traditional oven). In the first experiment, two groups
of salmon were used; one group of small salmon (size 3-4 kg) and one group of large salmon (size 6-7 kg). In each group there
was a group of salmon with high fat content and a group of salmon with lower fat content. The smoked samples were taken out
for analysis after storage for 1, 11 and 20 days at 2 °C after smoking. The results showed effects of raw material and storage
time. The group of large salmon with a high fat content lost more liquid than the group of small salmon with lower fat content.
The highest liquid loss was seen after 20 days storage after smoking at 2 °C. More fat was lost with the liquid loss at day 20
than at day 1 and 11 after smoking. In the salting/smoking experiment were used salmon (size 3-4 kg) and although the fish
were one batch from the same farm the fish to fish variation were higher than the variation between methods.
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
69
Aquaculture and fish supply
Fish size influences the digestibility and availability of nutrients
from a potential alternative lipid source, Natunola omega-3 de-hulled
flax kernel, by rainbow trout, Oncorhynchus mykiss (Walbaum)
Stone D.A.J.*, Hardy R.W.
Aquaculture Research Institute Hagerman Fish Culture Experiment Station, University of Idaho, 3059-F National Fish Hatchery Road Hagerman,
Idaho 83332, USA
W
orldwide the production of finfish in aquaculture is increasing at a rapid rate. To sustain this rapid growth alternative
forms of oils and proteins to replace fish oil and meal must be found. Omega-3 de-hulled flax kernel may be a suitable
alternative to fish oil and a lesser extent protein from fish meal. Compared to typical flax meal, omega-3 de-hulled flax kernel
has a vastly improved nutrient profile and contains ~ 50% oil and ~25% protein. Importantly, approximately 50% of the oil is
composed of α-linolenic acid, a very desirable omega-3 fatty acid for rainbow trout production. The successful incorporation of
alternative ingredients into aquafeeds requires reliable nutrient apparent digestibility coefficients (ADC%). While the nutrient
digestibility of a particular ingredient is species dependent, intra-specific differences due to fish size for ingredient ADCs have
also been reported. Failure to account for differences in ADCs due to fish size when formulating commercial fish feeds may lead
to a reduction in nutrient digestibility, an increase in effluent output, and ultimately an increase in production costs.
The aim of this study was to investigate the differences in the digestibility and availability of nutrients from omega-3 de-hulled
flax kernel between fingerling (53g) and market-size (490g) rainbow trout. Rainbow trout were stocked into 575-L tanks (3 tanks/
treatment) supplied with flow through spring water (14.5 ºC). Fish were fed either a reference diet or a diet containing 30% of
the ground omega-3 de-hulled kernels combined with 70% of the reference diet, twice daily for 2 wks. Both diets contained
yttrium oxide (0.01%) as an inert marker. Feces were then collected from fish by manual stripping. ADCs for organic matter,
protein, lipid, energy, phosphorus and essential amino acids were calculated. There were significant differences in lipid and
phosphorus ADCs due to fish size (market-sized fish > fingerlings, P < 0.05). There were no significant differences for ingredient ADCs for any of the other nutrients. However, in every instance, the ADCs were numerically greater for market-size
fish than fingerlings. Combined with the differences in lipid and phosphorus ADCs, this indicates differences in digestive and
absorptive uptake rates of nutrients between the sizes of fish tested in this study. In conclusion the nutrient profile of omega-3
de-hulled flax kernel would suggest that this product has an excellent potential to replace significant quantities of fish oil and
partially replace fish meal protein in aqua-feeds for rainbow trout and other species of fish. With regards to fish size, the higher
availability of nutrients by larger fish has cost and effluent reduction benefits as most of the feed used in the production of fish
are fed to in the latter stages of the production cycle.
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Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
Aquaculture and fish supply
Proteomics, sensory profiling and multivariate data analysis
to find biomarkers: Inclusion of eating quality in breeding
programs of rainbow trout (Oncorhynchus mykiss)
Leth N.K., Hyldig G., Nedenskov K., Jessen J.F.*
Danish Institute for Fisheries Research, Dept. of Seafood Research, DTU, Building 221 Kgs. Lyngby, Denmark DK-2800
A
n overall objective in aquaculture is to find genetic markers for eating quality of farmed fish enabling the inclusion of desirable quality parameters as a trait in breeding programs. As a basis for this, it is essential to know the genes involved in quality. The aim of the present work was, therefore, to find potential biomarkers (proteins) for a number of eating quality parameters
in rainbow trout (Oncorhynchus mykiss) by studying the molecular mechanisms responsible for specific quality attributes. This
was done by relating the muscle proteome with measured sensory quality.
The rainbow trout was assessed by sensory profiling using specific attributes of odour, flavour and texture as descriptors of
the quality. The sensory profiling was performed by a tested and specifically trained panel consisting of 10 assessors who evaluated 16 descriptors on an unstructured scale. The muscle proteome was analysed by « peptide fingerprinting » using 2DE
(two-dimensional gel electrophoresis). Muscle proteins and peptides were extracted in a SDS containing buffer under reducing
conditions at pH 8.3. A mild digestion by trypsin was included in the extraction procedure. The extracts were subjected to 2DE1,
gels were Coomassie stained and the individual spots were quantified by image analysis using PD Quest (BioRad). The relation between spot quantities and each sensory attribute was established by multivariate data analysis - partial least squares
(PLS) regression and selection of significant spots2.
Of the 16 sensory descriptors, 13 were found to correlate to a pattern of a limited number of protein spots (5 - 24). In the PLS
regression models based on the selected spots only, the correlation coefficients were fairly high (0.59 - 0.83). In several models, the main part of the systematic variation in the sensory attributes was, furthermore, related to the variation in quantity of
the included spots. In the models of texture attributes, several of the selected spots were identified as myofibrilar proteins.
Based on these findings, it was concluded that the combination of proteomics, sensory analysis and multivariate data analysis
could reveal potential protein biomarkers for specific sensory attributes. The identities of these proteins disclose genes that can
potentially be used in breeding programs for certain quality traits.
1. Kjærsgård, I.V.K. and Jessen, F. Journal of Agricultural and Food Chemistry 51:3985-3991 (2003)
2. Martens, H. and Martens, M. Food Quality and Preference 11:5-16 (2000)
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
71
Aquaculture and fish supply
Live delivery of wild Alaska salmon and
its effects on seafood quality
Buckley M.K.
Digital Observer inc., Kodiak, Alaska, USA
A
laska has long been a world leader in wild salmon production, and its wild stocks continue to be healthy and robust. But in
recent years Alaska’s salmon industry has seen sharp declines in income due to explosive growth in the farmed salmon
sector. Some Alaska wild harvesters are now beginning to adopt technologies and techniques developed in the farmed salmon
industry. They do so to improve fish quality and fetch a higher price. Keeping wild salmon alive after they are caught in fishermen’s nets is integral to the process. This study, conducted between 2004-2006, examines how seafood quality improves when
these practices are adopted and provides information on cost-effectiveness.
72
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
Aquaculture and fish supply
The culture of the «rock crusher» : Innovative and
high-value products from wolffish aquaculture
Le François, N.R.
Université du Québec à Rimouski/MAPAQ, Centre aquacole marin de Grande-Rivière, 6, rue du Parc, Grande-Rivière (Qc) Canada G0C 1V0
W
olffishes are cold-water marine fish species displaying particular dispositions for domestication. It is one of few novel
marine fish of proven aquaculutre interest, that possess features similar to those that have contributed to the success of
the Atlantic salmon industry. However, contrary to salmon, this is a species custom-fit for the cold northern climates (sub-zero
environments). Research and private initiatives have rapidly brougt this species to commercial scale in Norway. Iceland and
Canada are newcomers seeking to establish wolffish production units on their territory. A brief outlook of the current and future
research orientations is presented (genetics, physiology, zootechnics, biotechnologies, marketing, economics).
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
73
Aquaculture and fish supply
Processing of zooplankton – Calanus finmarchicus – as raw material for fish feed
Eikevik T.M.*, Magnussen O.M.
Norwegian University of Science and Technology, Department of energy and process engineering
H
arvesting zooplankton can be one of the most important resources in the developing of fish feed for the aquaculture
industry in the future. The main challenges will be handling, preservation and proceeding. Results from earlier projects
have shown very high enzyme activity in the harvested plankton and the need for on-board desalting and stabilisation of the
catch is necessary. The focus in this paper has been on the processes after harvest as an effect of time and temperatures.
The harvested zooplankton has a large amount of sea water between the individuals. If this sea water is not removed, the salt
will penetrate into the solids. Measurements of dried whole Calanus and processed solids are well above salt values accepted
for fish feed. The effects of washing combined with water/salt water removal by external forces as centrifugation, mechanical
pressure etc. are tested. To stabilize the Calanus after catching there will be discussed several processes in this paper. These
processes are heating, quick freezing, storage and thawing before processing, drying at temperatures both below and above
the freezing point. The paper will describe a total system for on-board processing of Calanus.
74
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
Aquaculture and fish supply
Chilling before slaughter as a tool to reduce
stress and to improve product quality
Airaksinen S.1*, Aro T.1,2, Ruohonen K.1
1. Finnish Game and Fisheries Research Institute, Turku Game and Fisheries Research, Itainen Pitkakatu 3, Turku, Finland FIN-20520
2. MTT Agrifood Research Finland, Jokioinen, Finland FIN-31600
T
he slaughtering is a challenging step in the production chain of high quality fish especially during the warm seasons. Live
chilling has been shown to improve the product quality of Atlantic salmon (Salmo salar) and low stress levels are known to
have beneficial effects on the end product as well (Skjervold, 2004; Pottinger, 2001). At its best, live chilling could offer an alternative to the chemical tranquillisers and mitigate the stress responses of the fish during handling. However, the temperature
shock as such could also act as a stressor.
Live chilling of rainbow trout (Oncorhynchus mykiss) was studied as a potential mean to improve end product quality. Low
temperature exposure was hypothesized to enhance the product quality by reducing handling stress during the slaughter but
also the improvement of the freshness was expected by reducing the time of ineffective chilling of the iced fish in the boxes
after the slaughter. The experimental setup of 23 factorial design was usedto evaluate the effects of chilling (15 oC versus 5 oC),
stress (non-treated versus sedated) and exercise (rested versus exercised) on selected variables. The stress and muscle activity indicators were blood hematocrit, glucose, lactate and osmolarity values as well as muscle pH and nucleotide ratios. The
measured quality indicators were rigor progression and muscle texture, waterholding capacity, colour and freshness.
Results show that pre-chilling effectively reduced stress responses to the comparable levels observed in chemically sedated
fish. Furthermore, fish at low temperature were more tolerant to exercise whereas fish at higher temperature were clearly
stressed by the forced exercise. The decline of muscle pH and rigor progression followed similar pattern i.e., pH decline and
rigor stiffening appeared more slow in chilled, rested and sedated groups. The effects of pre-chilling were positive also on the
quality parameters measured. Improved water holding capacity and breaking resistance in pre-chilled fish was observed in
fresh fish and persisted also during storage for five days. IMP, the nucleotide indicating good fresh taste of a fish, was higher
in chilled fish only on day one.
Data presented suggests that live chilling can effectively inhibit the stress responses caused by the slaughtering procedures
and high temperatures. Optimal chilling can potentially benefit both the customer and the fish as a better quality product and
more ethical slaughtering procedure, respectively. However, a sub optimal temperature recruited for chilling can counteract
these benefits attained.
References:
Pottinger, T.G. (2001): Effects of husbandry stress on flesh quality indicators in fish. In: Farmed fish quality (Ed. S. C. Kestin
ja P. D. Warris), s. 145-160. Blackwell Science Ltd., Oxford, UK. Skjervold, P.O. (2002): Live-chilling and pre-rigor filleting of
salmonids - technology affecting physiology and product quality. Dr. agric. Thesis, Agricultural University of Norway
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
75
Aquaculture and fish supply
Improved quality with restricted
feeding of Atlantic salmon
Solberg C.*, Johnsen C.A.
Bodø Regional University, NO-8049, Bodø, Norway
S
almon farming has so far been focused against maximum growth, and little attention has been against the quality of the
fish. To elucidate the effect of less frequent feeding on the growth and flesh quality, a full scale experiment has been performed, where the number of meals has been reduced. Normally Atlantic salmon will be fed to satiation once a day when the
temperature in the sea is below 5 °C, twice a day at temperatures between 5 and 10 °C, and three times a day at temperatures
above 10 °C. This regime was compared to an alternative where feeding was restricted by means of reduced meal frequency:
at seawater temperatures below 5 °C the fish were fed to satiation once every second day, and above 5°C they were offered
one daily meal. All fish were given the same feed, and samples were taken to look for differences in proximate composition
and muscle cellularity.
The feeding trial was carried out under commercial conditions with four replicates in each group in 15*15 m sea cages with
23.000 fish in each of the eight sea cages. The trial started December 2004 when the fish weighed 1 kg, and terminated in
September 2005 when the fish had an average live weight of 4.5 kg.
As expected, fish in the restricted group grew slightly slower with a reduction in harvest weight corresponding to 10 days of feeding at the current growth rate. There were no differences in proximate composition, but the muscle structure were significant
different amongst the treatments. Restricted feeding resulted in higher muscle fibre number, with smaller diameter and higher
fibre density. The restricted feeding also resulted in a significantly higher texture measured as shear force and more intense
colour measured as a* and b* values with a Minolta chromameter.
Restricted feeding not only enhanced the muscle quality it was also found to be economical profitable for a fish farmer. Less
feed was used to produce the same quantity of fish. The feed:gain ratio was reduced from 1.09 to 1.07 and in a typical Norwegian fish farm this represents a reduction of 130.000 NOK in feed cost. In contrast, the cost for 10 days longer production time
is estimated to 30.000 NOK, not considering the fact that the restricted feeding regime also is less labour intensive.
76
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
Consumers, market and
sea products
Oral presentations
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
77
Consumers, market and sea products
Keynote lecture
Proven methods of developing successful new value added
seafood products in an ever changing market place
Sirois M.
Fishery Products International- USA, 18 Electronics Ave., Danvers, MA 01923
D
ynamic does not begin to describe the challenges that currently face new product developers within the seafood industry.
Issues such as health and safety, supply, farmed vs. wild, quality, rapidly changing food trends and the difficulty in meeting
the ever increasing expectations of consumers are just a few of the hurdles encountered along the way. A proven path of developing successful new seafood products in retail, clubs and foodservice utilizing culinary arts, food science and engineering
will be discussed.
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
79
Consumers, market and sea products
Spanish salt fish market in change
Lindvist K. B.1, Gallart Jornet L.2*
1. Department of Geography, University of Bergen, Bergen, Norway
2. Food Technology Department, Universidad Politécnica de Valencia, Valencia, Spain
S
eafood has become more popular as food, either due to different food diseases or to new organoleptic experiences for former meat consumers. A country like Spain is among the leading countries for fish consumption in the world, also for leading
the way in seafood innovation and for dispersion of seafood to countries with little fish tradition. A traditional fish product in the
Mediterranean countries going far back in time is salt fish production and consumption. Today Spain is a tempting market for
salt fish producers from north European countries. New products are introduced, and new market regulations are developing.
Still traditional products and markets are vigorous at the same time in different Spanish regions. Modern trends in salt fish
consumption are modifying, removing or adapting to the traditional consumption «patterns» for bacalao (dried and salted cod).
Consumer preferences are changing in accordance with development trends linked to demography, technology and production
and consumption regulations. The complex diversity of bacalao preferences within the same country represents a challenge to
the salt fish producers outside Spain.
This work will present and discuss the Spanish markets for bacalao salado as geographic, cultural and technological diversity.
Geographical and cultural aspects will be discussed with reference to consumer traditions and preferences, while the technological diversity of the markets will be presented in connection with changes and development of production technology and
processes. The work will also focus on the reasons for such changes and thus make use of technological studies and cultural,
institutional and spatio-economic theories as analytical principles for analyzing market shifts and innovations in the Spanish
salt fish markets.
80
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
Consumers, market and sea products
Authentication of the European anchovy from the Biscay Bay:
An approach based on the use of molecular techniques
Pardo M. A.­1*, Zarraonaindia I.2, Rendo F.2, Iriondo M.2, Estonba M.2
1. Food Research Division AZTI, Instituto Tecnológico Pesquero y Alimentario Txatxarramendi ugartea z/g, Sukarrieta, Bizkaia E-48395
2. EHU-UPV Zientzia eta Teknologia Fakultatea Genetika laborategia, PO Box 644, Bilbao, Spain 48080
Objective
The European anchovy (Engraulis encrasicolus) is one of the most important and regular fishery in the Biscay Bay. The
consumption of anchovy in Spain is significantly high thus its economic impact is also very important. In fact, there is a notable
commercialization of salt-cured anchovies in oil in Spain, with a consumption of 15 tons/year, as well as in other European
countries like Italy, and France. The anchovy of the Biscay Bay is particularly well appreciated such as semi-preserved product
due to its characteristic taste and tight texture. However, throughout last decades the increasing demand in the consumption of
these products has enlarged the caught of anchovy causing a dangerous over-exploitation of this fishery around Europe and in
particular in the Biscay Bay. This shortage of the European anchovy is causing as well a growing import of species of anchovies
(E. anchoita, E. ringens and E. mordax) from South American countries.
In order to fulfil the labelling requirement of the European Union regulations (EC No 104/2000, it is absolutely necessary to
develop methodologies to assure the traceability system through the whole chain in the anchovy fishery. The principal aim of
this study is the authentication of European anchovy from the Biscay Bay which consists in first place, in the identification of
E. encrasicolus and secondly the identification of geographical origin.
Methodologies
An innovative set of nested primers were designed in order to amplify a diagnosis fragment of 300 bp from mitochondrial cytochrome b gene which allowed to discriminate between E. encrasicolus, E. anchoita, E. ringens and E. mordax. The purified
fragment was directly sequenced and the sequence obtained was subsequently aligned with reference DNA sequences.
On the other hand, more than 400 individuals of anchovies coming from three different stocks of anchovies (Biscay Bay, Lion
Gulf and Cádiz Gulf) were tested with a panel of ten polymorphic microsatellite loci. Eight of these markers were coamplified
in three multiplex PCR reactions, while the other two markers were individually amplified. The fragments were then detected in
three runs on an ABI-PRISM 3100 avant sequencer.
Results
Identification of E. encrasicolus in semi-preserved products by Nested Primer PCR-FINS
Despite of the high DNA degradation level detected in commercial semi-preserved anchovies in oil, the 300 bp fragment was
successfully amplified by Nested Primer PCR in 80 different samples. The analysis by sequencing revealed some fraudulent
substitution of European anchovy by other less valuable species.
Authentication of the geographic origin of the anchovy from the Biscay Bay by using microsatellites
An individual assignment of 69-76% between the different stocks was calculated by using the panel of ten microsatellites loci
developed in this ongoing project. This approach should be complete with other innovative markers obtained after scrutinized
diagnostic nuclear and mitochondrial regions with the final achievement of a 100% of individual assignment.
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
81
Consumers, market and sea products
Differentiation of raw or canned Atlantic herring
(Clupea harengus), sprat (Sprattus sprattus) and
sardine species by PCR-RFLP and PCR-SSCP
Rehbein H.
Federal Research Centre for Nutrition and Food, Departmentof Fish Quality, Palmaille 9, Hamburg, Germany
Objectives
Herring, sprat, sardine and other fish species of the order Clupeiformes are highly appreciated and commercially important in
Europe. PCR-based methods have to be developed for control of declaration of canned products made from these species, as
the products may differ in price, customs tariff and taste.
Methodology
Four PCR systems were used to amplify short sequences (123,150, 233 or 464 base pairs) of the mitochondrial cytochrome b
(1, 2, 3) or tRNAlys/ATPase6/8 gene (4) of DNA isolated from raw or canned muscle of the following species: Atlantic herring
(Clupea harengus), sprat (Sprattus sprattus), sardine (Sardina pilchardus), round sardinella (Sardinella aurita), Pacific sardine
(Sardinops sagax), and anchovy (Engraulis encrasicholus).
The PCR products were characterised by restriction fragment length polymorphism analysis (RFLP of 464 bp amplicon) or
single-strand DNA polymorphism analysis (SSCP of 123, 150 and 233 bp amplicon) using electrophoresis with pre-cast polycrylamide gels and silver staining.
Summary of main results
Amplification of the 123 bp sequence of the cyt b gene, as well as of the150 bp sequence of the tRNAlys/ATPase6/8 gene,
yielded PCR products for all species tested. SSCP analysis gave a specific pattern of DNA single strands in case of each
species.
The 233 bp sequence of the cytochrome b gene was found to be useful for SSCP analysis, too. Differentiation between all
species was achieved, and no intra-specific variation was observed for herring and sardine.
The 464 bp sequence was chosen for RFLP analysis using several restriction enzymes for differentiation between herring, sardine and sprat. By using either Alu I, Nla III or Tru 9I, fragment patterns were obtained by each enzyme allowing differentiation
between the 3 species (Table 1).
Table 1: Fragments obtained for the 464 bp amplicon (length in bp, calculated from position in a 10% polyacrylamide gel)
Species
Alu I
Nla III
Tru 9I
Herring
229, 162
286, 28, 18
177, 159, 76
Sprat
230, 81, 58
374 (uncut)
233, 171
Sardine
241, 168
173, 158
365 (uncut)
Conclusions
Differentiation between sardine-type products of 6 fish species was achieved by 4l PCR-based techniques. Short amplicons
(123, 150 and 233 bp) were found to be useful for SSCP analysis, whereas the 464 bp amplicon was cut by restriction enzymes. Short amplicons were preferred for analysis of canned sardines, and the RFLP of the 464 bp amplicon was successfully
used in case of identifying the species in canned herring.
References
1. Jerome, M. et al. (2003): Direct sequencing method for species identification of canned sardine and sardine-type products.
J. Agric. Food Chem. 51,7326-7332.
2. Hold. G. et al. (2001): Development of a DNA-based method aimed at identifying the fish species present in food products.
J. Agric. Food Chem.49, 1175-1179.
3. Rehbein, H. et al. (1995): Fish species identification in canned tuna by DNA analysis (PCR-SSCP). Infn. Fischwirtsch. 42,
209-212.
4. Burgener, M. (1997): Molecular species differentiation of fish and mammals. Thesis, University of Bern, Switzerland, 52 p.
82
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
Consumers, market and sea products
Traditional fish and fishery products of Turkey
Cakli* S., Cadun A., Dincer T.
Ege University Faculty of Fisheries, Department of Fishery and Fish Processing Technology, 35100 Bornova, Izmir, Turkey
E
xcept of consuming fresh fish, producing traditional seafood especially in some regions is available in Turkey. Some of
traditional seafood are at the same time exported to many countries. The aim of this study is to introduce the special and
traditional producing techniques of commercial fish species in Turkey.
Methodology
Lakerda «Lakerda» is an important utilization technique made from bonito in Turkey. Lakerda is a traditional name of salted
bonito. Lakerda is usually consumed in restaurants and hotels as an appetizer in domestic consumption.
Wax caviar (Mumlu havyar) Serving to consumption of processed fish eggs is quiet limited in Turkey. Fish species evaluated
with eggs are trout and grey mullet. For long storage period of grey mullet eggs, caviar is produced by salting. Caviar processed
like this is named as wax caviar.
Dried and Salted Mackerel Dried and salted mackerel which is called « ciroz » in Turkish which is made of mackerel and chub
mackerel. The delicious and prefers « ciroz » is made from mackerel. The mackerels which take place in black sea and starting
to get fat, they are called as « lipari ». In the past years it was very easy to find dried salted mackerel from fishermen and fish
sellers. But nowadays due to the decrease of catching of mackerel producing dried salted mackerel (ciroz) becomes less and
loose its popularity.
Salted Anchovy (Hamsi tuzlamasý) The fishing of the raw material (Encraulis encrasicholus) in the Black sea which provides
a quality of fish unequalled in terms of size and richness of the meat. The best fishing period ranges in winter. Processing
must occur on the same day of fishing in order to ensure luster using methods which are extremely traditional, totally based on
manual dexterity.
Home salted mackerel (Pickle fish) This meal is made of mackerel (Scomber scomber). Processing step is nearly the same as
the other salted fish food.
Mussel dolma (Midye dolma) Consumption of crustacean is quiet less according to fish consumption in turkey. Mytilus galoprovincialis as known as « kara midye » in Turkey are consumed as mussel dolma or mussel tava. Mussel tava is, frying mussels
covered with flour in a hot oil. Especially it is consumed a lot in the coastal areas in Turkey. Midye dolma done traditionally is
sold in the streets by peddlers. The serves should be made in cool with lemon.
Anchovies packed in salt (Ancuez) Regardless of the type used, preserving anchovies in salt uses a time-honored technique
to deliver that distinctive flavor.
Conclusion Those new seafood choices will be viable alternatives to the consumers of Europe and other countries. And also
one of Salted fish products within the Mediterranean diet. Innovative and traditional products to adapt the new consumer and
the forms in which market supply may be increased with the help of exportation.
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
83
Consumers, market and sea products
Salted fish products within the Mediterranean diet.
Innovative and traditional products to adapt the
new consumer and market trends
Gallart Jornet L., Escriche I., Barat J.M.*, Fito P.
Food Technology Department, Instituto Universitario de Ingeniería de Alimentos para el Desarrollo, Universidad Politécnica de Valencia,
E-46022, Valencia, Spain
T
he main Mediterranean salted fish products: mojama (dried-salted tuna loins), bonito seco (dried salted bonito), garrofeta
(dried salted bonito roe), tonyina de tronc (brined-salted tuna loins), tonyina de sorra (brine-salted tuna flank), sangacho
(brined-salted darkest tuna cuts close to the central spine), bull and budellet (dried salted tuna stomach and intestines), huevas
de atún (dried salted tuna roe), sardinas de bota (salted pressed sardines), melva salada (brine-salted bluefish), caballa oreada
(salted mackerel), bacalao tipo inglés (salted cod, « English type »), capellanes (dried salted blue whitings), musola seca (dried
smoothound shark), pulpo seco (dried octopus), etc. These products, due to tradition and their popularity, may be considered
as an integrated element of our Mediterranean culture. The present outlook for these type of products is however uncertain
and can only be evaluated by comparing former and contemporary times. The salt curing process gives desirable organoleptic
characteristics that a part of the population still appreciates. Nowadays this type of food is considered a « luxury article » and
therefore a « delicatessen » whereas in former times salted fish products were considered as the « food-for-the poor ». At
present times, habits are changing in the society. More women are working, less time is spent for food preparation and convenience foods such as ready-to- use or ready-to-cook products are readily available. Also due to healthier eating, consumers
want less salt in their diet. All these factors have led to a large decrease in the consumption of salted fish products. Despite all,
there is still a « residual demand » for this type of food, not as a « source of protein », but as a « pleasure of eating ». The aim
of this work was to study the « salted fish world » to retrieve part of the patrimony of our culture so that these Mediterranean
products can be reappraised and promoted. A multivariate analysis (PCA) carried out with the compositional data of these products allowed us to classify them regarding the different ways of processing and consumption. Therefore these products were
classified in three groups: lightly salted and dried, salted and dried, and heavily cured salted. Despite being traditional products
they can be promoted following the current trends of « slow food », « good food » and « ready-to- use ». This document is
expected to be used as an « information background », to avoid that our traditions, customs and certain tasks transmitted from
generation for centuries, will disappear into oblivion. It is hoped that this attempt will help somewhat in reconsidering the small
things that constitute our own cultural identity and to update this traditional foodstuff into the new technologies to be introduced
in modern dishes.
84
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
Seafood, marine ingredients
and health
Oral presentations
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
85
Seafood, marine ingredients and health
Keynote lecture
The French network SEApro: a solution to a
better fish wastes management?
Bergé J.-P.*, Barnathan G., Bedouin A., Bourgougnon N., Bourseau P., Fleurence J.,
Fleury Y., Guerard F., Jaouen P., Mireaux M., Picot L., Prost C., Ravallec-Plé R.
Département Sciences et Techniques Alimentaires Marines, Ifremer
B
y its volume of production, the fishing industry occupies a prominent place among the economic activities of the European
community, as reflected by the data presented in the FAO yearbook on the world state of fishing and aquaculture. According
to this report, the weighted discard is estimated at 8%, and the yearly average discards are estimated to be 7.3 million tonnes.
Even if bycatch has declined over the last few years, largely due to more selective fisheries and regulations, there is still great
opportunities to improve their uses and more generally those of the non well exploited biomass (by-products, effluents,…from
fisheries and aquacultural activities). The SEApro network (Sustainable Exploitation of Aquatic PROducts),federating major
actors of the French Atlantic coast, aim to propose new upgrading procedures for the whole biomass and to reduce remaining
wastes. Such global exploitation needs to act on mass production currently in uses such as fishmeal and fish oil for improving
their consumer’s perception (mad cow, dioxin,…) but also to screen for biological activities that could interest cosmetic, nutraceutic and pharmaceutic sectors. For such objectives only soft technologies respecting both product and environment will be
used (enzymatic hydrolysis, membranes technologies,…).
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
87
Seafood, marine ingredients and health
Chub and horse mackerel from the Southern Adriatic
Sea as sources of n-3 PUFA
Testi S.1*, Gatta P.P.1, Bonaldo A.1, Foschi C.2, Fagioli P.1, Fusaroli S.2, Badiani A.1
1. DIMORFIPA Alma Mater Studiorum, University of Bologna, Bologna, Italy
2. Laboratorio di Acquacoltura Alma Mater Studiorum, University of Bologna, Cesenatico (FC), Italy
Objective
To ascertain the extent to which the flesh from chub mackerel (Scomber japonicus) and horse mackerel (Trachurus trachurus)
caught off the Apulia coast (Southern Italy) could contribute to meet human requirements for n-3 polyunsaturated fatty acids
(n-3 PUFA).
Methodology
Two batches per species, 40 fish each, were harvested in the coastal waters of the Gulf of Manfredonia (Southern Adriatic Sea).
Chub mackerel (CMK) were caught in February and in October 2005 (overall average weight ± standard error = 99.0 ± 2.50 g
and 397 ± 4.14 g, respectively), whereas horse mackerel (HMK) were caught in July 2005 and March 2006 (overall average
weight ± s.e. = 305 ± 6.90 g and 297 ± 4.27 g, respectively). Within each batch 20 fish were filleted, the raw skinned fillets of
each fish being paired and individually analysed in duplicate for lipids (chloroform-methanol extraction), and fatty acid composition (% fatty acid methyl esters) and content (mg/100 g edible portion) by capillary gas chromatography. The remaining 20 fish
per batch were thoroughly cooked on an electric open-hearth grill and the flesh from the paired fillets of each fish individually
analysed for the same nutrients.
Summary of the main results
Fall CMK, either raw or cooked, were fattier than winter ones (overall mean (o.m.) = 4.31 vs. 2.02%, P<0.001). Saturated fatty
acid (SFA) percentage was slightly increased by cooking (o.m. 25.81 vs. 26.93%, P<0.01), but it did not seem to be influenced
by catch season. This very effect was the only significant one as to monounsaturated fatty acid (MUFA) and PUFA percentages:
fall CMK were richer in MUFA compared with winter fish (o.m. 20.06 vs. 13.60%, P<0.001), whereas they had a lower content of
PUFA (o.m. 47.10 vs. 53.76%, P<0.001), both of the n-6 (o.m. 5.06 vs. 6.67, P<0.001) and n-3 families (o.m. 40.45 vs. 45.40%,
P<0.001). Being fattier, though, fall CMK had a far higher content of n-3 PUFA. With an average content of 1322 mg/100 g edible portion (range 803 – 1960 mg/100 g), a 100-g serving of grilled flesh was able to cover 82% of daily n-3 PUFA requirement
for an adult male, reaching a maximum of 120% daily requirement for an adult female. Summer HMK, either raw or cooked,
were fattier than winter ones (o.m. 6.23 vs. 4.55%, P<0.001). SFA percentage was slightly decreased by cooking (o.m. 29.16
vs. 27.46%, P<0.001), catch season still having no significant effect on this group of fatty acids as already observed for CMK.
Other groups of fatty acids, namely MUFA, n-3 PUFA and PUFA on the whole, behaved quite differently in this species, being
affected by both state (raw-cooked) and catch season. The highest n-3 PUFA content was found in the grilled flesh of summer
HMK, with an average content of 1936 mg/100 g edible portion (range 1328 - 2973 mg/100 g), high enough to exceed by far
the daily requirements of an adult male.
Acknowledgements
The full cooperation of the «Consorzio per il Mercato Ittico all’Ingrosso di Manfredonia» (Manfredonia, Italy) is gratefully acknowledged.
88
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
Seafood, marine ingredients and health
Cholesterol and fatty acid profile of some fish
species caught off North Atlantic Ocean, Portugal
Nunes M.L.1*, Afonso C. 1,2, Leitão M.1, Bandarra N.M.1,
Lourenço H.M.1, Martins M.F.1, Cas M.
1. INIAP-IPIMAR, Av. Brasília, 1449-006, Lisbon, Portugal
2. Faculdade de Farmácia da Universidade de Lisboa, Av. das Forças Armadas, 1649-019, Lisboa, Portugal
T
he low content in cholesterol and high level of polyunsaturated fatty acids are characteristics of marine lipids contributing to
important benefits in human health. The main objective of this work was to determine such levels in some species consumed in Portugal in a way to contribute to a better knowledge of their nutritional value. Species studied were: angler and blackbellied angler (Lophius piscatorius and budegassa, respectively), black scabbardfish (Aphanopus carbo), blackbelly rosefish
(Helicolenus dactylopterus) and in megrim and fourspotted megrim (Lepidorhombus whiffiagonis and boscii, respectively).
In this experiment 10 individuals with commercial size from each species were used. All samples were gutted, filleted and
minced before analyses.
Determination of cholesterol and fatty acids profile were done by gas chromatography (GC).
The highest cholesterol content was around 30 mg/100 g edible part and attained in megrim and fourspotted megrim. Concerning the fatty acid profile, angler and black-bellied angler and blackbelly rosefish species showed polyunsaturated as prominent
group (43.1 and 33.6%, respectively), followed by saturated (29.9 and 28.6, respectively) and monounsaturated (21.2 and
33.3%, respectively). In opposite, black scabbardfish and megrim and fourspotted megrim species presented high levels of
monounsaturated (54.1 and 36.8%, respectively) followed by the polyunsaturated (18.0 and 31.2%, respectively) and the saturated (19.6 and 29.1%, respectively). The maximum level of docosahexaenoic acid (DHA) (150.8 mg/100 g), eicosapentaenoic
acid (EPA) (44.4 mg/100 g) and a ratio n3/n6 of 53.3 were found in megrim and fourspotted megrim species. The high level of
monounsaturated fatty acids registered in black scabbardfish is probably consequence of habitat (deep-water).
In conclusion, this work allow to confirm that although the low fat content characteristic of these species, the levels of EPA and
DHA make them good contributors for the minimum daily dietaries intakes.
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
89
Seafood, marine ingredients and health
Multielemental analysis of raw and cooked
flesh from two underutilised fish species
Gatta P.P.1, Testi S.1*, Bonaldo A.1, Silvi M.2, Ghidini S.3, Badiani A.1
1. DIMORFIPA, Alma Mater Studiorum, University of Bologna Bologna, Italy
2. Laboratorio di Acquacoltura, Alma Mater Studiorum, University of Bologna, Cesenatico (FC), Italy
3. Dip. Produzioni Animali Biotecnologie Veterinarie Qualità e Sicurezza degli Alimenti University of Parma, Parma, Italy
Objective
To determine macro and micro element contents of the flesh, both raw and cooked, from chub mackerel (Scomber japonicus)
and horse mackerel (Trachurus trachurus), two underutilised finfish species frequently caught in the waters of the Gulf of Manfredonia (Apulia, Italy).
Methodology
Two batches per species were obtained, dressed, and cooked as described by Testi et al. (same proceedings). After freezedrying, 0.5 g of each homogenised sample, made up of paired skinned fillets either raw or cooked, were mineralised in duplicate in a microwave system. The macro (sodium, Na; potassium, K; calcium, Ca, magnesium, Mg; phosphorus, P) and micro
(iron, Fe; zinc, Zn; copper, Cu; manganese, Mn; selenium, Se) element contents of the samples were determined by inductively
coupled plasma optical emission spectrometry (ICP-OES). The quality of the analytical results was controlled by repeatedly
analysing for relevant elements two certified reference materials, NRCC- DORM2 (dogfish muscle) and BCR-422 (cod muscle),
during the 14-month research period.
Summary of the main results
The elemental content of the flesh from chub mackerel (CMK) was almost always affected by catch season, the only exception
being Mn and Se. Fall CMK flesh was significantly richer in K, Mg, P, Fe, Zn, and Cu. Grilling induced a statistical significant
decrease in Na, K, and Mg contents, while having a significant concentration effect upon Zn and Se. CMK cooked flesh, whichever season, was quite a remarkable source of Se, a 100g serving being able to cover 133% of the requirements of an adult,
both sexes. A serving of fall grilled CMK was also an interesting source of P and K (able to cover on average 43 and 10% of an
adult daily requirements, both sexes, respectively), and of Zn and Fe (a serving being able to cover 19 and 17% of the requirements of an adult female and male, respectively).
Catch season affected significantly the content of several elements in the flesh of horse mackerel (HMK): Na, K, Mg, and Fe
levels were higher in wintertime, whereas Mn and Se contents increased in summer. Grilling caused a significant increase in
the concentration of Na, K, P, Mg, Fe, Cu, and Se, while Zn and Mn decreased. The grilled flesh from HMK, whichever season,
was quite a valuable source of P (a standard serving being able to cover around 37% of the daily requirements of an adult, both
sexes) and an interesting source of Zn for adult females (around 10% of their daily needs). Summer cooked HMK flesh could
boast so high a Se content that a standard serving would be able to cover 158% of the daily requirements of an adult. The
cooked flesh from winter HMK, on the other hand, was both an important Fe source to adult males (22% of daily requirements)
and an interesting source of K to both sexes (9% of daily requirements).
Acknowledgements
The full cooperation of the « Consorzio per il Mercato Ittico all’Ingrosso di Manfredonia » (Manfredonia, ITALY) is gratefully
acknowledged.
90
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
Seafood, marine ingredients and health
Nutritional composition and some
contaminants metals in cephalopods
Lourenço H.M.1, Anacleto P.1, Afonso C.1, Martins M.F.1, Lino A.R.2, Nunes M.L.2*
1. INIAP-IPIMAR, Av. Brasília, 1449-006, Lisbon, Portugal
2. Sciences College of Lisbon University, Edifício C8, Campo Grande, Lisbon, Portugal
C
ephalopods are one the most important group species captured in Portugal (especially common octopus), and they are
very appreciated in Portugal. They have high protein content and they are a excellent source of some essential elements
but, due to their morphological and biological characteristics associated to the habitat these species accumulate some contaminant metals in their tissues. Thus, chemical composition, some essential and contaminant metals were evaluated in common
octopus (Octopus vulgaris), squid (Loligo vulgaris) and common cuttlefish (Sepia officinalis), collected in 2004-2005 in continental Portuguese coast.
Chemical composition was done according AOAC procedures and essential and contaminant metals were determined by atomic absorption spectrometry.
The results obtained for chemical composition showed a high protein level for the three species, between 13.6% (octopus) and
18,5% (cuttlefish) but a low fat content (around 1.0%). In what concerns mineral concentration, octopus samples presented the
higher level, 2.4%. All studied samples exhibited interesting mean levels of zinc (about 17 mg/kg wet weight), cupper (about
4 mg/kg wet weight) and magnesium (between 465 and 940 mg/kg weight). The mean total mercury concentration was about
0.12 mg/kg wet weight, with the highest content found in common cuttlefish (0.36 mg/kg wet weight). However, such values
did not exceed the proposed limit for cephalopods by EU (0.5 mg/kg). All analyzed samples showed lead and cadmium levels
lower than the indicated limits (1.0 mg/kg).
In conclusion, this study indicates that cephalopods caught off in Portugal are a good source of protein, minerals and the levels
of heavy metals are significantly lower than the limit values proposed by UE.
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
91
Seafood, marine ingredients and health
Production of omega-3 polyunsaturated fatty acid
concentrate from sardine oil using immobilized lipase
Okada T., Morrissey M.*
Oregon State University, Seafood laboratory, 2001 Marine Dr., Rm. 253 Astoria, Oregon, USA, 97103
A
study was conducted to develop an immobilized-enzyme system to entrap lipase in chitosan-alginate-CaCl2 beads for the
purpose of concentrating n-3 polyunsaturated fatty acids (n-3 PUFAs) from sardine oil. The objectives were to determine
the characteristics of the system, hydrolytic activity and efficiency for n-3 PUFA concentration compared with a free lipase system. Lipase was immobilized by an ionotropic gelatin method, and beads composed of alginate- chitosan, alginate-CaCl2, and
alginate-chitosan-CaCl2 were analyzed for characteristics including mechanical strength and morphology. Immobilized lipase
beads composed of alginate-chitosan-CaCl2 were analyzed for lipase loading efficiency, optimum pH and temperature and
fatty acid profiles following hydrolysis. Lipase-immobilized beads prepared with alginate-chitosan-CaCl2 showed the highest
mechanical strength. Scanning electron microscopy analysis revealed that lipase had a strong influence on bead structure.
Optimum pH of immobilized lipase shifted from 7.0 to pH 6.0 and immobilized lipase showed higher stability against pH and
temperature changes. Original sardine oil contained 38.13% n-3 polysunsaturated fatty acids (PUFAs) (25.20% 20:5n3 and
7.2% 22:6n3) and the concentration was significantly increased to 65.32% (40.24% 20:5n3 and 15.46% 22:6n3) with free lipase
and to 64.77% (39.64% 20:5n3 and 15.33% 22:6n3) with immobilized lipase after 90 min of repeated hydrolysis. Fatty acid of
the free fatty acid (FFA) fraction of hydrolyzed oil showed that lipase preferably hydrolyzed 16:0, 16:1n7 and 18:0 accounting
for 76.56% and 69.51% of total FFAs (after first and second hydrolysis, respectively). Among different lipid fractions, the diglyceride fraction contained the highest n-3 PUFAs. This study shows that use of immobilized lipase systems for increasing n-3
PUFA concentration in sardine oil provides new process opportunities for the industry.
92
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
Seafood, marine ingredients and health
Sea bass healthy eating quality for consumers needs: in vivo
fillet lipid quantity/quality estimation and intake
effect on circulating markers of atherosclerosis
Poli B.M.1*, Abbate R.2, Parisi G.1, Gori A. M.2, Sofi F.2, Mannini L.2, Giorgi G.1
1. Dept. Scienze Zootecniche, Via delle Cascine 5, 50144, Firenze, Italy
2. Dept. Area Critica Medico-Chirurgica, Florence University, Firenze, Italy
S
ea bass is one of the most consumed reared species in Italy, where it is produced, but also imported, in large quantity. Sea
bass fillet and lipid quantity/quality can be adjusted to maximise the healthy eating impact of their intake, generally able to
supply high n-3 PUFA, EPA and DHA levels. Together with the principal factor, i.e. a correct diet to the fish, other tools (such
as a more strictly monitoring of fillet and its lipid/fatty acid quantity during rearing) and the evaluation of healthy eating traits
of the final product, could contribute to sea bass gradual tailoring to the consumers needs. The aim of research was 1) to get
to a reliable estimates of sea bass flesh lipid/fatty acid weight through simple, not destructive morphometric measures to be
monitored during rearing and 2) to test the fillets healthy eating quality through an intervention study to evaluate the influence
of sea bass fillets intake on biomarkers related to the to atherosclerotic/thrombogenic processes.
Fillet lipid quantity/quality estimation.
The complex of data, derived from more than 700 Orbetello (Italy) farmed sea basses (250-1200g b.w. range) indicated
the possibility to estimate with a good reliability both the weight of fillets (by body weight and max thickness measures:
R2=0.96, rsd=±20.55 g) and the intramuscular lipid content (by b.w., total length, max thickness and condition factor: R2= 0.69,
rsd=±3.3 g). The n-3 PUFA and EPA contents in flesh, determined on a representative sub sample (n. 120), were also estimated (by condition factor and max girth: R2= 0.32, rsd=±0.42 g and R2= 0.38, rsd=±0.13 g, respectively).
Intake effect on circulating markers of atherosclerosis.
The healthy eating quality evaluation of fish muscle was estimated by changes in blood parameters of 7 dyslipidemic subjects
(4 females and 3 males; 53.1 years mean age), evaluated after a 10 week-long dietary intervention program of three times a
week comsumption of skinned fillets. The blood parameters measured before and after fish intake were: a) erythrocytes fatty
acid composition, b) lipid profile (total cholesterol, HDL-cholesterol, LDL-cholesterol and triglycerides), c) inflammatory markers
(interleukin-6 and interleukin-8), d) haemorheological profile [whole blood viscosity (WBV), plasma viscosity, erythrocyte filtration rate], and platelet function [platelet aggregation and platelet function on whole blood (PFA)]. The weekly intake of 800 g of
muscle, containing 66 g of lipid, 12.3 g of EPA+DHA and 16.8 g of MUFA was followed by an increase in erythrocytes n-3 PUFA
(4.11 vs 10.48%; P<0.05) and by a decreasing trend of triglycerides (170.1 vs 143.8 mg/dL), interleukin-6 and interleukin-8
(1.9 vs 1.6 pg/mL; 17.4 vs 12.2 pg/mL), and haemorheological parameters (WBV11.040 sec-1: 8.7 vs 7.8; WBV20.400 sec-1:
6.4 vs 4.3; WBV94.500 sec-1: 4.5 vs 4.3) (P<0.04). The experimented weekly intake of sea bass fillets seemed to set up favourable biochemical changes in dyslipidemic subjects, with regard to lower circulating levels of markers of atherosclerosis, such
as lipid parameters, inflammatory markers and haemorheological profile.
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
93
Seafood, marine ingredients and health
Study of live and frozen Anisakis
larvae treated with pepsin
Tejada M.1*, Solas M.T.2, Navas A.3, Mendizábal A.4
1. Instituto del Frío (IF) Consejo, Superior de Investigaciones Científicas (CSIC)
2. Departamento de Biología Celular, Facultad de Biología, UCM
3. Museo Nacional de Ciencias Naturales (MNCN), Consejo Superior de Investigaciones Científicas (CSIC)
4. Ayuntamiento de Madrid, Instituto de Salud Pública, Departamento de Seguridad Alimentaria Unidad Técnica MERCAMADRID
I
ngestion of fish parasitized with Anisakis larvae (L3) can cause in humans infestation, which occurs when the larva is eaten
live, and allergy of varying intensity produced by different allergens secreted by the larvae and excreted to the host, some of
which have been shown to be high-temperature, acid and pepsin resistant. In a previous work we have detected changes in
the cuticle of the parasite due to different technological and food processing treatment that modify the resistance to the pepsin
and acidic conditions.
The aim of this work is to study the effect of a simulated digestion with pepsin in a preliminary approach. Live and frozen Anisakis simplex larvae and artificially infested fish muscle were stored chilled or frozen and later were subjected to the simulation of
a gastric digestion using pepsin solution in standard conditions. The movement, mortality of the larvae and excretion of protein
to the media in the different treatments was studied. Scanning electron microscopy (SEM) of the parasites showed disruption
in the cuticle with emerging of internal tissue in different degrees that were determined by the time of digestion (4 - 24 h) and
the treatment given to the fish and the parasites (chilled or frozen). Transmission electron microscopy (TEM) showed disrupted
areas in the fish tissue and granules in the contact zones between the parasites ant the fish muscle that were probably excreted by the parasite to the surrounding tissue. This could cause a different allergic response when fish infested with Anisakis is
consumed. Work is in progress to evaluate the nature of the granules and the protease activity of the parasites.
This work has been financed by Projects AGL2005-05699-CO2-01 ALI (ANITRAT) and PIE 2004 7 0E 160.
94
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
Seafood, marine ingredients and health
Towards the development of marine bio-ingredients
with antioxidant properties: a case study
Guérard F.1*, Chabeaud A.1,2, Laroque D.1, Denes A.1, Vandanjon L.2,
Bourseau P.2, Jaouen P.3, Thorkelsson G.4
1. University of Bretagne Occidentale, ANTiOX Laboratory
2. University of Bretagne Sud, LETEE Laboratory EA3373 Lorient, France
3. University of Nantes, GEPEA UMR-CNRS 6144 Saint-Nazaire, France
4. Gudjon Thorkelsson Icelandic Fisheries Laboratories, Iceland
I
n a global context of marine biological resource overexploitation, a better upgrading of fish and shellfish biomass is a challenge for the 21st century. One of the main and promising issues will be the production of marine bio-ingredients using enzymatic hydrolysis. The keysteps in the production of enzymatic hydrolysates with antioxidant properties will include the following
points:
-enzymatic hydrolysis of the substrate(s): importance of pH and temperature control;
-a useful tool for checking the reproducibility of the process: the SEC-FPLC with an appropriate fractionation range.
-requirement to use several in vitro tests in order to evaluate the antioxidant capacity of hydrolysates. These assays
may be associated with cell cultures and/or in vivo assays according to the targeted applications.
-fractionation using ultrafiltration or nanofiltration
All these points will be illustrated from a practical point of view with somecase studies.
This work was performed within the Integrated research Project SEAFOODPlus, Contract N° FOOD-CT-2004-506359. The
partial financing of this work by the European Union is gratefully acknowledged.
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
95
Seafood, marine ingredients and health
Improving functional properties of tuna
by-products by non-enzymatic glycosylation
Arboleya J.-C.1*, Moreno J.2, Sanmartín E.1, Wilde P.J.3
1. Azti-Tecnalia, Txatxarramendi ugartea z/g 48395 Sukarrieta Bizkaia, Spain
2. Instituto de Fermentaciones Industriales (CSIC), Juan de la Cierva 3, 28006, Madrid, Spain
3. Institute of Food Research Norwich Research Park, Norwich, United Kingdom NR4 7UA
F
ishery processing discards provide sources of raw material for preparation of protein food and feed ingredients. Optimal
utilisation of fishery by-products is becoming increasingly important in order to improve use of food resources for human
consumption. The industrial applications of food proteins are limited because proteins are generally unstable. Glycation of
proteins is expected to overcome their instability to heating and to further improve the functional properties. Some investigations have reported that non-enzymatic glycosylation can be an efficient method to generate new modified proteins with great
industrial and technological interest.
The aim of this research was to obtain a protein concentrate with novel functionality via the Maillard reaction from fish waste
which is used currently for animal feed. This study is focused on the improvement of solubility in this fish waste and the interfacial properties of either a native tuna protein concentrate (TPC) in presence of carbohydrates or TPC conjugated with glucose
through Maillard reaction under controlled conditions. The surface rheology, surface tension and foam stability of the mixed
protein:carbohydrate system and the glyco-conjugates were studied to reveal the mechanism and consequences of this chemical modification.
Conjugation with glucose or dextran greatly improved the solubility of tuna by-products. The effect of degree of glycation under
different conditions was related to the level of foaming capacity on these conjugates. The results revealed that the surface behaviour was influenced by the carbohydrate size and the rate of glycosylation. Consequently, this change in surface properties
was reflected in the foam stability behaviour. The foaming properties of TPC were effectively improved with an increase in the
amount of conjugating glucose and dextran. The results are discussed in terms of the molecular structure and interfacial properties of the different components, together with the influence of the physical properties of the system on foam stabilisation.
The results of potential effects on functionality enhancement are as yet unknown and the production of non-enzymatic glycated
proteins with new or enhanced functional properties could contribute to greatly expand the applications of fishery by-products
in food processing.
96
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
Seafood, marine ingredients and health
Phenolic content and antioxidant capacity of
extracts from sea cucumber, Cucumaria frondosa
Mamelona J.1, Pelletier É.1*, Girard-Lalancette K.2,
Legault J.2, Karboune S.3, Kermasha S.3
1. Institut des sciences de la mer, Université du Québec à Rimouski, 310, allée des Ursulines, Rimouski (Qc) Canada G5L 3A1
2. Université du Québec à Chicoutimi, Ville Saguenay (Qc) Canada
3. McGill University, Montreal (Qc) Canada
I
n the last three years, our group has been active in extraction and characterization of active fractions from echinoderms, including green sea urchin, various seastar species and sea cucumber. The antioxidant activity (oxygen radical absorbance capacity, ORAC) and total phenols and flavonoids were determined in extracts from digestive tract, gonads, muscles and respiratory
apparatus of sea cucumber, Cucumaria frondosa, collected in St. Lawrence Estuary by scuba diving. Total phenols varied from
22.5 to 236.0 mg of gallic acid equivalent/100 g d.w., and flavonoids from 2.9 to 59.8 mg of rutin equivalent/100 g. ORAC values
ranged from 140 to 800 µmol of Trolox equivalent/g d.w. Best antioxidant potencies were observed in organic extracts from
digestive tract, and in acetonitrile-rich fractions obtained from muscles, gonads and respiratory apparatus. The weakest antioxidant potencies were observed with water extracts from digestive tract and respiratory apparatus, and with water-rich fractions
from gonads and muscles. A significant correlation was observed between ORAC values and total phenol content found in
extracts and fractions of gonads and muscles, but ORAC and phenols were not correlated in digestive tract and respiratory
apparatus extracts. ORAC values were significantly correlated (p< 0.05) to total flavonoids in all extracts. Successive eluates
obtained from solid-phase extraction of water-rich fractions using C18 cartridge showed ORAC values (105 - 500 µmol of TE/g)
reaching up to 2.3 times the potency of their parent fractions. Flavonoids are suggested to be mainly responsible for observed
activities. The edible part of C. frondosa (muscles) can provide to consumers an appropriate anti-peroxyl radical protection,
but by-products including gonads, digestive tract and respiratory apparatus also showed the moderate antioxidant potential of
C. frondosa and a possible valorization of these tissues as an additional source of antioxidants for human diet.
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
97
Seafood, marine ingredients and health
Role of herring mince, herring oil and herring
« press juice » in counteracting negative health effects
in rats caused by a cafeteria-style Western diet
Undeland, I.1*, Sandberg, A.-S.1, Sannaveerappa, T.1, Lindquist, H.1,
Larsson, B.M.2, Lönn, M.2, Holmäng, A.2
1. Chalmers University of Technology, Department of Chemistry and Bioscience
2. Sahlgrens Academy Department of Neuroscience and Physiology, Göteborg, Sweden
T
he combination of a western diet and reduced physical activity has lead to a rapid increase in the metabolic syndrome
among children and young adults. The metabolic syndrome includes a raised risk for diabetes type II, high blood pressure,
high levels of blood lipids and obesity, ultimately leading to an increase in cardiovascular disease (CVD). Numerous scientific
investigations have indicated that a regular intake of fish can reduce the risk for CVD by affecting various CVD risk markers.
However, no dietary studies so far have searched beyond the n-3 fatty acids in order to explain the beneficial effects from
a fish containing diet. The aim of this study was to investigate whether a daily intake of oven-baked herring mince; isolated
herring-derived oil or herring-derived «press juice» (the aqueous fraction of the muscle) could reverse negative health effects
caused by a cafeteria-style western diet (cwd) consisting of cookies and chicken mince. The study comprised 6 ´ 16 male Wistar rats which for 8 weeks were given: (i) regular rat chow (controls), (ii) cwd, (iii) cookies + herring mince, (iv) cwd + herring
oil, (v) cvd + herring press juice and (vi) cvd + protein- free herring press juice, respectively. The parameters measured were:
atherogenic index (total cholesterol-HDL- cholesterol/HDL-cholesterol), blood pressure, insulin sensitivity, adipose tissue distribution (% inguinal, mesenteric, retroperitoneal, and parametrial (females)/ epididymal (males) adipose tissue), fat tissue mass,
lean tissue mass, total mass (BMC + lean mass + fat mass),% fat (fat mass/total mass) and urinary oxidation products (isoprostanes). Results obtained so far showed that a cwd-induced increase in atherogenic index was slightly reduced by herring
press juice, and fully normalized by herring mince and herring oil. Herring oil also reversed a reduced insulin sensitivity caused
by the cwd.
98
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
Seafood, marine ingredients and health
Risks and benefits of seafood consumption: can
they be balanced in a meaningful way ?
Valdimarsson G.*, Elvevoll E.
Institute of Marine Biotechnology, University of Tromsø, Tromsø, Norway
T
he paradigm of food safety has progressed from food inspection to food control to risk management. That is an acknowledgement that, by and large, food cannot be made risk free for all people at all times.
The scientific risk approach to food safety was formally embraced in the Sanitary and Phytosanitary Agreement (SPS Agreement) of the World Trade Organization (WTO) in 1995. As a consequence work is being undertaking worldwide measuring
the potential risk associated with consumption of different foods. At the same time a more holistic view on foods is emerging
as they are increasingly being viewed in light of their overall wholesomeness. This implies evaluating not only the harmful
elements of foods but also the beneficial ones i.e. balancing the risks and the benefits from consuming a particular food. The
Codex Commission has recently requested the Food and Agriculture Organization (FAO) and the World Health Organization
(WHO) to consider convening an expert consultation on the health risks associated with the consumption of fish and other
seafood as well as the health benefits. The terms of reference for this work are: (1) Assessment of the health risks associated
with the consumption of fish and other seafood (2) Assessment of the health benefits of fish and other seafood consumption
and (3) Comparison of the health risks and health benefits of fish and other seafood consumption. Regarding this last point
the Commission requests FAO/WHO to develop a methodology and identify the data necessary for carrying out quantitative
assessments of risks and benefits related to fish and other seafood consumption.
It is recognized at the outset that this is an extremely complex issue, which the paper will discuss with a view to possible approaches as well as the implications.
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
99
Seafood, marine ingredients and health
Bioactive properties of protein hydrolysates products
from Channel catfish protein isolate
Kristinsson H.G.*, Theodore A. E., Petty H. T., Raghavan S.
Laboratory of Aquatic Food, Biomolecular Research Aquatic Food Products Program
Department of Food Science and Human Nutrition, University of Florida, Gainesville, Florida, USA, 32608
F
ish protein hydrolysates have been the focus of investigation for decades, mainly for their use as food ingredients but now
recently as ingredients with certain bioactive properties. Hydrolysates are typically produced from byproducts of varying
composition and quality and as a result the final hydrolysate composition can be inconsistent and they can also contain impurities which can compromise their quality. Recently a novel technique was developed where proteins are extracted from
byproducts using high pH followed by a low pH precipitation of the proteins. The final product is a very consistent high protein
material, mainly consisting of water and concentrated myofibrillar proteins. This new technology produces an economical and
very clean substrate for enzymatic hydrolysis to produce high quality fish protein hydrolysates.
The objective of our work was to produce hydrolysates from catfish protein isolates and investigate how their bioactive properties related to degree of hydrolysis.
Catfish protein isolates were made by first homogenizing catfish muscle and then solubilizing its protein at pH 11.0 followed
by centrifugation to remove insoluble materials. The soluble protein fraction was collected and adjusted to pH 5.5 followed by
centrifugation to recover the proteins. The catfish protein isolate was diluted to 3% protein, equilibrated to 22 °C and pH 7.5
and the enzyme mixture Protamex® added. The hydrolysis reaction was monitored using the pH- stat method and then terminated by heating the mixture to 90 °C for 10 min, once the target degree of hydrolysis (%DH) was reached (5%, 15% and 30%
DH). The hydrolysates were then collected and analyzed with SDS-PAGE. Antioxidative properties of the hydrolysates were
investigated using various methods: (a) DPPH radical scavenging activity, (b) Hydroperoxide reduction, (c) Metal ion chelating
activity, (d) Reducing power, (e) Oxygen radical absorbance capacity (ORAC), and (f) Lipid oxidation in hemoglobin-washed
fish muscle system. The ability of the hydrolysates to inhibit the Angiotensin I Converting Enzyme (ACE), which is important in
blood pressure regulation, was also investigated.
Increased %DH produced progressively smaller peptides. Results showed that the hydrolysates had very strong radical scavenging activity which increased as %DH and thus peptides became smaller. The ORAC method also demonstrated that
« overall antioxidative capacity » increased significantly as %DH increased. Metal chelation activity of the hydrolysates was
also increased significantly as %DH increased, while the reverse trend was seen for their reducing power. Studies in a washed
fish muscle substrate with hemoglobin as a catalyst also demonstrated that the hydrolysates possessed good antioxidative
properties. In addition to antioxidative effects, the hydrolysates demonstrated strong ACE inhibition activity, as they were able
to inhibit 70-90.6% of the enzymes activity at only 0.15% protein concentration.
These results demonstrate that hydrolysates made from catfish protein isolates have good bioactivities, both in terms of antioxidative activities and ability to perhaps reduce hypertension, and therefore could find potential use as functional food ingredients. The results furthermore demonstrated that peptide makeup is important for the activity of the hydrolysates.
100
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
Seafood, marine ingredients and health
Chitosan-based delivery of protamine to food
systems through nano-encapsulation
Doucet E.*, Gill T.A.
Department of Process Engineering and Applied Science, Dalhousie University
F
ood preservation is a continual challenge in maintaining food safety. Consumer outlooks are ever changing and the need
to limit chemical food preservatives and replace them with « natural » alternatives is increasing. Research in this area is
currently focussed on exploring alternatives to chemical preservatives. Chitosan (CS), a marine-based cationic polysaccharide
abundant in nature, is formed from the depolymerisation of chitin found in crustaceans. CS is water- soluble at acidic pH and
has been shown to have antimicrobial activity. It can cross-link to form CS gels and packaging films and has been used for
microencapsulation. However the production of 50-200 nm CS nanoparticles is a recent development currently being tested
for drug delivery.
Protamine (Ptm) is a cationic antimicrobial peptide (CAP) derived from the milt of pelagic fish such as herring and salmon and has
been shown to have broad range antibacterial activity toward a number of Gram-positive and Gram-negative cells. Prior work with
protamine has shown antimicrobial activity in real food systems is often suppressed by its non-specific binding to anionic components
present and therefore strategies are being sought to protect Ptm from non-specific binding.
The objective of this study was to incorporate Ptm into CS nanoparticles and determine the release properties and antimicrobial delivery for potential use as a food additive. Nanoparticles were formed by the ionic interaction between CS and Ptm followed by of the
cross-linking of the complex with tripolyphosphate (TPP). Various concentrations of Ptm were used to determine the binding capacity
to chitosan and free protamine in solution was determined using a Coomassie Blue G Assay. Release studies were performed to
determine the rate of protamine release into solution and its antimicrobial efficacy determined in fresh milk inoculated with Listeria
monocytogenes (LM). Scanning electron microscopy (SEM) was used to examine the morphological characteristics of nanoparticles
prepared under a number of conditions. The paper describes the comparison of Ptm in free solution as compared to its antimicrobial
action in encapsulated form.
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
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October 29th - November 1st 2006, Québec City, Québec, Canada
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Seafood, marine ingredients and health
Stypopodium zonale: a marine algae with anti-inflammatory,
analgesic and anti-oxidant effetcs
Llanio, M.1*., Fernández, M.D.1, Cabrera, B.1, Bermejo, P.2,
Abad, M.J.2, Payá, M.3, Alcaraz M.J.3
1. Marine Bioproducts, Center Havana, Cuba
2. Dpto. of Pharmacology Faculty of Pharmacy, University Complutense of Madrid, Madrid, Spain
3. Dpto. of Pharmacology Faculty of Pharmacy, University of Valencia, Valencia, Spain
F
rom the marine organisms have been obtained compounds with anti-inflammatory effects from sponges, coelenterates
and algae. A representative compound of the algae, due to its great number of properties, is the epitaondiol that inhibits
phospholipase A2 enzyme (PLA2) and the formation and/or liberation of prostaglandins and leucotriens. Another anti- inflammatory compound also isolated from marine algae it is the pacifenol that, besides the above mentioned, inhibits the formation
of reactive species of oxygen. (Alcaraz and Payá, 1994)
Keeping in mind that previously pointed out, we realized the study of an extract obtained from Stypopodium zonale, present in
the Cuban coasts, with the aim to know if it presented anti-inflammatory, analgesic and antioxidant properties and the possible
mechanisms of action of these effects. For these we used different in vivo tests like croton oil and arachidonic acid mouse ear
oedema and writhing induced by acetic acid, as well as in vitro inhibition test like phospholipase A2 (PLA2), ciclooxigenase
(COX), lipid peroxidation (TBA) and superoxide dismutase activity (SOD). Also was carried out an assay to evaluate the toxicity.
As a result of the realized tests was proven that the extract inhibits the mouse ear oedema induced by both compounds, the
PLA2 of bee poison and human recombinate source, the writhing induced by acetic acid, the lipoperoxidation, and has mimetic
SOD activity. It doesn’t present toxicity in the realized assay.
We can conclude that the Stypopodium zonale extract presents anti-inflammatory, analgesic and antioxidant properties.
102
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
Seafood, marine ingredients and health
Erythrocyte membrane fatty acid incorporation as
a marker of fish diet in young overweight europeans
Bandarra, N.M.1*, Monteiro, M.1, Parreira, R.1, Paulo, M.C.1, Andrade, A.M.1,
Gisladóttir, E.2, Martinez, J.A.3, Parra, L.3, Kiely, M.4, Thorsdóttir, I.2
1. Departamento de Inovação Tecnológica e Valorização dos Produtos da Pesca, INIAP/IPIMAR
2. Unit for Nutrition Research Landspitali, University Hospital, Iceland
3. The Department of Physiology and Nutrition, University of Navarra, Navarra, Spain
4. Department of Food and Nutritional Sciences, University College Cork, Cork, Ireland
Objective
Evaluate the effect of controlled diets with a caloric restriction of 30%, supplemented with lean (cod) and fatty fish (salmon) in
erythrocyte membrane fatty acids and to compare with the results obtained with a standard diet without fish.
Methodology
Recruitment of healthy volunteers from Iceland (87), Ireland (43) and Spain (78) was done following inclusion criteria: age
between 20 and 40 years, apparently healthy, body mass index between 28-32 kg/m2. Some exclusion criteria were the ingestion in the last 2 months of calcium, Vitamin D, omega-3, anti-inflammatory drugs, insulin or anti-hypertensive. A two day food
frequency questionnaire was filled by each volunteer to access nutrition and lifestyle habits. Total blood was fractionated and
erythrocytes were freeze-dried for fatty acid analysis. A selective basic transesterification during 1 hour was followed in order to
derivatize only the phospholipid fraction. The fatty acid profile was determined by gas chromatograph fitted with an ionisation
detector. Fatty acid methyl esters were identified by comparison of their retention time with those of chromatographic standards. Statisticall treatment of data was performed using Nonparametrical analysis with Statistica 6.0 software, by t equivalent
matched pairs test Wilcoxon, (p<0.05).
Summary of the main results
Salmon diet was responsible for a statistical significant increase of total n-3 fatty acids (p<0.001), particularly EPA (Eicosapentaenoic acid, p<0.001) and DHA (Docosahexaenoic acid, p<0.001). On the other hand total total n-6 fatty acids decreased
significantly (p<0.001) and AA (Arachidonic acid, p=0.021) was the main responsible for this result. Cod diet enhanced significantly DHA level (p<0.001), showing that this fatty acid is a good marker of fish consumption even fish species with a low fat
content. A diet without fish incorporation for two months promoted a significant increase of AA (p<0.001) and a decline of total
n-3 fatty acids (p<0.001).
Conclusion
These results suggest that fish consumption has beneficial effects on the erythrocyte membrane fatty acid composition and
hence can have an important role in the prevalence rates of cardiovascular disease in these countries.
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
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New concepts to minimize
seafood associated risks
Oral presentations
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
105
New concepts to minimize seafood associated risks
Keynote lecture
What can barcoding do
for fishery technologists?
Dufresne F.
Département de biologie, Université du Québec à Rimouski
D
NA barcoding is a technique for characterizing species using a short DNA sequence from a standard and agreed-upon position in the genome. The cytochrome c oxidase subunit 1 mitochondrial region (COI) is emerging as the standard barcode
region for species identification. The gene portion utilized for barcoding is 648 nucleotide base pairs long and it shows high
interspecific but low intraspecific divergences. Recent studies have shown that this gene is very powerful in discriminating species and phylogeographic groups within species. As a uniform method for species identification, DNA barcoding has appealing
applications in fisheries as it offers a simple, rapid and inexpensive means of identifying not only whole animals, but fragments,
eggs and larvae. Because of complications due to genomic fluidity, the CO1 gene is not used at present for identifying prokaryotes but a similar approach could be used in the future once appropriate genes are found. Highly-trained taxonomists can
often identify whole specimen, but they cannot unambiguously identify fillets, processed product, or immature stages. Many
fish species are under threat due to extensive harvesting in fisheries and exploitation by aquarium trade. Because of these
pressures, conservation concerns and lists of threatened and endangered fish species have risen rapidly. There is also growing
evidence of consumer fraud as low-value species are substituted for more valuable species. As an example, 77% of red snappers sold in the United States are actually a mix of different species that includes some not-so-appreciated and rare reef fish.
How can DNA barcoding assist fisheries sustainability and increase consumer confidence? The first steps are to gather a comprehensive barcodes for fish species. The Canadian Barcode of Life Network represents the first national network dedicated
to large-scale DNA barcoding. DNA barcodes will be gathered for the 415 species of fishes from Canada’s Pacific waters and
538 fish species that occur in the Canadian Atlantic. Canada also sustains an active fishery in the Atlantic for 10 crustacean
species including lobsters, crabs and shrimps. Although based on a smaller number of species than fish, invertebrate fisheries
are important with lobster ($1 billion) and crab ($678 million) exceeding salmonid exports ($578 million). However, with overharvesting already seen in snow crab and northern shrimp, the industry is being encouraged to utilize new species. A recent
document has identified 26 crustacean species of potential commercial interest in Atlantic Canada. These include species such
as the jonah crab, rock crab, deep-sea red crab, toad crab, northern stone crab and porcupine crab. Since these crabs are likely
to increase in commercial importance, it is important to learn more about their biology. A COI-5’ identification system will enable
the identification of juvenile stages of these various species, aiding predictions of commercial stock size and production from
larval abundances. Barcodes will be obtained for these species as well as the 90 species of shrimp and 100 species of crabs
from Pacific Canada. This talk aims to introduce barcoding concepts and potential applications in fisheries technology.
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
107
New concepts to minimize seafood associated risks
Listeria monocytogenes inhibition by bio-film produced
from chitosan and divergicin M35
Benabbou R.1*, Zihler A.2, Desbiens M.3, Subirade M.1, Fliss I.1
1. Centre STELA, Institut des nutraceutiques et des aliments fonctionnels, Université Laval, Québec (Qc), Canada G1K 7P4
2. Institute of Food Science and Nutrition, Laboratory of Food Biotechnology, Schmelzbergstrasse 7 ETH Zentrum LFV C CH-8092 Zürich, Switzerland
3. Centre technologique des produits aquatiques, Ministère de l’Agriculture des Pêcheries et de l’Alimentation, Gaspé (Qc), Canada G4X 2V6
T
he ability of Listeria monocytogenes to grow at refrigerated temperature and in the presence of a relatively high salt concentration, make it difficult to control this pathogen in food particularly in ready-to-eat seafoods. The application of antilisterial
agent such as bacteriocin can control the growth of L. monocytogenes in food. However one of the practical problems associated with the use of bacteriocins is the stability of the bacteriocins within the food matrix. An alternative approach which could
be used to control this pathogen in food is to employ films containing the antimicrobial agents to control diffusion, improve the
stability of bacteriocin and prolong inhibition of L. monocytogenes growth. The objectives of this study were to determine the
antilisterial activity of chitosans of different molecular weights (MW) and degree of deacetylation (DDA) and to evaluate of the
sensitivity of L. monocytogenes to combinations of chitosan and divergicin M35. The development of an active bio-film made
from chitosan and divergicin M35 and evaluation of its antilisterial activity were also initiated. The antimicrobial activity of chitosan was monitored by the agar diffusion method, critical microdilution method and by determining the viable count of L. monocytogenes. Three preparations of chitosan with MW of 2, 20 and 100 kDa and DDA of 87.4% were chosen for their highest
antilisterial activity. The minimum inhibitory concentrations (MICs) of chitosans and divergicin M35 against L. monocytogenes
LSD 535 were 2.5, 2.5, 0.625 and 0.25 mg/ml, respectively. The combination of chitosan, whatever its molecular weight, and
divergicin M35 appeared to have an additive effect against L. monocytogenes as determined by fractional inhibitory concentration measurement. The developed bio-film with chitosan 100 kDa and divergicin M35 proved to be active at controlling the
growth of divergicin M35-resistant L. monocytogenes LSD 535 strain. In conclusion, results obtained in this study would be
helpful in the application of active bio-films of chitosan and divergicin M35 to inhibit L. monocytogenes in seafoods.
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Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
New concepts to minimize seafood associated risks
A novel procedure for the identification of Anisakis
simplex in seafood products by real time PCR
López I., Pardo M. A.*
Food Research Division AZTI Instituto Tecnológico Pesquero y Alimentario, Txatxarramendi ugartea z/g, E-48395 Sukarrieta Bizkaia
Introduction
Anisakis simplex is a parasite of marine mammals; the life cycle of the parasite can include one or more intermediary hosts,
their final hosts being marine mammals or large fish, in which the larvae develop until the adult stage is reached. When humans
eat the infected fish, raw or inadequately cooked, the nematode may enter the tissue of the gastrointestinal tract and then it
can cause different problems associated with gastric and abdominal infections and allergic reactions in previously sensitized
individuals.
The aim of this study was to develop a sensitive methodology to detect and quantify the presence of A. simplex (and indirectly
his allergens) in seafood products. For this purpose we used the Real Time PCR technology with a fluorogenic probes based
on TaqManTM chemistry (Applied Biosystems).
Methodology
Reference samples of 25 different fish species and 30 different commercial seafood products were purchased at local markets.
A. simplex individuals were obtained from guts of infected hakes. All samples were well characterised using taxonomic keys
or by PCR-Sequencing.
The mixture was homogenized in a Kinematica Polytron PT 10/35, and the DNA was extracted by using an alkaline lysis protocol and the Wizard-DNA Clean-Up Extraction Kit (Promega, Madison USA).
Real Time PCR reactions were run on the ABI PrismTM 7000 Sequence Detection System (Applied Biosystems). The primers
and the specific fluorogenic probe were designed using the Primer ExpressTM v2.0 software (Applied Biosystems).
A homogeneous group of seafood products were artificially contaminated with one A. simplex and subsequently analysed by
the Real Time PCR method with the aim of estimate the smallest number of replicates required to obtain feasible results. Data
were analysed using Statgraphics Plus 2.1 (STSC Inc., Rockville, MD) for one-way ANOVA. Least squares difference was used
for comparison of mean values among treatments, and to identify significant differences (P < 0.05) among treatment.
Results and Discussion
The Real Time PCR system was set up after estimation of optimal probe and primer concentration. A successful evaluation of
the cross-reactivity with 25 fish species was carried out to determine the specificity of the system. On the other hand, in order
to evaluate the linearity and sensitiveness of this system, a calibration curve was obtained using A. simplex DNA as template.
A detection limit of 0.1 pg of DNA was obtained with an efficiency of 99%.
After the analysis of a homogeneous group of eight seafood products artificially contaminated with A. simplex, the analysis of
variance indicates that we should take three replicates to obtain a trustworthy result of 99.9%.
As a result, we can conclude that this innovative method to detect the presence of Anisakis simplex in seafood products is
sensitive, robust and feasible.
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
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New concepts to minimize seafood associated risks
Modeling and predicting the growth boundary
of Listeria monocytogenes in lightly preserved seafood
Mejlholm O.*, Dalgaard P.
Danish Institute for Fisheries Research, Dept. of Seafood Research DTU, Building 221, Kgs. Lyngby, Denmark DK-2800
Objective
To develop a mathematical model that can predict the growth boundary of Listeria monocytogenes in lightly preserved seafood
as a function of product characteristics and storage conditions.
Methodology
The antimicrobial effect of diacetate and lactate against L. monocytogenes was evaluated in 12 challenge tests with vacuumand modified atmosphere packed (MAP) cold-smoked salmon and cold-smoked Greenland halibut at 8 °C. Products were inoculated with a mixture of L. monocytogenes isolates (100 CFU • g-1) and microbiological analyses were carried out with regular
intervals to determine changes in concentrations of L. monocytogenes. Product characteristics (pH, NaCl, organic acids and
smoke components) and storage conditions (temperature and atmosphere) of the different products were determined by additional analyses. In order to develop a growth boundary model for L. monocytogenes an existing model including the effect of
temperature, NaCl/water activity (aw), pH, lactate, nitrite and smoke components (phenol) was expanded with terms modelling
the effect of diacetate and CO2 as well as a term taking into account the inhibitory effect of interaction between all parameters.
This model was calibrated and validated on independent growth data obtained for L. monocytogenes in challenge tests using
lightly preserved seafood with well characterized product characteristics and storage conditions (n = 60). Finally, the developed
model was used to predict growth/no-growth of L. monocytogenes in lightly preserved seafood.
Results/conclusion
Treatment of MAP cold-smoked salmon with 0.15% (w/w) diacetate prevented growth of L. monocytogenes for more than
40 days at 8 °C whereas addition of 0.15% (w/w) diacetate only reduced its growth rate in MAP cold-smoked Greenland halibut. This difference between the two products was explained by a higher content of naturally occurring lactate in cold-smoked
salmon (0.80-1.0% w/w) as compared to 0.10-0.15% (w/w) in cold-smoked Greenland halibut. In fact, addition of 0.15% (w/w)
diacetate and 0.75% (w/w) lactate to MAP cold-smoked Greenland halibut prevented growth of L. monocytogenes for more
than 45 days at 8 °C. The applied concentrations of diacetate and lactate had no adverse effects on the sensory characteristics
of the studied products. The developed growth boundary model including the effect of diacetate, lactate, CO2, smoke components, nitrite, pH, NaCl/aw, temperature and interactions between all these parameters accurately predicted growth/no-growth
in 68 of 71 examined experiments from the present study (n = 24) as well as literature data (n = 47). Growth was predicted
for three batches of naturally contaminated cold-smoked salmon where no growth was actually observed indicating that the
model is slightly fail-safe. The developed growth boundary model facilitates identification of product characteristics and storage
conditions that prevent growth of L. monocytogenes in lightly preserved seafood and can be used as a means of securing safe
products in accordance with the new EU-regulation (EC 2073/2005) on ready-to-eat foods.
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Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
New concepts to minimize seafood associated risks
Evaluation of psychrotrophic lactic acid bacteria as
protective cultures for the biopreservation of seafood products
Matamoros, S.1,2*, Pilet M.-F.2, Prévost H.2, Leroi F.1
1. Laboratoire de Sciences et Techniques alimentaires marines, IFREMER, rue de l’Ile d’Yeu, BP 21105 44311, Nantes Cedex 3, France
2. Laboratoire de Microbiologie alimentaire et industrielle, ENITIAA, rue de la Géraudière, BP 82225 44322, Nantes Cedex 3, France
B
iopreservation is gaining attention among scientists and industrials as a natural way of increasing shelf-life of seafood
products and controlling their safety and quality. In a previous study, 52 lactic acid bacteria (LAB) strains were isolated
from seafood products and their inhibiting capacities were analysed in Petri dishes against 14 target strains belonging to the
spoilage or pathogenic flora of seafood products. Seven groups were determined, and one isolate was chosen in each group
for further investigation. These isolates were identified using phenotypical methods (lactic acid configuration, gas production,
API 50 CH fermentation profiles) and molecular methods (PCR amplification of the 16S-23S rRNA intergenic spacer region,
16S rRNA gene sequencing). Among the seven isolates investigated, three were identified as Leuconostoc inhae, two as Lactococcus piscium, one as Lactobacillus fuchuensis and one as Carnobacterium alterfunditum. In order to determine the inhibiting
activity of these strains, supernatant of stationary phase culture was tested on sensitive strains successively after heating,
adjustement at pH 6.5, catalase (for hydrogen peroxide activity) and proteinase K (for bacteriocin activity) treatment. For six out
of the seven strains investigated, the supernatant had no inhibiting capacities suggesting that the inhibition is dependant on the
presence of the bacterial cells. One of the supernatant tested showed a bacteriocin-like activity against Lactobacillus farciminis
EU2204 and Listeria monocytogenes EU2260.
Biopreservative abilities of the seven strains were then investigated on seafood products. The objectives were to check that
these strains had no spoiling activities, and to determine if they could increase the sensory characteristics and shelf life of the
product. Cooked shrimps were inoculated by the protective strains (around 105 CFU/g), vacuum packed and stored at chilled
temperature (8°C). Sensory analysis with a panel of seven trained judges and microbial counts were performed after one and
four weeks of storage and compared to a non-inoculated control. Microbial analysis showed that the inoculated LAB strains
grew from 105 - 106 UFC/g to 108 - 109 CFU/g in one week, and reached a level of 109 CFU/g after four weeks in all inoculated
products. Statistical treatment of the sensory analysis results showed that two strains improved greatly the sensorial quality of
the product : more than 80% of the judges considered these two samples as non-spoiled after four weeks of storage, whereas
the control sample was considered as spoiled. One of the strains reduced the sensorial quality of the shrimps, and the four remaining strains had a slight improving effect after four weeks of storage. However, no correlation could be established between
sensorial preservation and microbial population of Enterobacteriaceae or total flora. Following these promising results other
test using the protective strains on different seafood products will be realised.
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
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October 29th - November 1st 2006, Québec City, Québec, Canada
111
New concepts to minimize seafood associated risks
Comparison of the quality of fish fillets prepared onboard with and
without high pressure treatment at both 50 and 100MPa prior to freezing
Cadun A.1*, Schrubring R.2, Cakli S.1
1. Ege University, Faculty of Fisheries Department of Fishery and Fish Processing Technology, 35100 Bornova Izmir, Turkey
2. Bundesforschungsanstalt für Ernährung und Lebensmittel Forschungsbereich Fischqualität, Palmaille 9, 22767, Hamburg, Deutschland
Introduction
There was a patent of United States belonging to Unilever about the same subject. With this respect, treatment of very fresh
fish fillet by high pressure in the range of 0.1, 50, 100 MPa was applied prior to freezing to see if any differences occur. Apart
from the objective of the patent, influence of different ice storage periods prior to pressure treatment was determined. Also, red
fish and horse mackerel were used together with gadoid species used for the patent.
Methodology
Haddock, saithe, blue whiting, horse mackerel, red fish were caught by the fishery research vessel ‘Walther Herwig III’ in summer 2004. Samples were divided into groups. Pre rigor samples were shortly after being caught, they were gibed for bleeding,
washed, filleted, skinned in pre rigor condition and vacuum packed and sealed in PE bags and stored in a refrigerator at 3-5 ºC
until pressure treatment, fillets were subjected to high pressure treatments at 0.1, 50, 100 MPa for 20 min, repacked under
vacuum, frozen at -30 ºC and stored at -24 ºC until investigation. Post rigor samples were shortly after being caught they were
gibed for bleeding, washed, stored in ice for 24, 48 or 96 h, filleted, skinned, iced for a short period of time and vacuum packed
and sealed in PE bags and stored in a refrigerator at 3-5 ºC until pressure treatment, fillets were subjected to high pressure
treatments at 0.1, 50, 100 MPa for 20 min, repacked under vacuum, frozen at -30 ºC and stored at -24 ºC until investigation.
Analysis
Crude fat, crude protein, moisture, ash were determined as proximate composition, pH value were determined as physicochemical analysis, colour measurements were performed on fillets and homogenate prepared from fillets using a spectro pen, cook
loss of whole fillets and parts of fillets were determined, expressible moisture was determined using a modification of the filter
paper press method, texture measurement was performed as instrumental texture profile analysis using a SMS Texture analyser TA.XT 2/25 according to Schubring (2001). The texture parameters hardness, chewiness, resilience and cohesiveness,
springiness, adhesiveness, elasticity were estimated by double compression of the sample. Protein denaturation of different
fish species was determined using a SETARAM Micro DSC III. Water and salt soluble proteins were determined as protein
solubility. DMA- N, TMA-N, and TMAON were determined by gas chromatography as chemical analysis. Triangle test was used
for sensory evaluation.
Results
The trends were not consistent in DSC, protein solubility, sensory, colour, pH value, cook loss, texture, expressible moisture
and chemical analysis when comparing the pressure treatments and different ice storage periods.
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Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
New concepts to minimize seafood associated risks
Identification and characterization of bacterial isolates
capable of degrading paralytic shellfish toxins
Donovan C.1*, Gill T.1, Allen D.2, Garduno R.2, Ku J.1, Quilliam M.3
1. Department of Process Engineering and Applied Science, Dalhousie University, Halifax (NS) Canada B3J 2X4
2. Deparment of Microbiology and Immunology, Dalhousie University, Halifax (NS) Canada B3H 1X5
3. Institute for Marine Biosciences, NRC, Halifax (NS) Canada B3H 3Z1
P
aralytic shellfish toxins (PST), the causative agents of paralytic shellfish poisoning (PSP), are potent neurotoxins produced
by several strains of marine dinoflagellates and some bacteria. Implicated in serious toxin outbreaks globally, these toxins
primarily accumulate in filter feeding bivalves and are passed through the food chain to other marine creatures and humans.
Previous studies have shown that some bacteria are capable of transforming PST. The current study involves 57 bacterial
strains isolated from blue mussels (Mytilus edulis) in the summer of 2003. Out of the 57 isolates, 19 were found to degrade
PSTs in an algal extract when incubated with mussel extract and marine broth. Toxin degradation did not occur in the presence
of mussel extract and marine broth alone. Preliminary identification of the isolates by 16S rDNA sequencing suggests they are
closely related to the genera Pseudomonas and Pseudoalteromonas. The results of this study could have a significant impact
on both economical and public heath aspects of the aquaculture industry and for the first time point toward a practical means
of in vivo toxin elimination.
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
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October 29th - November 1st 2006, Québec City, Québec, Canada
113
New concepts to minimize seafood associated risks
The Chill-on integrated project
Bogason S.* and the project team 24 partners (WEFTA)
Title of project: « Developing and integrating novel technologies to improve safety, transparency - test case fish and poultry »
T
he CHILL-ON project is a European Community, funded Integrated Project that started on 1 July 2006. Its total budget is
15 million Euros and the grant funding is 9.8 million Euros. The project has 24 partners and will be running for four years,
until July 2010. The main focus of the project work will be directed to the fish supply chains, and will research and develop new
approaches and concepts to improve the quality, safety, visibility and traceability of the chilled/frozen food supply chain. The
outputs of this project will be integrated into a holistic approach to deliver an integrated solution, to significantly enhance the
state of the art of the entire food supply chain from - « fork to farm ». The project should result in a novel concept for tracking
and tracing - « TRACECHILL » to include input from novel biosensors for low temperature micro organisms, novel chilling and
packaging technologies and smart labelling.
To achieve the objectives of the CHILL ON project, four major objectives have been defined:
Objective 1 - Risk Assessment of the chilled/frozen food supply chain by development and procurement to identify and quantify
principle important issues:
•
A Quantitative Microbiological Risk assessment of the entire chilled/frozen supply chain to enable the identification of the most critical
points along the supply chain.
•
A combined QMRA- HACCP tool, that can be implemented into the Decision Support System (DSS) to achieve real time inputs for the
risk assessment.
•
Risk assessment of packaging design under transport and storage.
•
Supply Chain Assessment (Technical, Economic, Regulatory, Technology Preferences).
Objectives 2 - Research, develop and validate cost-effective bio sensing technologies for the qualitative and quantitative detection of low temperature micro-organisms:
•
Quantitative Polymerase Chain Reaction-QPCR for the real-time detection of low temperature microorganisms.
•
Immunoassay microarray for low temperature microorganisms detection.
•
Quantitative microarray DNA-DNA hybridization for low temperature microorganisms detection.
•
Enrichment of bacteria and molecular markers by ligand grafting.
Objectives 3 - Research, develop, validate and scale-up cost-effective low temperature transport and storage supporting technologies to extend produce shelf life
•
Research, development and optimization of the «bubble slurry ice» technology based on the patented Wiped surface Crystalliser
System.
•
Develop specific protocols for fish chilling techniques at different stages in the chilling chain from catch to consumer.
•
Optimization of the whole chain for lowering and maintaining low temperature with regard to maximizing quality and safety of the
products and minimizing costs and energy uses.
Objective 4 - Research, develop of Information and Communication Technologies (ICT) to improve traceability, supply chain
management and quality management.
114
•
Research and develop novel smart labels: Time Temperature Indicators (TTI), Radio Frequency Identification (RFID) and the eCHILLON smart label (coupled TTI and RF technology).
•
Novel Mobile management Unit (MMU) for the transport phase.
•
New developed e-SCM (electronic Supply Chain Management) based on Internet, GPS (Global Positioning System) and GIS (Geographic Information System).
•
Decision Support System (DSS).
•
Biosensors inputs – to monitor the quality and safety in real-time.
•
Dynamic risks evaluation by combining the QMRA- HACCP tool into the DSS.
•
Provide real time information to the users.
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
New concepts to minimize seafood associated risks
Antibacterial properties of garlic oil, oregano oil and chitosans
to Salmonella enteritidis cultured at different temperatures
Marques A.*, Encarnação S., Pedro S., Nunes M. L.
Department of Technological Innovation and Valorisation of Fishery Products (DITVPP), Portuguese Institute of Sea and Fishery Research
(IPIMAR) Portuguese National Institute of Agrarian and Fishery Research (INIAP), Avenida de Brasília 1449-006 Lisbon, Portugal
A
lthough seafood is very important for human nutrition and health, it is also very perishable mainly due to its intrinsic characteristics and biological composition. Seafood producers and processors are actively in quest of alternative preservation
methods to respond to consumers’ demand, assuring microbiology safety and keeping the nutritional quality at a high level.
Within the processing technologies, the use of natural antimicrobial substances combined with edible coatings, have potential
application to seafood and minimal risks to consumers. Edible coatings consist of thin layers of films creating a physical barrier
between the food and its environment. The purpose of the present study is the evaluation of the antibacterial ability of three
natural antimicrobial substances (garlic oil, oregano oil and chitosans) against the human pathogen Salmonella enteritidis
cultured at different temperatures (10 ºC and 20 ºC).
The experiments were carried out with the bacterial strain Salmonella enteritidis (ATCC 13076) cultured in brain heart infusion
broth (BHI). Different concentrations of garlic oil (0-5%), oregano oil (0-2%) and chitosans (0-10%) were tested. Initially, garlic
oil was diluted with ethanol (10-50% v/v), oregano oil was diluted in BHI (10% v/v), and chitosans (1- 2%v/v) were diluted in an
acetic acid solution (1% v/v). Nine replicate flasks were prepared for each treatment. In each flask, 50 µL of dilute antimicrobial
substance was supplemented to 4.95 ml of BHI inoculated with a 24h grown S. enteritidis culture (103-104 CFU/ml). As control
treatments, bacteria were cultured with ethanol, acetic acid or BHI, instead of using respectively garlic oil, chitosans and oregano oil. Each treatment was incubated in anorbital shaker at 125rpm, 10 ºC (during 144h) or 20 ºC (during 48 h). One replicate
of each treatment was periodically removed and sampled (each 24h -10 ºC; 6h - 20 ºC). The samples were serially diluted in
sterile BHI and 0.1 ml of each dilution was spread onto tryptic soy agar (TSA) plates (n=2). The plates were then incubated at
37 ºC for 24 h and viable bacteria were counted.
Preliminary results indicate that the three antimicrobial substances were able to completely eliminate the growth of S. enteritidis, independently of the temperature used. Oregano oil always presented the strongest antibacterial properties (minimum bactericidal concentration - MBC of 0.05% at 10 ºC), followed by garlic oil (MBC of 1% at 10 ºC) and by chitosans (MBC of 3% at
10 ºC). At higher temperatures (20 ºC) the antimicrobial substances were not so effective than at lower temperatures regarding
their growth, as higher concentrations were required to avoid bacterial growth. Although the strongest antibacterial properties
were presented by oregano oil the three natural antimicrobial substances are promising tools that can be used to minimize the
bacterial contamination during seafood processing (thus increasing the microbiological safety of these products), to extend its
shelf-life, to keep its biochemical and sensory quality during preservation, and to reduce seafood waste.
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
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New concepts to minimize seafood associated risks
Enteric viruses in bivalve molluscs from
Portuguese production areas
Silva H.S.*, Palma M.
INIAP/IPIMAR, Departamento de Inovação Tecnológica dos Produtos da Pesca
B
ivalve molluscs are capable of filtering large volumes of water, to obtain the nutrients and oxygen they need, and simultaneously ingesting bacteria and virus which they concentrate in their body. Some of these microorganisms are pathogens
like Escherichia coli (E. coli), Vibrio, Norovirus, hepatitis A virus and enterovirus from faecal contaminated no-treated urban
residual waters, aquaculture and agriculture residues, boat discharges and others.
The Regulation n. 854/2004 issued by the European Parliament establishes for live bivalve molluscs from classified production areas, health standards based on faecal contamination indicators like E. coli, which generally are not correlated with the
presence of virus. Nevertheless, bivalve molluscs are often consumed raw or hardly cooked as the traditional way of cooking
does not assure the harmlessness of these foods. So, bivalve consumption configures an increased public health risk and often
contributes for foodborne viral gastroenteritis and hepatitis A infection disease. Virus are rather resistant to chlorine and other
treatments which are applied to residual and waste waters and can survive to adverse environment conditions for years. Present depuration techniques effectively eliminate bacteria agents but not the viruses. Thus, several studies throughout Europe
have been made the past years to establish detection methodologies for Hepatitis A (HAV) virus in bivalve molluscs and to
evaluate the degree of contamination in production areas. Within the present work, HAV was detected by RT-PCR and nestedPCR against known controls. Several sets of primers as well as different amplification conditions were tested. The distribution
of virus around Portuguese shellfish production areas and within different species is presented. Results seem to indicate 16%
of positive samples and a major incidence of the virus in mussels and carpetshell. A correlation between environmental conditions with virus incidence along the year is also proposed.
This work was financed by QCA III-22-05-01-FDR - 00032 «Aplicação de novas metodologias analíticas à qualidade dos recursos» and QCA III - 22-05-01-FDR-00023 «Reforço da capacidade laboratorial do IPIMAR» .
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Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
New concepts to minimize seafood associated risks
Quantification of Total Viable Bacteria on Fish Fillets
by using the Polymerase Chain-Reaction
Lee J.-L., Levin R.E.*
Department of Food Science, University of Massachusetts Amherst
R
eal time PCR based on universal primers for amplification of a highly conserved bacterial 16S rDNA sequence was utilized
in conjunction with the treatment of extracted bacterial cells with ethidium bromide monoazide for the differential enumeration of viable and dead cells on cod fillets. Amplification of DNA from dead bacterial cells was successfully inhibited by EMA,
whereas the DNA from viable cells was readily amplified. The detection range of the EMA real-time PCR assay was linear from
1 to 100,000 mixed bacterial genomic targets per PCR derived from broth cultures of fish tissue. The minimum detection limit
of bacteria was found to be 10 genomic units/real-time PCR, equivalent to 100,000 CFU per gram of tissue. The EMA real-time
PCR allowed construction of a standard curve obtained by plotting the log of genomic targets from strictly viable cells against
resulting Ct values that facilitated quantification of total viable bacteria from fish fillets. The log of the total number of genomic
DNA targets from EMA treated cells and plate counts from six randomly procured cod fillets were found not to be statistically
different with the exception of one fillet.
The process of freezing and thawing fillet tissue resulted in a drop in mean CFU detected by plate counts from log 8.5 + 0.2 to
log 8.1 + 0.1. A similar reduction in genomic targets from 8.5 + 0.1 to 8.0 + 0.16 was detected by EMA real- time PCR.
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
117
New concepts to minimize seafood associated risks
Seafood-processing: a key strategy to reduce
cadmium and arsenic related health risks in sea scallop
(Placopecten magellanicus) consumption
Tita G.*, Saint-Louis R., Pelletier É.
Institut des sciences de la mer, Université du Québec à Rimouski, 310, allée des Ursulines, Rimouski (Qc) Canada G5L 3A1
S
everal commonly consumed bivalve species are known to bioaccumulate cadmium (Cd) at levels above those observed
in most other bivalves, although background concentrations may be low. This generates some health and economical
concerns when bioaccumulated levels are above the authorized limits established by governmental or non- governmental
agencies. Wild and farmed sea scallop (Placopecten magellanicus) populations in the St. Lawrence gulf have a high Cd profile, while representing an important resource for the regional fisheries and aquaculture industry. The present study consisted
in investigating the cadmium distribution among four anatomical components, i.e. muscle, digestive gland, gonad and «rest».
Samples of wild and farmed sea scallops were collected from May through September 2004. Chemical analyses also included arsenic (As) in order to assess As absorption through scallop consumption. Analyses focused on As speciation in order
to specifically quantify its inorganic fraction, which is its toxic component and the mostly used in health risks assessments.
This investigation showed that approximately 95% of Cd and 40% of total As are concentrated in the digestive gland., while
significantly smaller fractions were found in the muscle (Cd: 0,7% As: 17%) and the gonad (Cd: 0,4% et As: 16%). Inorganic
As varied between 7 and 80% of total As, according to the sampling period and the anatomical components (muscle <15%;
digestive gland > 30%). If sea scallop soft tissues are analyzed as a whole, cadmium concentrations vary between 1-3 µg•g-1
(wet weight), which is above the limit of 1 µg•g-1 established by the European Union, as well as above the current deliberation by the CODEX Alimentarius Commission who decided to adopt the same standard as the EU. However, as Cd is mainly
concentrated in the digestive gland, the concentrations found in the muscle (<0.3 µg•g-1) and the gonad (<0.5 µg•g-1) meet
the above-mentioned limits. Total arsenic levels (whole animal: 2-8 µg•g-1; muscle <3 µg•g-1; gonad <6 µg•g-1; digestive gland
10-40 µg•g-1) were never found to be above the limits established by any country, implying that its inorganic fraction was well
below health or normative limits. Our study shows that, if on one hand arsenic is not a problematic issue, on the other hand
cadmium raises some concerns. However, the latter may be overcome by processing scallops and by commercializing and
consuming only selected anatomical components of their soft tissues, i.e. muscles and gonads.
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Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
New concepts to minimize seafood associated risks
Enumeration of Staphylococcus spp. and S. aureus
in salted seafood by using a direct viable count
fluorescent in situ hybridisation protocol
Pedro, S.1*, Oliveira, M.2, Nunes, M.L.1, Bernardo, F.2
1. DITVPP-INIAP/IPIMAR, Av. Brasília 1449-006 Lisboa, Portugal
2. CIISA/Laboratório de Inspecção Sanitária Polo Universitário da Ajuda, 1300-477 Lisboa, Portugal
F
ood-borne diseases are of major concern worldwide, being Staphylococcus aureus a leading cause of gastroenteritis. This
food poisoning is due to the absorption of staphylococcal enterotoxins preformed in the food. Although cooking destroys
the bacteria, the toxin produced is heat stable being not destroyed by this treatment. Staphylococcal food poisoning occurs
most often in foods that require hand preparation and are exposed to temperature abuse, including fisheries products such as,
breaded seafood, rehydrated dried and/or salted fish and seafood salads.
The conventional methods for enumeration take about 2-4 days and depend on demonstration of diagnostic characteristics
and recovery of damaged cells. An improved protocol, involving an incubation step of the sample with ciprofloxacin and including six steps (fixation with paraformaldehyde, permeabilisation with lysostaphin and ethanol, hybridisation with two 16S rRNA
oligonucleotide probes, stringency washes and observation by fluorescence microscopy) was applied to salted cod samples
in order to enumerate the targeted bacteria. Results show that this protocol can be successfully applied to direct analysis of
salted seafood samples, distinguish between live and dead bacteria, being rapid, easy to perform, sensible, reproducible and
not expensive
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
119
New concepts to minimize seafood associated risks
Arsenic speciation in seafood: algae, sea urchin and molluscs
Saint-Louis R.*, Tita G., Pelletier É.
Institut des sciences de la mer, Université du Québec à Rimouski, 310, allée des Ursulines, Rimouski (Qc) Canada G5L 3A1
H
igh concentrations of heavy metals such as lead and cadmium in seafood is usually associated with marine pollution, but
the picture is quite different with arsenic because it naturally occurs at high levels in marine plants and animals. From a
human health point of view it is important to develop tools to evaluate risks related to arsenic in seafood. Among these tools the
chemical analytical procedures as well as the knowledge of arsenic fate in species with commercial value are of fundamental
importance. The arsenic concentration varies among species; in algae harvested along the St. Laurent Estuary shores arsenic
was quantified (dry weight) at a level of 40 µg•g-1 in Laminaria spp., 16 µg•g-1 in Porphyra spp. and 9 µg•g-1 in Ulva spp. The
concentration varies also within an animal, between tissues. For instance, in the sea scallop Placopecten magellanicus living
in the marine waters of the St. Laurent estuary and gulf, arsenic concentrations range between 210 µg•g-1 in the digestive
system and 6 µg•g-1 in the muscle. In the green sea urchin Strongylocentrotus droebachiensis gonads contain arsenic at about
12 µg•g-1, which is half the concentration found in its digestive system. But not all the arsenic is in a toxic form. Most of the
arsenic exists in seafood as organic compounds with low toxicity, readily excreted by consumers. Thus the associated risk to
arsenic is related to the proportion of its toxic inorganic forms within the edible parts of the products. In most algae species,
over 95% of arsenic is present as no-toxic and this figure has been applied to many seafood products. However, this does not
apply to all products on the market and speciation of arsenic is essential.
We present our strategy to analyse arsenic and its specific compounds in seafood. Automated extraction of samples with
a ASE200 Dionex system has been optimized and analytical techniques based on liquid chromatography coupled to mass
spectrometry with ionisation via plasma (LC-ICP-MS) or electrospray (LC-ESI-MS) are used to discriminate between arsenic
chemical species. The study also shows that chemical arsenic assessments should be tissue-based when analyzing animals.
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Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
New concepts to minimize seafood associated risks
Quality of life - integrated benefit and risk analysis.
Web-based tool for assessing food safety and health benefits
Bogason S.*, Yngvadóttir E.
Icelandic Fisheries Laboratories, Skulagata 4 101, Reykjavik, Iceland
Q
ALIBRA - Quality of life - integrated benefit and risk analysis. Web-based tool for assessing food safety and health benefits
is the name of a project funded by the European Community’s Sixth Framework Programme, Priority 5, Food Quality &
Safety. It began in April 2006 and will end in 2009.
To assess the balance between the risks and benefits associated with a particular food, they must be converted into a common
measure of net health impact. Uncertainties affecting the risks and benefits cause uncertainty about the magnitude and even
the direction of the net health impact. QALIBRA will develop methods that can take account of multiple risks, benefits and
uncertainties and implement them in web-based software for assessing and communicating net health impacts.
The overall objectives of QALIBRA are to develop a suite of quantitative methods for assessing and integrating beneficial and
adverse effects of foods, and make them available to all stakeholders as web-based software for assessing and communicating
net health impacts.
To achieve these objectives QALIBRA will:
- Develop a generalised modular approach to risk-benefit analysis using menus of dose-response and valuation
functions.
- Implement the risk-benefit analysis methods developed in QALIBRA in web-enabled software that is available for use
by all stakeholders via an integrated website.
- Develop targeted risk communication strategies for integrated risk-benefit analysis, adapted to the needs of different
stakeholders.
- Use the methods and software developed by QALIBRA to carry out comprehensive risk-benefit analyses for selected
food groups including oily fish and functional foods, for selected EU populations.
The participants in the project are: Icelandic Fisheries Laboratories, Iceland, coordinator, Central Science Laboratory, United
Kingdom, National Institute of Public Health and The Environment, The Netherlands, Wageningen University, The Netherlands,
University of Patras, Greece, Altagra Business Service, Hungary, National Institute for Agriculture and Fisheries Research,
Portugal.
For more information contact Eva Yngvadóttir (IFL), coordinator, [email protected]
The QALIBRA project has established a collaborative effort through clustering with another EU project called BENERIS (contract
N°022936).
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
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October 29th - November 1st 2006, Québec City, Québec, Canada
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Advances in Processes and
Added Value of Products
Poster session
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
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October 29th - November 1st 2006, Québec City, Québec, Canada
123
Advances in processes and added value of products
P-11
A new model of twin-screw extrusion process
and application to marine bio-resources
Vauchel P.1,2, Baron R.1, Kaas R.1, Bergé J.P.1*, Arhaliass A.2, Legrand J.2
1. IFREMER, Departement Sciences et Techniques Alimentaires Marines
2. UMR CNRS 6144, Génie des Procédés - Environnement et Alimentaire
E
xtrusion process use has developed during the last decades, and is nowadays largely exploited in the food and polymer
industries. It is still very promising since its flexibility allows to work on a large variety of raw materials, and to get products
with a wide range of properties. Few applications have already been developed on seafood products, notably on fish flesh or
fish by-products (Baron, 1995 or Baron et al., 1996) or on algae (Doi et al., United States Patent n°3, 901,873), and should find
other developments be that on seafood products or by-products. Extrusion process main advantages, in addition to being a
low water demand process, are compactness, modularity and continuity. Nevertheless, up to now, phenomena taking place in
the extruder, especially concerning flows and transformation of the material during the process, are not completely understood.
Extrusion is still considered as a process which is hard to modelize, simulate, design and control.
Several authors (Ainser, 1996, Puaux et al., 2000) have studied the residence time distribution in twin-screw extruders, by fitting experimental RTD curves with different flow models. Good correlations have been performed, especially with the backflow
cell model and the axial dispersion model. Nevertheless those models don’t directly take into account the geometrical parameters (screws profile and die design) and the control parameters (screw speed and feed rate). This point limited the prediction
value of this modelling approach.
In this study, a simple new model is proposed to predict the residence time distribution (RTD) in fully intermeshing co-rotating
twin-screw extruders. This model is based on an extension of an axial dispersion model, including control parameters (screw
speed and flow rate) and geometrical parameters, enabling to take into account the screw profile and the die design. A simplified solution of Navier-Stokes equations, describing velocity, flow, length of fully filled screw and pressure at steady state, has
been coupled to an axial dispersion model, describing the evolution in time and in space of the concentration of a tracer. We
have chosen to extend it to the case where the axial dispersion coefficient and the fluid velocity are piecewise constant along
the flow axis, depending on the fully filled length.
Simulations have been performed for a BC45 extruder to illustrate the large evolution of RTD in function of the control and
geometrical parameters. A comparison between simulation results and RTD experimental data (Puaux et al.) was performed.
A good correlation was obtained showing the predictive nature of the model.
The new model summarily presented here, doesn’t aim at improving experimental data fitting, but may be so far interesting in its
ability to predict the impact of geometrical parameters on the residence time distribution. It could provide a precious help whilst
designing installations of industrial size. Nevertheless, an important work remains to be done before intensive use, especially
extensions of the model to take into account viscosity evolutions in along the screws and chemical reactions, with a concentration which could be linked to the viscosity .
124
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
Advances in processes and added value of products
P-6
A restructured fish product similar to fillet
slices made with cold technology
Moreno H., Carballo J., Borderías A.J.*
Instituto del Frío (CSIC), Ciudad Universitaria, Madrid, Spain
A
mong the possibilities for restructuring fish muscle is the one based on cold gelification by adding certain ingredients with
which it is possible to obtain thermo-stable gels that can imitate high-added value products with raw fish appearance (raw
fish fillet analog, smoked fish slices, marinated fish fillets, etc.).
Using cold gelification, the aim of this work was to obtain a raw fish fillet analog from minced hake muscle (Merluccius capensis), restructuring it so that it acquired the appearance of fish fillet with its myotomes and myosepts.
To obtain the formula of the restructured product, which was going to be the base product to constitute the myotomes in the
form of 3-10 mm thick slices, the Response Surface Methodology (RSM) design was used, and the variables were concentrations of NaCl (0.0-3.0%), sodium alginate (0.05-0.5%) and different sources of calcium (chloride, lactate and calcium caseinate
between 0.1-1.0%). These compounds allow gelification at refrigeration temperatures (2-8 ºC) for 24 hours. The analyses done
to choose the most convenient formula were: mechanical analysis (texture profile analysis, puncture test) and water binding
capacity (cooking drip).
For the myosept imitation, a mixture of water with viscous appearance and a whitish colour containing transglutaminase in
1.5-6.0% proportions was prepared which was applied to the surface of the two slices of restructured fish. After the « sandwich »
of alternative layers imitating myoseptsand myotomes was cut transversely to look like fish muscle slices.
From the analysis of the statistical design used for the formulation of the « myotomes », the formula chosen consisted of
minced muscle with 1.5% NaCl, 0.3% sodium alginate and 0.5% CaCl2 added, due to the fact that the slice exhibits some
characteristics of hardness, cohesiveness and elasticity more similar to those of real fish muscle. For the viscous liquid formula
that was going to be the « myosepts », the one was chosen that had the greatest adhesion and best appearance, even after
cooking. The final result was a product similar to fish pieces or slices with the usual appearance of myotomes and myosepts,
and with a general texture similar to the real product.
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
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Advances in processes and added value of products
P-36
Alginate-whey protein granular microspheres
as oral delivery vehicles for bioactive compounds
Chen L.*, Subirade M.
Chaire de recherche du Canada sur les protéines, les bio-systèmes et les aliments fonctionnels, Institut de recherche sur les nutraceutiques
et les aliments fonctionnels (INAF/STELA), Faculté des sciences de l’agriculture et de l’alimentation, Université Laval, Pavillon Paul Comtois,
Québec (QC) Canada G1K 7P4
A
lginate (AL)-whey protein isolate (WPI) microspheres of varied WPI/AL ratio, particle diameter and concentration of polymer bead forming solution (CAL + WPI) were prepared in order to develop a biocompatible vehicle for oral administration of
bioactive compounds. Microscopy revealed a special matrix/granular structure for microspheres with a WPI/AL ratio of 8:2, 100
μm diameter and CAL + WPI of 5% (AL-WPI A2), featuring WPI granules 3-10 μm in diameter homogeneously distributed within
an AL spherical matrix. The compound release properties of these microspheres were investigated in simulated gastric and
intestinal fluids (SGF and SIF). They demonstrated the desirable property of retarding riboflavin release in SGF and underwent
alginate matrix erosion together with liberation of WPI granules in SIF, followed by complete release of the riboflavin. Riboflavin release in SGF and in SIF without pancreatin followed the Higuchi diffusion model while release in SIF in the presence of
pancreatin was attributed to WPI granule degradation.
This work was supported by the Fonds Québécois de la Recherche sur la Nature et les Technologies (Action Concertée
FQRNT-AEE-MAPAQ-MIC sur les nutraceutiques et les aliments fonctionnels).
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Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
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October 29th - November 1st 2006, Québec City, Québec, Canada
Advances in processes and added value of products
P-30
Assessing the effect of post-harvest processes on the quality
of live cultured mussels from Gaspé Peninsula, Québec, Canada
Coulombe F.*, Paradis J., Tremblay M., Samuel A., Coulombe N.
Centre technologique des produits aquatiques, MAPAQ, Gaspé (QC), Canada
F
rom May 2005 until July 2006, several post-harvest observations has been realized with farmed mussel from Gaspé peninsula. The goal was to assess handling practices from harvesting through to processing, to distribution and to retail outlets.
Continuous monitoring of mussel’s container temperature has been registered with mini-log recorders for exploring variations
in the cooling chain. The impact on the valve gaping, propensity to spawn, off-flavours and the incidence off broken shells has
been noted. All of these criteria being off crucial importance for buyers. So, critical points has been identify to provide useful
guidelines to each participant in the trade. The most significant observation is that the rate of gaping in the mussels of Gaspésie
was definitely higher in targeted markets than those ones from Prince-Edward-Island or Newfoundland. Our observations also
show that mussel gaping was rather weak at the processing plant in Rivière-au-Renard. In fact, it seems related to the fact that
handling of mussels before processing was quite different in Gaspésie compare to other growing areas in eastern Canada.
Thus, we conclude that it would be necessary to further standardize operations. Another option should be the inclusion of a
hydrocooling stage in the processing line. It should probably reduce gap opening to an acceptable level while being more easily
manageable.
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
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October 29th - November 1st 2006, Québec City, Québec, Canada
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Advances in processes and added value of products
P-8
Characterization of squid surimi
made by two different methods
Borderías A. J.*, Campo L., Fernández-Martín F.,
Pombo M.J., Sánchez-Alonso I., Solas M., Tovar C.
Instituto del Frío (CSIC) Madrid, Spain
Universidad Complutense, Madrid, Spain
Universidad de Vigo, Ourense, Spain
T
he objective of this work was to characterize surimi made from giant squid (Dosidicus gigas) by two methods. The first
consisted in initial dispersion of muscle in a neutral salt solution followed by refining and isoelectric precipitation (Lot A);
the second consisted in washing minced muscle with a buffer citrate-phosphate at pH 5 and refining (Lot B). In both cases a
decanter was used to collect the precipitate, and then 4% sorbitol, 4% sacarose and 0.5% sodium tripolyphosphate was incorporated. The pH of the surimis was about 5.
In both cases the microstructure of gels made from both surimis was very similar when 3% salt was added, and they presented a very compact network without the spongy appearance characteristic of thermally formed gels made from other kinds of
surimi.
Myofibrillar protein degradation was studied by electrophoresis. The myosin heavy chain (MHC) was depleted as compared to
whole squid muscle. The depletion of MHC coincided with intensification of the other HMM bands at 132 kDa .
In viscoelastic testing, the results of frequency and stress sweep tests of both surimis at 10 ºC showed that Lot A had higher
viscoelastic gel strength. Thermal sweep tests were conducted at 0.1 Hz and 1 ºC/min in neutralized samples with and without
addition of 3% of salt. There was gelification in all samples, but the phase angle was lower at the same temperature when 3%
of salt was added, which indicates that it is important to add 3% salt to achieve better gels.
Also, a punch test to breaking point was performed on thermally induced gels made from both surimi lots, yielding similar values
of work of penetration: Lot A= 419 gxcm and Lot B= 414 gxcm.
DSC (TA, Q-1000) traces were conducted on the two surimi types in both neutralized and no-neutralized conditions. Lot-A surimi showed a very smooth pattern with no distinction between proteins; maximum occurred at about 66 °C, and denaturation
enthalpy was low (4.6 J/g). The neutralized sample exhibited myosin and actin components differentiated by peaks at about
45 and 75 °C respectively, and a total denaturation enthalpy of 7.9 J/g, considerably greater than when it was not neutralized.
Lot B was more fully resolved and yielded greater denaturation enthalpies than Lot A. Non-neutralized Lot B presented a highly
pronounced actin region, as if it the actin content were higher and/or the destabilization effect of salt were less. Maximum effect
was registered at about 73 °C, close to the actin maximum; myosin was only visible as a small shoulder at about 50 °C, and
the denaturation enthalpy was 5.9 J/g. Neutralized Lot B surimi presented the typical trace of myofibrillar proteins with myosin
(maximum at 45.5 °C) and actin (maximum at 76.5 °C), quite differentiated and with a total denaturation enthalpy of 10.6 J/g,
which is still somewhat lower but much closer to typical figures of actomyosin systems from cold-water fish species.
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Advances in processes and added value of products
P-2
Concentration and deodorization of white fish
peptides using ultrafiltration and nanofiltration
Vandanjon L.1*, Chabeaud A.1,2, Guérard F.2, Jaouen P.3, Bourseau P.1
LETEE Université Bretagne Sud EA 3373 Lorient, France
ANTIOX Université Bretagne Occidentale Quimper, France
GEPEA UMR CNRS Université de Nantes 6144 Saint-Nazaire, France
T
his study was carried out within the framework of the European Program SEAFOODPlus1, having the aim of promoting the
consumption of seafood products in Europe. SEAFOODPlus, with its 80 partner establishments, has the aim of tackling the
following problems: health issues, traceability, microbiological quality and biotechnological treatment of fishery by-products.
This latter point consists in an enzymatic hydrolysis of proteinic substrates to produce biologically active molecules; our role is
to implement membrane processes to concentrate, to desalt and to fractionate the hydrolysates. The performances of different
ultrafiltration (UF) and nanofiltration (NF) membranes were estimated by measuring permeate fluxes and retention rates.
Ultrafiltration : two monotubular alumina membranes (cut-off : 1000 and 5000 Da) and one flat-plate polyethersulfone membrane (cut-off : 3000 Da). A higher flux was observed with the 5000 Da membrane than with the two others (120 L•h-1•m-2 at
4 bar and 20 °C for a solution at 6 g•L-1) but similar retention rates were noticed. However, this membrane did not perform efficiently when used for concentrating the hydrolysates and for deodorizing them by diafiltration. The peptide content increased
only by 25% when the solution was concentrated 3 times and diafiltered 1.5 times. Interestingly, this membrane proved to be
effective for the fractionation of a peptide mixture, given that its retention rate was not so high (approximatively 75% for the
initial solution).
Nanofiltration : spiral polyamide membrane (cut-off : 300 Da).
With a Volume Reduction Factor of 10, a Mass Concentration Factor of 6 and a satisfactory flux (17.5 L•h-1•m-2 at 12 bar at the
end of the concentration), the NF membrane is more useful for the concentration and the deodorization of the peptides. The
retention rate increased progressively to reach approximatively 95%, and showed to be independent of variations of pH and
salt concentration.
The concentrated solution was washed by diafiltration with elevated Number of Diavolumes (NDV = 12). The odour of fish
decreased quickly after the first two diavolumes, then less quickly thereafter. Therefore a partial deodorization at a low NDV is
feasible.
1. http://www.seafoodplus.org
This work was performed within the Integrated research Project SEAFOODPlus, Contract n° FOOD-CT-2004-506359. The
partial financing of this work by the European Union is gratefully acknowledged.
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Advances in processes and added value of products
P-57
Cost-effective methods for extracting
proteins from whitefish bones
Plante S.1,3*, Oliveira A.C.M.1, Sreenivasan A.1, Smiley S.1, Bechtel P.J.2
1. Fishery Industrial Technology Center, University of Alaska, Fairbanks School of Fisheries & Ocean Sciences Kodiak, Alaska USA
2. United States Department of Agriculture/Agricultural Research Service, Subarctic Agriculture Research Unit, University of Alaska, Fairbanks
School of Fisheries & Ocean Sciences Fairbanks, Alaska USA
3. Coastal Zones Research Institute, 232B rue de l’Église Shippagan (NB) Canada E8S 1J2
I
n Alaska, bone meal made in the same processing plants as (co-produced with) fishmeal contains 30 to 45% proteins depending on processing methods. The goal of this project was to develop a cost-effective large-scale method to extract proteins
from fish bone. Clean whitefish bones (with 33% protein) were collected at a local fishmeal company and stored at 4 oC until
processing. The bones were finely grounded in a Wiley Mill using a 2 mm screen. Sixty liters of water purified by reverse osmosis was added to a large steam kettle and heated to ~80 oC. 20 kg of bones were slowly added to the hot water with constant
mixing. Temperature was maintained between 80 to 90 oC. After 25 minutes of mixing, the steam heat was turned off and the
mixture allowed to settle for 90 minutes. At the end of this interval, the mixture had separated into an upper cloudy water phase
(soluble proteins), a middle brown phase (mostly proteins), and a lower white phase (mostly minerals). The upper aqueous
phase was removed by decantation and the middle phase was carefully removed with a large spatula. The lower phase was
discarted. In total, nine batches of bone protein extractions were done. The upper and middle phases were combined and dried
in a Littleford vacuum dryer (Model FM 130-0) for about 5 hours. Since a minimum amount of material is needed in the Littleford
to function adequately, batches 1-3, 4-6, and 7-9 were pooled together for the final drying. Several other methods, including
acid/base solubilization and/or hydrolysation, were tested for their ability to efficiently extract bone proteins and were successful in producing small amounts of material. However, they failed to produce pilot-scale amount of product. These methods
will be described and we will discuss why they proved to be ineffective. We will also present the results of proximate analysis,
amino acids, mineral, lipid classes, fatty acid analysis that were performed on the extracted protein fractions produced at pilot
plant scale.
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Advances in processes and added value of products
P-55
Determination of shelf life in fried and boiled
whole frog meat stored in refrigerator
Cakli S., Kisla D., Cadun A.*, Dincer T., Caglak E.
Ege University, Faculty of Fisheries, Department of Fishery and Fish Processing Technology, 35100 Bornova, Izmir, Turkey
T
he comparative study was conducted on the effects of cooking methods in whole frog’s meat. Two selected cooking methods
were used and the samples were stored in the refrigerator (-1.20 ± 2.01) oC for determining shelf-life. One of the cooking
methods was boiling which gave the better results according to the chemical and sensory analysis. Other cooking method was
frying with using sunflower oil. According to the TBA results the shelf-life of fried and boiled frog was determined as 9 days. TBA
values were achieved as 10.60 ± 0.12 (mg malonaldehyte/kg) for fried samples and 8.16 ± 0.57 for boiled samples. Both samples lost their brightness according to the color measurements. Texture analysis (TPA) showed us the differences in between
both lot. According to the microbiological analysis, frog meat cooked by either frying or boiling was found shelf-life stable after
15 days storage.
Methodology
Frozen Rana esculentus which was skinned, headless and gutted were divided into two lots, for frying (A) and for boiling (B).
They were both thawed in the refrigerator for 18 hours.
Fried samples were covered with pasting and coating materials before frying operation. Samples were fried using sunflower oil
for 15 minutes. After then they were placed in a pan for cooling. Samples were placed in polystyrene plates and covered with
stretch films. On the other hand group B was boiled for 20 minutes in a stewpot. After then they were cooled to the room temperature. Samples were placed in polystyrene plates and covered with stretch films. Groups were both stored in refrigerator.
Analysis
Moisture, ash and total lipid were determined as proximate analysis. Total volatile basic nitrogen (TVB-N) (Vyncke, 1996).
Thiobarbituric acid (TBA) (Tarladgis et al, 1960), pH value were determined as chemical analysis. Color measurement was
carried out with spectro pen using method of Schubring (2002). Texture measurement was performed as instrumental texture
profile analysis using a SMS Texture analyser TA.XTPlus according to Schubring (2001). The texture parameters hardness,
chewiness, resilience and cohesiveness, springiness, adhesiveness, elasticity were estimated by double compression of the
sample. Cook loss of whole frog was determined. Sensory evaulation was performed.
Microbiological Analysis
Psychrotrophic bacteria count (Ariyapitipun et al., 1999) and yeast-mold count (Leroi et al., 1996) were determined in fried and
boiled frog meat for microbiological analysis.
Results
As a comparison of two selected cooking method, whole frog meat cooked by either frying or boiling which were stored in the
refrigerator were analyzed for determining the differences of shelf life. According to the TBA results, the shelf life of fried and
boiled frog meat were determined as 9 days although both sample groups were found shelf-life stable after 15 days. TBA values
were determined as 10.60 ± 0.12 for fried samples and 8.16 ± 0.57 for boiled samples.
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Advances in processes and added value of products
P-1
Drench curing of Atlantic salmon (Salmo salar) fillets
with smoke condensate - an alternative processing
technology in the production of smoked products
Birkeland S.*, Skåra T.
Norconserv AS Seafood Processing Research, Niels Juelsgate 50, P.O. Box 327, Stavanger, Norway N-4002
S
moke condensates (SC) are frequently used in Norway inthe production of food items such as sausages and cured ham.
On the contrary, in the salmon industry the use of SC in the production of smoked fillets is absent.
The aim of this study was to investigate the suitability of using a smoke condensate protocol (SCP) in the production of smoked
fillets, as compared to fillets smoked with a wood chips protocol (WCP), with respect to important quality attributes such as
surface color parameters, texture, microbiology, exudates in vacuum-packages during storage, processing yield, water activity,
sensorial parameters and content of benzo(a)pyrene.
The SCP included dry salting (18 h, 3-4 °C),drenching of fillets in an aqueous solution of SC (1 min, 1:3 volume ratio, Salmon
Smoke, Red Arrow Products Company LLC, Manitowoc, WI, US) and drying (150 min, chamber temp; 28 °C, relative humidity;
45%, air velocity; 1.0-1.5 m×s-1). The WCP included dry salting (18 h, 3-4°C), drying and smoking (drying; 180 min,smoking;
300 min, chamber temp; 22 °C,relative humidity; 49%, air velocity 0.4-0.8 m×s-1).
The fillets processed with the SCP were significantly less red (a*), lessfirm and had a higher processing yield than the WCP
fillets. Sensorial evaluation (color, taste, aroma and texture) of the products revealed only small differences between the SCP
and WCP fillets where the most pronounced differences observed were in the parameters firmness, juiciness and smoke level.
Microbiological parameters aerobic plate count (APC), psychrotropic bacteria (PB) and lactic acid bacteria (LAB) were low and
not different between the differently processed fillets after chilled storage (3-4 °C) for 7-38 days. No difference in the amount of
exudates during vacuum storage and the level of benzo(a)pyrene were observed between SCP and WCP fillets.
The use of drenching technology with smoke condensate seems well suited for production of cold-smoked salmon, although
the processors have to optimize the processing conditions during the drying step and adjust the smoke condensate formulation
according to their product specifications.
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Advances in processes and added value of products
P-49
Effects of different thawing methods on the freshness quality
in gilthead seabream, sardine, anchovy and black mussel
Dincer T.*, Cadun A., Cakli S., Tolasa S.
Ege University, Faculty of Fisheries, Department of Fishery and Fish Processing Technology, 35100 Bornova, Izmir, Turkey Objective
T
he comparative study on effects of thawing methods on quality of three fish species and 1 mussel specie was done. Chemical quality analysis and sensorial quality methods were used to determined the differences in different thawing methods.
The frozen samples were thawed by three methods, representing slow (refrigeration), moderately fast ( tap water) and fast
(microwave ) thawing modes. Microwave thawing method gave the best results for anchovy, in term of chemical and sensorial
quality of thawed samples. On the other hand in mussel, sardine and gilthead sea bream, slow method (refrigeration) gave the
best results according to chemical and sensory analysis.
Methodology
Three selected of frozen fish species and 1 mussel specie were thawed by three methods, representing slow (refrigeration), moderately fast ( tap water) and fast (microwave ) thawing modes. The samples were sardine (Sardina pilchardus),
gilthead seabream (Sparus aurata), anchovy (Engraulis encrasicolus L. 1758) and black mussel (Mytilus galloprovincialis).
In group A, approximately 1 kgs of gilthead see bream, anchovy, sardine and mussel from frozen sample were transferred to
a 2.18 ± 2.25 oC refrigerator and allowed to thaw slowly for 24 h. In group B another samples from same species and same
amounts were put in a plastic pan with running tap water (17.2 oC) for 24 min to achieve an intermediate thawing rate. The flow
rate of water was maintained low to avoid agitation. The temperature at the centre of the thawed gilthead sea bream, anchovy,
sardine and mussel were measured with a thermocouple, which were 19.2 oC. In the group C rapid thawing method was used.
Different 1 kg of samples from same species were thawed using a microwave oven (defrost mode in 15 minutes).
Analysis
Trimethylamine (TMA) analysis was carried out according to the method proposed by (AOAC, 1984). Total volatile basic nitrogen (TVB-N) was determined according to the method of Vyncke (1996). Thiobarbituric acid (TBA) was determined according
to the method proposed by Tarladgis et al. (1960). The pH value was recorded using a pH meter (HANNA model Microprocessor), the glass electrode being applied directly to the fish flesh. And color measurement was carried out with Dr Lange model
spectro pen by using Schubring (2002). And the cook loss values were determined by the method using 90 oC in 10 minutes.
And sensorial evolution was performed.
Results
Microwave thawing method gave the best results for anchovy, in term of chemical and sensorial quality of thawed samples.
On the other hand in mussel, sardine and gilthead sea bream, slow method (refrigeration) gave the best results according to
chemical and sensory analysis. And also color measurements were supported to the sensorial results.
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
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Advances in processes and added value of products
P-47
Effects of phosphates treatment on the
quality of frozen-thawed fish species
Kilinc B., Cakli S., Dincer T.*, Cadun A.
Ege University, Faculty of Fisheries, Department of Fishery and Fish Processing Technology, 35100 Bornova, Izmir, Turkey Objective
T
he influence of dipping different types of phosphate solutions on microbiological, chemical, colour and textural quality of
different fish species (saith, gilthead sea bream, calamari and anchovy) were assessed. The purpose of the present study
was to evaluate quality attributes of frozen-thawed fish species treated with monopotassium phosphate (MKP), monosodium
phosphate (SPP), sodium pyrophosphate (SPP), trisodium phosphate (TSP), sodium tripolyphosphate (STPP) and also improve the quality of frozen-thawed fish species.
Methodology
Frozen species were dipped in to the phosphate solutions after they were thawed . 5 phosphate group were used as follows;
for 10 min in 5-10% solutions containing monopotassium phosphate (MKP), monosodium phosphate (SPP), sodium pyrophosphate (SPP), trisodium phosphate ( TSP), sodium tripolyphosphate (STPP) and one salt group. The frozen samples were
thawed by representing slow (refrigeration) thawing mode.
Analysis
Total viable and psychrotrophic bacteria counts were determined by the pour plate method, using Plate Count Agar (Difco, 047917) as the medium. Plates were incubated at 30 ºC for 24-48 h and 7 ºC for 10 days respectively (Harrigan & McCance,1976).
Lactic acid bacteria count was determined by using pour plate method using MRSA ( LAB M 93) as the medium. Plates were
incubated at 30 ºC for 3-5 days (Dalgaard & Jorgensen, 1998). Enterobacteriaceae were determined as pour plate method in
Violet Red Bile Glucose Agar (VRBGA, Oxoid CM 485) after 24 h incubation at 37 ºC (Debevere and Boskou, 1996).
Trimethylamine (TMA) analysis was carried out according to the method proposed by (AOAC, 1984). Total volatile basic nitrogen (TVB-N) was determined according to the method of Vyncke, (1996). Thiobarbituric acid (TBA) was determined according
to the method proposed by Tarladgis et al (1960). The pH value was recorded using a pH meter (HANNA model Microprocessor), the glass electrode being applied directly to the fish flesh. And color measurement was carried out with Dr Lange model
spectro pen by using Schubring, (2002). And the cook loss values were determined by the method using 90 oC in 10 minutes.
Results
Dipping frozen-thawed fish species in 5-10% phosphates improved the quality while compared with control group. Addition of
phosphates to frozen -thawed fish species reduced the drip loss and inhibited the the bacteria. Phosphate treatment can be an
alternative way to improve the quality of frozen-thawed fish.
134
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
Advances in processes and added value of products
P-9
Electrohydrodynamic (EHD) drying of fish
Baron R., Cardinal M., Cornet J., Gigout F., Leroi F.*
IFREMER Departement Sciences et Techniques Alimentaires Marines
A
n important part of all the energy is used for the drying of products in industry. An efficient drying technique has thus become an important issue in energy utilization and conservation. This fact is also true for seafood industry. The drying technique using electrohydrodynamics (EHD), receives little attention even if this technique uses small electric power as compared of
conventional drying techniques. Some researchers have studied the effect of corona electrode on drying ofpotato slabs (Chen,
Barthakur, 1994), apple slices (Hashinaga, Bajgai, Isobe, Barthakur, 1999) or wheat (Cao,Nishiyama, Koide, 2002).
The objectives of present study were to investigate the potential of EHD drying of fish (salmon and saithe), and on sensorial and
sanitary point of view. The feasibility study was based on an experimental adaptation of an industrial air-conditionned dryingsmoking kiln. EHD drying on agar gels poured in Petri dishes was also performed to evaluate this model and to optimise the
EHD process and to check easily its effect on microorganisms. Different agar concentration and volume in Petri dishes were
tested. Finally, plates poured with 40 ml of BHI broth with 1.5% of agar were retained as good model. For similar thickness,
the kinetics of drying with or without electro-hydrodynamic effect are comparable on Petri dish and on fish (slightly faster on
Petri dishes). The primary mechanism for EHD drying is the corona wind produced by applying a sufficiently high voltage to an
electrode with a small radius of curvature. Air in the vicinity of the electrode surface is ionised and propelled toward the opposite
electrode at high velocities. As the ions travel, they collide with neutral gas molecules and momentum exchange takes place
between them. This phenomena create the ion-drag flow, also called the corona (or ionic) wind. Since corona discharge occurs
at room temperature and atmospheric pressure, this makes EHD dryingparticularly attractive for low temperature applications
and fish is a good candidate for this technique. The experiments carried out will be described.
Two kinds of geometry of electrodes were evaluated (points to plate electrodes and wires to plate electrodes). Drying was
performed in an air-conditioned kiln for a temperature of 24 ± 1 °C, a relative hygrometry of 65 ± 4% and an global average
air velocity around the product of 1 ± 0,4 m/s. Somefishes or agar gels were laid out between two electrodes, others used as
on a grid located at 20 cm below the products between electrodes. Voltage, applied between the two electrodes, is adjusted
to create corona discharge conditions. Positive and negative polarity were tested for agar gels. For the dryingphase and with
a specific geometry of discharge electrode (points to plate), the kinetics of the waterloss of fish (saithe, truits and atlantic salmon) will be first analysed at different voltages. After two hours of processing and for all species and for high voltage, a ratio of
1,75 ± 0,2 between weight loss with electrostatic effect on weight loss without electrostatic effect is observed. A more intensive
drying is measured with agar gels, but with the same order of magnitude for the ratio.
A microbial preliminary study on agar gels with some specific inoculated flores (Serratia liquefaciens and Carnobacterium
piscicola) shows the interest of the EHD (electro hydrodynamic drying) for limitation of the growth especially for Serratia liquefaciens (even if the difference neeeds to be further confirmed). A sensorial test (triangular test) on saithe will be discussed on
this presentation.
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Advances in processes and added value of products
P-54
Extraction of coenzyme Q10 from mackerel and
herring by-products with various mild processes
Laplante S.1,2, Souchet N.1,2, Bryl P.2*
1. Université du Québec à Rimouski (UQAR), Rimouski (QC) Canada
2. Centre Technologique des produits aquatiques (CTPA), Gaspé (QC) Canada G4X 2V6
A
mong the fat fish species available from Eastern Quebec (Canada), the whole mackerel (Scomber scombrus) and herring
(Clupea harengus) represent abundant sources of fishery by-products (around 1000 tons per year) that are actually underutilized. This is why we compared various mild extraction processes (supercritical CO2 extraction, conventional oil extraction
from proteolytic hydrolysates) for the recovery of CoQ10 from those by-products. With the CO2 extraction process, by-products
were used as lyophilisates. From both processes, the yields of oil extracted from mackerel were higher, but higher concentrations of CoQ10 were obtained from herring oil extracts. With supercritical CO2 extraction process, the increase of CO2 flow from
600 to 3000 g•h-1 increased both the yield of oil extracted and its concentration in CoQ10. Moreover, with mackerel, the use of
ethanol as cosolvent increased the yield of oil extracted and also its concentration in CoQ10. Those results will be discussed in
a view of optimizing and scaling-up the recovery of CoQ10 in oils extracted from mackerel and herring by-products.
136
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Advances in processes and added value of products
P-4
Fractionation of a saithe (Pollachius virens) hydrolysate
using SEC-FPLC: Influence of peptide size on antioxidant properties
Chabeaud A.1,2*, Guérard F.1, Vandanjon L.2, Bourseau P.2
1. ANTIOX, Laboratory, Université de Bretagne Occidentale Quimper, France
2. LET2E, Laboratory, EA3373, Université de Bretagne Sud, Lorient, France
P
roduction of fish protein hydrolysates by proteinase treatment is a means to transform by-products into new products with
improved functional and biological properties. In recent years, a large number of hydrolysates exhibiting hormonal, growth
stimulatory, immuno-modulatory functions, anti-hypertensive and antioxidant effects have been generated from fishery by-products.
We are currently investigating the production of a saithe hydrolysate having antioxidant and DPPH° radical scavenging properties by a two-step process including enzymatic hydrolysis and membrane separation.
This study focuses on the analytical fractionation of a saithe hydrolysate using size exclusion chromatography (SEC-FPLC) to
determine the influence of peptides size on antioxidant properties, with the aim to develop suitable strategies for membrane
fractionation.
Enzymatic hydrolysis of saithe (Pollachius virens) proteins by Alcalase® 2.4L was carried out in a 1L-batch reactor at 60 °C,
pH 8, enzyme/substrate ratio = 2,3%. The resulting hydrolysate was fractionated using size exclusion chromatography (Superdex Peptide, Amersham). Collection times are fixed at 19, 23, 28 and 33 min corresponding to 7000, 3000, 1000 and 500 Da
respectively, according to the calibration curve of the column. The antioxidant activity (â-carotene test) and the DPPH° radical
scavenging effect of the four collected fractions were measured. Fractionation induces decrease of antioxidant activity, showing
either a synergic effect of bioactive peptides or artifacts in experiments. However, the same global influence of peptide size on
antioxidant and scavenging properties is observed: smaller the peptides are, higher the activity of the fraction is.
Future works will concern additional chromatographic analyses of the active peptides (ion-exchange) and fractionation of the
hydrolysate using membrane processes (nano- and ultrafiltration) with the aim to improve their specific activities.
This investigation was supported by Région Bretagne, France (PRIR, « Activemb ») and by the IP 6th FP European Program
SEAFOODplus.
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Advances in processes and added value of products
P-46
Grading of pink salmon skin watermarking
using a machine vision system
Oliveira A.C.M.1*, Crapo C.1, Balaban M.2
1. Fishery Industrial Technology Center, University of Alaska, Fairbanks School of Fisheries & Ocean Sciences, Kodiak, Alaska USA
2. Department of Food Science and Human Nutrition, University of Florida, Gainesville, Florida USA, 32611
S
almon fisheries contribute significantly to Alaska’s economy. During the past three years, pink salmon catches ranged
between 165,000 to 250,000 T/year. Salmon are anadromous and undergo drastic physiological and biochemical changes
during spawning migration. Fish do not feed after entering fresh water, and metabolic degeneration occurs as they approach
full sexual maturity. Changes such as migration of lipid soluble pigments from the muscle into the skin and gonads, increase in
flesh pH, and decrease in protein and lipid content have been observed. Muscle quality is greatly impacted by these biochemical changes and late-run salmon often have less desirable texture and flavor. Pigment migration is the cause of skin watermarking and becomes progressively pronounced with the approach of sexual maturity and subsequent spawning. Therefore, wild
salmon species in Alaska are often graded according to the degree of skin watermarking based on the guidelines suggested
by the Alaska Seafood Marketing Institute Color Evaluation Guide for Pacific Salmon (I and II).
Watermarking is visually inspected; however the large number of ASMI watermarking grades, combined with a large natural
variability cause difficulties during sorting. Computer vision systems have been successfully applied to measure quality of
seafood such as shrimp, oysters, sturgeon, tilapia and catfish, with the ability of determining L*a*b* values for each pixel of
the sample’s image. The entire surface of the food is analyzed and average values can be determined. Machine vision is also
capable of identifying and quantifying all colors present in a sample. Our goal was to test the ability of a machine vision system
to sort pink salmon according to its degree of skin watermarking.
Ninety fresh pink salmon with various degrees of skin watermarking (AB, CD, DE, E and F) were procured from a processor in
Kodiak. Fish were graded by two experts and images were taken using a machine vision system consisting of a light box, and a
digital firewire camera connected to a personal computer. Software that we developed controlled the camera settings, captured
images and analyzed them. First, average L*a*b* values were determined for the entire fish skin surface. The variability in the
samples prevented accurate classification of fish into the 5 grades. Next, a rectangular «region of interest» (ROI) was selected
for each fish. The rectangle was bounded by the lateral line at the top, the end of the dorsal fin at the back, just the back of the
gill plate at the front, and the level of pectoral fin at the bottom. The average L*a*b* values of the ROI were calculated. However, natural variability again prevented accurate classification of fish. Finally, within the ROI, all the pixels with an L* value less
than 80 were counted, and their percentage to the total number of ROI pixels were taken. This parameter (range 0 to 100%)
accurately classified salmon by watermarking, and found errors in judgement of experts in a few cases.
Percent of the described ROI with L*<80 can be used to automate the classification of whole pink salmon by watermarking.
138
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P-13
Improved quality of frozen herring
by a new processing line
Storteig C.*
Bodø University College, Norway
N
owadays the largest fishing grounds for herring is Vestfjorden in North Norway, and the market for high quality frozen
herring has increased. Due to the handling of large quantities of herring, a factory in Bodø has been rebuilt for faster processing of the fish.
Only fishing boats with a written record of the freshness and temperature in the cargo are allowed to deliver herring to this factory. They can process 70 tons per hour and the total processing time is only a couple of hours. The temperature in the herring
is always below 5 ºC before freezing. This factory is producing skin on butterfly fillets, round herring and sometimes skinless
single fillets, all packed in 20 kg’s boxes. The boxes with herring are frozen in a freeze blast tunnel with an air temperature of
-43 ºC, and after 18 hours the herring is transfered to a freeze storage room. Generally it is accepted, that the storage time for
a high quality herring products is only 3 months at -20 ºC, and longer storage time can only be achieved by using lower storage
temperature. This experiment was performed to compare the quality of skin on butterfly fillets stored at -20 ºC and -40 ºC.
Up to 6 months storage the quality changes was minor. There was not developed any brown colour, neither any rancid odour
nor any rancid taste.
The demands for a high quality raw material, rapid processing and rapid freezing seems to be more important factors for maintaining the quality of the product than the following freeze storage temperature.
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P-44
Influence of the thawing and salting method on
sensory characteristics of dry-cured tuna loins
Barat J. M.*, Aguilar J., Grau R.
IU-IAD Departamento de Tecnología de Alimentos, Universidad Politécnica de Valencia, Valencia, Spain
T
he aim of this work was to compare the sensory characteristics of dry-cured tuna loins obtained from frozen raw material
traditionally processed (thawed in a cold chamber and dry salted) with dry-cured tuna obtained by applying simultaneously
thawing and salting procedure.
A total of 15 frozen loins were used in the study with an average weight of 1782 ± 383 g. Three thawing/salting procedures
were used in the study; thawing the samples by air and subsequent dry salting (ATDS), thawing and salting the samples simultaneously by stacking them in solid salt (STDS), and finally by dipping the samples in saturated brine without stirring (BTS). All
experiments were done at 3/-1 ºC.
Salted tuna loins were dried at 65% relative humidity and 15 ºC. The drying period ended when sample moisture was close to
50% (w/w). Moisture, fat and sodium chloride determinations were carried out on the dry-cured samples, and compared with
the predicted values from results obtained in a previous work. A sensory analysis was performed in order to compare the effect
of the thawing and salting method on appearance, odor, color, flavor and overall liking. This analysis was carried out by a panel of one hundred non-trained assessors, all of them familiar with dry-cured tuna loins by using a hedonic scale from 1 (very
unpleasant) to 5 (very pleasant). Additionally the obtained samples were compared with commercial ones.
The obtained results indicate small differences among samples, whatever the thawing and salting process employed. This
implies that the new simultaneously thawing and salting procedures can be used to produce this cured fish product with clear
reduction in processing time, cost and environmental impact.
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P-39
Multi-step urea fractionation of marine oils: production of fractions
high in saturated, monounsaturated or polyunsaturated fatty acids
Tian Z.1*, Bryl P.2, Carbonneau M.-É.2, Arul J.1, Garro J.M.3, Angers P.1
1. Department of Food Science and Nutrition, Université Laval, Québec (QC) Canada G1K 7P4
2. Centre technologique des produits aquatiques 96, montée de Sandy Beach, Gaspé (QC) Canada G4X 2V6
3. Naturia inc., 4220, rue Garlock, Sherbrooke (QC) Canada J1L 2P4
D
iverse fatty acid fractions-saturated fatty acids (SA), monounsaturated fatty acids (MUFA) and long chain polyunsaturated fatty acids (PUFA), including eicosapentaenoic acid (EPA), docosapentaenoic acid (DPA) and docosahexaenoic acid
(DHA) derived from chemically hydrolyzed marine oils (mackerel, seal and herring oils) were concentrated by multi-step urea
fractionation method using methanol as the solvent. The effects of urea/fatty acids/methanol ratio, crystallization temperature
and multi-step procedure on the final products were collectively studied to optimize the preparation conditions. Data on fatty
acid composition indicate that multistep urea fractionation is an efficient method to separate marine oils fractions and produce
highly purified SA, MUFA and PUFA. After complexation of SA and low unsaturation free fatty acid, concentrations (Cm) of
PUFA up to 94.7% and 90.2%, were obtained from mackerel oil and seal oil respectively with FFA:Urea:Methanol ratio from
3:1:5 to 4:2:12 (w/w/v) at 4 °C. The complexed crystals were enriched with SA and MUFA. Cm values for SA up to 70.0% and
53.7% were obtained with FFA:Urea:Methanol ratio from 1:3:10 to 3:5:20 (w/w/v) at 4 °C; while a two-step fractionation was
required to obtain the Cm values for MUFA up to 61.1% and 76.6%, respectively for mackerel and seal oils, with FFA:Urea:
Methanol ratio from 2:1:5 to 3:2:10 at 4 °C.
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P-19
Preservation methods for retaining n-3 PUFAs in salmon products
Bower C.K.1*, Malemute C.L.1, Oliveira A.C.M.2
1. USDA-ARS, University of Alaska, Fairbanks 360, O’Neill Bldg. Fairbanks, Alaska USA, 99775
2. Fishery Industrial Technology Center, University of Alaska, Fairbanks 118, Trident Way Kodiak, Alaska USA, 99615
B
y-products from Alaska’s fishing industry represent an underutilized resource often subject to disposal costs rather than
economic benefits. In some locations these high-protein discards are preserved as fishmeal, however during this processing, valuable compounds may be lost or diminished. Currently, the demand for salmon oil is increasing, as n-3 long-chain
polyunsaturated fatty acids (PUFA) gain recognition for their health benefits. Oil extraction prior to fishmeal processing is not
always possible. Other techniques exist for preserving salmon, but have not been evaluated for their effectiveness in retaining
the value of salmon oil in by-products. The objective of this research was to explore alternative processing methods that might
prove useful for retaining the maximum quality of high-value n-3 PUFAs in salmon by-products.
In this study, five different processing methods were used to preserve coho salmon (Oncorhynchus kisutch), before evaluating
the fatty acid profiles. Samples were smoked (27 °C, 3 h), pressure-cooked (70 kPa, 2 h), frozen (-20 °C), salted (23 °C), or
pickled (salted for 4 days, then stored in vinegar). All samples were stored for 90-days before analysis. Salmon heads were
also included because of their high oil content. Heads were frozen for 90-days, then cooked in water (100 °C, 0.5 h) before
testing. All lipid extractions were performed using an isopropanol/hexane solvent. Fatty Acid Methyl Esters were prepared and
then analyzed using Gas Chromatography with Flame Ionization Detection.
Total fatty acids (per 100 g of tissue) for smoked samples and pressure-cooked fillets were similar to their untreated controls
(stored at -80 °C). However, salting, freezing, or pickling the fillets decreased the fatty acid content by approximately half. The
highest n-3 PUFA values occurred with smoked and pressure-cooked salmon, which retained 94% of their original n-3 PUFAs
as compared to the control fillet. Freezing, salting, and pickling were less effective at preserving n-3 PUFAs, retaining only
58%, 54%, and 43% (respectively) of their original quantities. Salmon heads were found to contain over 300% more total fatty
acids than the fillets, losing only 15% when heat-processed. The heads also retained over 90% of their n-3 PUFA after cooking.
The results of this study may provide direction for handling and storage of underutilized fish by-products in order to retain the
maximum levels of high-value n-3 long-chain polyunsaturated fatty acids.
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P-15
Pressure induced germination and inactivation of Bacillus cereus
spores in fresh blue crab (Callinectes sapidus) meat
Suklim K., Flick G.*
Food Science and Technology Department, Virginia Tech (0418), Blacksburg, Virginia USA, 24061
P
ressure-induced germination and inactivation of B. cereus (ATCC 14579, ATCC 49064, a crab meat isolate) spores by high
hydrostatic pressures (100, 200, 300, 400, 500, and 550 MPa) at 40 degrees C for 15 min were studied. In sterile distilled
water, spore germination increased with increased pressures; whereas inactivtion decreased with pressure up to 200-300 MPa
and increased with medium to high pressures (300-550 MPa). A pressure of 550 MPa resulted in the maximum germination
and inactivation (3.5-5.5 logs germination and 3-4.5 logs inactivation) among strains studied. Among 3 strains, spores of the
crab meat isolate was found to be the most resistant to germinate and inactivate by pressure. In fresh crab meat, inoculated
B. cereus spores were protected from inactivation by pressure; but its germination was enhanced to a higher degree compared
to spores dispended in distilled water probably due to the presence of some germinants required in the germination process
in addition to pressure. Inoculated fresh crab meat with B. cereus spores treated with high pressure (550 MPa, 40 °C, 15 min)
and stored at 4 and 12 °C for 31 days showed that B. cereus was not a competitve organism with the presence of the other
meat microflora. However, treated crab meat in which some of the pressure-sensitive microflora were inactivated, B. cereus
survived through the end of the 4 °C storage period but was not able to produce diarrheal toxin at a detectable level performed
with Tecra Bacillus Diarrhoeal Entertoxin Visual Immunoassy.
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P-27
Protein and lipid oxidation during frozen storage of rainbow trout
Baron C.P.*, Kjærsgård I., Jessen F., Jacobsen C.
Danish Institute for Fisheries Research, Dept. of Seafood Research, DTU, Building 221 Kgs., Lyngby, Denmark DK-2800
D
uring prolonged frozen storage of fatty fish, lipid oxidation is often believed to be responsible for quality deterioration.
However, some of the quality changes observed during frozen storage cannot solely been attributed to lipid oxidation.
Interaction between protein oxidation and lipid oxidation has not been extensively studied and deserves further attention as it
might explain some of the changes in fish quality.
Rainbow trout fed a diet containing fish oil with either astaxanthin (200 ppm) or without pigment were stored frozen for up to
13 months at -20, -30 or -80 °C. Lipid and protein oxidation were followed in order to reveal interactions between protein and
lipid oxidation but also to investigate the ability of the carotenoid pigment to prevent both protein and lipid oxidation. Lipid oxidation was followed by measuring primary (peroxides values) and secondary oxidation products (volatiles). Protein oxidation was
followed by measuring protein carbonyls and by performing 2D western blotting against protein carbonyls groups. In addition
free fatty acids, tocopherol and astaxanthin content were followed throughout the entire storage period.
Results indicate that oxidation is dependent on storage temperatures and time, the lower temperatures (-30 and -80 °C) inhibiting both lipid and protein oxidation. Results obtained from 2D immunoblots indicate that some proteins are more susceptible to
oxidation than others, but no quantifiable differences were observed in the immunoblots irrespective of the storage temperature
and time. A significant decrease in astaxanthin and tocopherol and an increase in FFA were observed for rainbow trout stored
at -20 °C. However, in our experiment astaxanthin did not seem to have any effect on either lipid or protein oxidation. Further
studies are needed to clarify the kinetics of protein oxidation in fish muscle and it significance for fish quality.
144
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P-23
Proteins, lipids and chitin distribution of enzymatic hydrolysates
fractions from snow crab by-products
Carbonneau M.-É.1*, Bryl P.1, Beaulieu L.1,2, Thibodeau J.1,2, Donovan N.1, Ouellet D.1
1. Centre technologique des produits aquatiques, Gaspé (QC) Canada G4X 2V6
2. Université du Québec à Rimouski, Rimouski (QC) Canada
S
now crab by-products constitute valuable sources of components, such as proteins, lipids and chitin. The aim of this work
was to apply a pilot scale enzymatic hydrolysis followed by fractional operations in order to recover enriched fractions of
these compounds. Enzymatic hydrolysis is a gentle process used as an alternative to chemical or mechanical treatments that
often generate undesirable reactions, which could destroy valuable products and reduce product recovery. Following this process, decantation permits the separation of solid and liquid phases while centrifugation allows the separation of lipids from the
protein solution. Finally, fractionation of proteins and peptides was achieved using micro-filtration, ultra-filtration and reversed
osmosis membrane systems. The chitin was found essentially in the solid phase. The centrifugation step generated an enriched lipid fraction. Also, the resulting protein solution contained few amounts of lipids, which could be removed together with
the high molecular weight proteins by micro-filtration. The lipid classes and the proteins/peptides molecular weight distribution
changed according to the steps of the process. Further investigation could contribute the increased value of bioactive compounds contained in each fraction.
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P-17
Quality changes in Norway lobster (Nephrops norvegicus) tail meat:
the influence of handling time, storage temperature and hygiene
Neil D.M.1, Albalat A.1, Gornik S.1*, McPherson H.1, Westrop G.1,
Atkinson R.J.A.2, Birkbeck T.H.1, Coombs G.H.1
1. Institute of Biomedical and Life Sciences, University of Glasgow, Glasgow G12 8QQ, Scotland, United Kingdom
2. University Marine Biological Station (UMBS), Millport Isle of Cumbrae, Scotland, United Kingdom
T
he fishery for Norway lobsters (Nephrops norvegicus) is the most valuable in Scotland, with a TAC of more then 40.000t
and an export value of more than £170M. The animals are sold either as frozen tails, as whole animals (fresh or frozen) or
live animals.
Currently, best practice guidelines for day-boats supplying Nephrops tails recommend immediate tailing (separation of the tail
from the inedible head), washing and shielding from the elements, but not necessarily icing. Only on trips of more than 18h and
during storage and transport are icing and/or chilling recommended. In comparison to the white fish industry these guidelines
and practices seem very lax.
This project has simulated different possible practices on board a trawl vessel in order to understand and analyse the quality
deterioration in Nephrops tails that can take place during a fishing trip and post-harvest storage. The time between landing the
catch and icing was varied, and different temperatures were imposed over this time. Using the same protocol, the importance
of handling hygiene was studied by comparing thoroughly-washed and unwashed product.
The quality of tail meat was assessed using a series of microbiological and biochemical methods. Total viable counts were used
to reflect the sample bacterial load. The accumulation of secondary spoilage products, such as trimethylamine (TMA), ammonia
and aldehydes (TBARS) was measured, and the pH of the samples was also monitored. The concentrations of ATP breakdown
products were determined by HPLC, and the changes in freshness were calculated using the K-value.
The results show that although there is a time window in which the Nephrops tails can be handled, both the time to icing and
the storage temperature are crucial factors for maintaining a good quality product. The pH is also temperature-dependent, but
eventually increases in all samples. Furthermore, if the tails are not cleaned properly before icing then their quality deteriorates
rapidly, even when they are held on ice. The freshness, reflected by the k-value, is influenced more by storage temperature
than by handling hygiene and bacterial load, and is maintained best under immediate and permanent icing.
A major next step in this project is to involve a professional sensory panel to compare and evaluate the results from our objective assays with organoleptical perceptions (taste, appearance and odour).
This work was supported by a grant from the EU Financial Instrument for Fisheries Guidance (FIFG) Scheme through the
Scottish Executive, and by Young’s Bluecrest Seafoods Ltd.
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P-25
Quantification of ammonia, MMA, DMA, TMA and TMAO
in fish processing by-products from different cold water
marine species by capillary electrophoresis
Wu T.H.*, Bechtel P.J.
Agricultural Research Service, U.S.D.A., 245, O’Neill Building, University of Alaska-Fairbanks, Fairbanks, Alaska USA, 99775
D
eterminations of the total volatile base nitrogen (TVB-N) are routinely used to evaluate fish quality. TVB-N consists of ammonia, monomethylamine (MMA), dimethylamine (DMA), and trimethylamine (TMA), the levels of which are altered during
spoilage by bacterial or enzymic degradation of trimethylamine oxide (TMAO). The levels of TVB-N and TMAO are different for
each fish species and further differentiated within the various fish parts. In addition, TVB-N and TMAO are altered by the type of
processing and time of storage. TVB-N levels have been routinely measured in fish muscles during ice storage; however, little
is known about the distribution of the individual constituents in other fish parts. As the utilization of fish processing by-products
increases and higher value products are produced, levels of TVB-N and TMAO become of increasing importance as a quality
characteristic.
A quick and sensitive capillary electrophoretic method slightly modified from Timm and Jørgensen (2002) was used to simultaneously determine the levels of ammonia, MMA, DMA, TMA and TMAO in aqueous extracts from a variety of materials made
from fish processing by-products. The instrument used was an Agilent capillary electrophoresis system equipped with a buffer
replenishment system, UV/VIS diode array detector, Chem Station software, auto sampler and Agilent fused silica capillary
with extended light path. Detection was made in the indirect mode by measuring the difference in absorbance at 310 nm and
215 nm for the separated compounds. Aqueous extracts were analyzed from fish by-products of several cold water fish species
and included heads, viscera frames, whole fish, milt and roe. In addition, bone meal, liver meal, fish meal and freeze dried
stickwater were analyzed.
TVB-N ranged from 1.46 ± 0.45 mg/kg (n=3) in black cod heads to 157.75 ± 23.47 mg/kg (n=3) in freeze-dried stickwater
from red salmon. Ammonia was present in 100% of the samples, ranging from 1.46 ± 0.45 mg/kg (n=3) in black cod heads to
128.10 ± 13.65 mg/kg (n=3) in freeze-dried stickwater from red salmon. MMA was not detected in any of the samples. DMA and
TMA were detected in 39% and 32% of the samples and TMAO was detected in 79% of the samples. The results suggested
there is a wide distribution on the levels of TVB-N and TMAO in the materials tested. Lower levels of TMAO were detected in
viscera samples in comparison to the other fish by-products; which suggested that the bacterial or enzyme make-up within
viscera is degrading TMAO. Lower levels of TMAO in fish meal may indicate decomposition of TMAO or fractionation into the
stickwater during processing.
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P-21
Recovery of proteins from
pearl production waste
Zhou H., Liu S.*
College of Food Science and Technology Shanghai Fisheries, University 334, Jungong Road, Shanghai, China 200090
H
yriopsis cumingii is a freshwater clam that is widely cultured in China for pearl production. The mantle and meat of the clam
contain high levels of proteins (54% in meat and 41% in mantle) but are usually discarded after pearls are harvested. This
study developed a procedure for recovering proteins from mantle and meat of Hyriopsis cumingii using a pH shift technique and
determined the composition of proteins recovered form the unutilized waste. The protein recovery procedure, which involves an
initial extraction with five volumes of alkaline water (pH 11) at 20 ºC for 1 h followed by a precipitation process with HCl solution
until the isoelectric point of the protein ( pH 5.2) at 20 ºC, was capable of recovering 79% of proteins in the waste products.
Proteins recovered from Hyriopsis cumingii contain high levels of essential amino acids (43%) with serine (10%) being the most
abundant followed by lysine (7%). When compared with soybean proteins, proteins isolated from Hyriopsis cumingii showed
better solubility, water-absorbing ability and emulsion stability. These results suggest that proteins isolated from Hyriposis
cumingii have high nutritional values and might be utilized as food ingredients for the food industries.
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P-34
Seasonal variation in the chemical components of brown algae
in Quebec: Fucus vesiculosus and Ascophyllum nodosum
Kim K.-T.1*, Turgeon S. L.1, Boulanger R.2
1.Institut des nutraceutiques et des aliments fonctionnels Faculté des sciences de l’agriculture et de l’alimentation Université Laval Québec,
QC, Canada G1K 7P4
2.Océanova Biotechnologies, 2, St-Germain Est, Rimouski (QC) Canada G5L 8T7
F
ucus vesiculosus and Ascophyllum nodosum are brown algae that are found in Eastern Canada. These algae contain a lot
of functional elements as polysaccharides, proteins and minerals and their quantity are dependent on the season. Normally,
the maximal quantities of known functional elements (polysaccharides and phenols) are related to the period of algae growth,
so algae are harvested in the winter. But, in Eastern Canada, this in not feasible due to the freezing river. Therefore, the information on the relation between algae elements and season are necessary for an efficient utilization of algae.
This research was achieved to optimize the utilization of brown algae in Quebec. Samples of Fucus vesiculosus and Ascophyllum nodosum were harvested at Bas-St-Laurent River from spring to the fall for 3 years and analyzed for their chemical
composition. The average chemical composition of Fucus vesiculosus were 10.38% of crude protein, 1.56% of lipid, 25.02% of
ash and 62.60% of polysaccharide, while Ascophyllum nodosum contained 8.35% of crude protein, 1.51% of lipid, 19.95% of
ash and 69.54% of polysaccharide. In both algae, the minimum proportion of the crude protein and the lipid were shown in the
summer. The variation of the crude protein and the lipid was dependent reversely on the temperature. The change pattern of
the ash and the polysaccharide did not have any correlation with the temperature and were different in both algae. However, the
inverse proportion was found between the ash and the polysaccharide. The general fucoidan quantity was 3.06 ± 0.04% and
3.07 ± 0.25 in Fucus vesiculosus and Ascophyllum nodosum. The fucoidan quantity was similar in both algae, but the variation
with the season was different.
The next step is to study the influence of season on the biological activity of fucan and polyphenol fractions.
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P-43
Sensory and physicochemical evaluation of smoked sea bass with sodium
replacement
Fuentes A., Fernández-Segovia I., Serra J.A., Barat J.M.*
IU-IAD Departamento de Tecnología de Alimentos, Universidad Politénica de Valencia, Valencia, Spain
T
he aim of this study was to determine the maximum proportion of NaCl that could be replaced with KCl, without affecting
the typical sensory features of smoked sea bass, and to analyze the effect of this sodium partial replacement on the physicochemical quality of the product.
Four salt mixtures (100% NaCl, 75% NaCl–25% KCl, 50% NaCl–50% KCl, 25% NaCl–75% KCl), were used in the salting
stage. The salted samples were smoked by pulverizing the fillets with a liquid smoke solution during 30 s and, finally dried at
35 ºC with a relative humidity of 65% for 3 h. A sensory analysis was performed in order to select the proportion of sodium to
replace in smoked sea bass. This analysis was carried out by a panel of fifty non-trained assessors, all of them familiar with
smoked fish products.Appearance, odor, color, flavor and overall liking were evaluated by using a hedonic scale from 1 (very
unpleasant) to 5 (very pleasant). Analyses of moisture, Aw, pH, water holding capacity (WHC), as well as chloride, sodium,
potassium and magnesium contents, and determinations of color and texture (TPA and shear test), were carried out only in
samples salted with 100% NaCl and in samples salted with the mixture selected in the sensory evaluation.
Replacements of NaCl with KCl did not imply any differences in the appearance, odor and color of samples, in any case. However, sensory analysis showed that in samples with levels of substitution above 50%, the flavor and overall liking scores were
lower. Since sensory characteristics were not affected when the level of sodium replacement was equal or lower than 50%, it
was estimated that the optimum mixture for the study would be 50% NaCl-50% KCl.
The rest of the study was performed in smoked sea bass with 100% NaCl and in samples with 50% NaCl–50% KCl. No significant differences in moisture, Aw or WHC were found between samples; however, pH in samples with 100% NaCl (6.34 ± 0.07)
was slightly higher than samples without substitution (6.19 ± 0.05). Although the sodium replacement could provoke changes
in the color of the samples, no significant differences were observed in this parameter, due to the pulverization with liquid
smoke, which leads to homogeneous color of the samples. Among all the parameters obtained in TPA and shear test, only
gumminess was statistically different between the two samples, being this value higher in fillets salted with 100% NaCl.
It can be concluded that the substitution of 50% NaCl for KCl in smoked seabass does not affect the sensory and physicochemical quality of this product, in addition to be in line with the new tendencies in the tastes of health-conscious consumers.
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P-32
Sonication-assisted deproteination of shrimp shells
Duval F.1*, Atifi S.1, Belkacemi, K.1, Adambounou L.2, Arul J.1
1. Institute of Nutraceuticals and Functional Foods, Department of Food Science and Nutrition, Université Laval, Québec (QC) Canada G1K
7P4
2. Department of biology, chemistry and health sciences, UQAR, Campus de Rimouski, Rimouski (QC) Canada G5L 3A1
C
hitin is the second most abundant natural polymer after cellulose, and is the major structural component of the exoskeleton of invertebrates and cell walls of fungi. Chitosan, the deacetylated form of chitin, exhibits many biological activities
including antifungal, antibacterial properties, elicitation of plant defence reactions, wound-healing properties, tumour inhibition
and nutritional effects. Its biological and physico-chemical properties make it an attractive biopolymer for applications in many
areas such as food and agriculture, medicine, cosmetics, textiles and water treatment. Shrimp and crab shell wastes from the
sea food industry are widely used for isolation of chitin. The preparation of chitin from shrimp shells, which is composed of
proteins (~49%), calcium carbonate and other minerals (~36%), lipids (4%) and chitin (~11%), involves dissolution of calcium
carbonate and removal of proteins. Deproteination is generally carried out by extraction of protein with >3.0% NaOH at near
boiling conditions for 1-6 h. The objective of this study was to find ways to deproteinate shrimp shells under milder conditions
using sonication. Deminaralized Chitane, a residue of commercial shrimp shells, was deproteinated with an aqueous solution
of NaOH (2%) and NaCl (2%) as solvent by contacting 2.5 g of the residue in 100mL of the solvent. Dispersions were sonicated
with intensity ranging from 50 to 150 W for durations of 5-50 min, at temperature of 40-70 °C. After sonication, the extraction
was continued at the same temperature for a total extraction time of 60 min, including sonication treatment. Protein extractability was monitored by determining nitrogen content with LECO nitrogen analyzer. A nitrogen content of 6.9% ( chitin nitrogen)
in the deproteinated residue was considered to be completely deproteinated. Extractability of protein increased with sonication
energy input as well as temperature. The extractability of protein attributable to sonication alone was independent of temperature. Results suggest that it may be possible to deproteinate shrimps shells at lower extraction temperatures and times.
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P-42
Study of sea bass salting process with sodium replacement
Fuentes A., Barat J.M.*, Serra J. A., Fernández-Segovia I.
IU-IAD Departamento de Tecnología de Alimentos, Universidad Politénica de Valencia, Valencia, Spain
T
he reduction of the sodium content in food products is desirable because of the excessive amount of sodium intake in the
diet, which is associated to health disorders like hypertension. One of the possible strategies is the NaCl replacement with
potassium salts. Salted fish products are susceptible to the above mentioned Na reduction, but the influence of the Na replacement on the salting process and product characteristics is not well known.
The aim of this study was to analyze the sea bass salting process by using different mixtures and amounts of NaCl and KCl,
with special attention to its influence on the water activity of the salted product.
Four salt mixtures were used (100% NaCl, 75% NaCl-25% KCl, 50% NaCl-50% KCl, 25% NaCl-75% KCl) in the study. Sea
bass fillets were salted at 4 ºC for 72 h by covering their flesh with an exact amount of salt to reach a previously defined solute
concentration on dry basis ( ), which were 0.110, 0.150, 0.200, 0.220 and 0.270 (g solute/g dry material). Analyses of moisture,
Aw, as well as chloride, sodium and potassium concentrations, were carried out in all salted samples.
Experimental water activity was compared with theoretical aw obtained by considering the salted fish as a non-ideal aqueous
solution of electrolytes and using the Pitzer and Bromley (1987) prediction equation. This equation is based on the assumption
that there are little interactions among solutes and therefore, their contributions to the chemical potential are additive.
Results showed some differences in the salting process depending on the used mixture. It was observed that 100% NaCl reduced samples weight and water content in greater extent than the rest of mixtures, while a lower increase in the solute uptake
was obtained. Final solute concentrations in sample swere closer to the theoretical ones for the lowest concentrations and the
highest Na replacement. The relationships between the experimental and the theoretical solute concentrations (dry basis) were
obtained for each mixtureof salt, R2 ranging from 0.981 to 0.998. In addition, the experimental aw was related with the solute
concentration in the fish.
The combination of both equations (linear regression and relationship of Aw), allows to know the exact amount of salt to be
added during the sea bass salting process, to reach the desired aw value. This procedure would be interesting in order to obtain
more homogeneous products from the sensory and safety point of view.
152
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51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
Seafood, marine ingredients
and health
Poster session
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
153
Seafood, marine ingredients and health
P-38
Identification and characterization of antibacterial peptides
in enzymatic hydrolysates obtained from fish and
marine by-products of the Eastern Quebec area
Beaulieu L.1,2*, Thibodeau J.1,2, Desbiens M.2, Thibault S.2, Bryl P.2
1. Université du Québec à Rimouski (UQAR)
2. Centre technologique des produits aquatiques - MAPAQ, 96, montée de Sandy Beach, bureau 1.07, Gaspé (QC) Canada G4X 2V6
T
he marine environment is an abundant source of bio-diversity but only very little of this rich resource has been studied.
Most marine organisms, living in a microbe-rich oceanic environment, rely heavily on the antimicrobial components of their
innate immune defences to combat pathogens. Several types of antimicrobial peptides have been isolated from mollusca,
crustaceans, amphibians, fish and mammals.
Following the enzymatic hydrolysis of the marine biomasses; snow crab by-products (Chionocetes opilio), entire mackerels
(Scomber scombrus) and herrings (Clupea harengus), extraction was performed in order to separate the oil and aqueous
phases. Fractionation of proteins/peptides was achieved using micro-filtration, ultra-filtration and reversed osmosis membrane
systems. The resulting protein hydrolysates were subsequently analyzed. About twenty reference bacterial strains were tested
for inhibitory activity. Several peptide fractions originating from snow crab demonstrated inhibitory activity which appeared to
be due to the presence of a proteinaceous compound. In addition, the optimal inhibitory activity was observed at alkaline pH.
Finally, the most bacterial sensitive strain was used to pursue the development of more specific purification methods. The most
promising media were selected for the purification of peptides of interest and to carry out their detailed biochemical characterization (molecular weight, isoelectric point, amino acid composition/sequence). Similar studies are performed for the detection
of antibacterial peptides in enzymatic hydrolysates obtained from mackerel and herring.
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Seafood, marine ingredients and health
P-7
Isolation and characterization of fucoidan from Ascophyllum nodosum
(Phaeophyceae, Fucale) harvested along Canadian and French coasts
Garon-Lardière S.1, Rioux L.-È.1*, Colliec-Jouault S.2, Ratiskol J.2, Sinquin C.2, Turgeon S. L.1
1. Institut des nutraceutiques et des aliments fonctionnels Université Laval, Pavillon Paul-Comtois Sainte-Foy (QC) Canada G1K 7P4
2. Laboratoire de biotechnologie et molécules marines, Ifremer, BP 21105, 44311 Nantes Cedex 3, France
M
arine brown algae are an abundant source of fucoidan, a sulfated polysaccharide that has been known to exhibit various
biological actions, such as an anti-inflammatory or antioxidant action. However, the specific structural motifs that confer
biological activity remain to be more precisely defined. We have now isolated, purified and compared two sulfated fucoidans
extracted from the marine brown algae Ascophyllum nodosum (Phaeophyceae, Fucale) coming from 2 different continents. The
analysis of both extracts was performed using gas chromatography, infrared spectroscopy, electrophoretic analysis and high
performance size exclusion chromatography coupled with multi angle laser light scattering (HPSEC-MALLS). Both extracts
were rich in sulphated fucose and were fucoidans, but the canadian fucoidan presented a higher amount in fucose units than
the french fucoidan with a same content of sulphate groups. Both fractions of fucoidan, in addition to fucose and sulphate,
contained also other neutral monosaccharides, as well as uronic acids. However, fucoidans from the french fraction were enriched with L-rhamnose, while those from canadian coast were enriched with glucuronic acid. Structural details of the fucoidan
moieties of canadian Ascophyllum nodosum, mainly composed of homofucans or fucans, show it similarity with the fucoidan
from France. The molecular weight average (Mw) of the canadian extract was significantly lower than the french extract. The
analysis revealed a Mw of 55 820 g•mol-1 and 106 000 g•mol-1 for the canadian and french extract respectively. All analysis
performed indicate important structural differences between both extracts.
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
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P-18
Optimization of the hydrolysis process of blue whiting
(Micromesistius poutassou) co-products, for the generation of
gastrin/cholecystokinin and CGRP related peptides
Cudennec B.1,2*, Ravallec-Plé R.3, Aubertin S.2, Latinier M.2, Fouchereau-Peron M.1
1. UMR 5178 CNRS/MNHN/UPMC BOME, Marine Biology Station, Concarneau cedex, France 29182
2. Compagnie Des Pêches Saint-Malo Santé, Saint Malo, France 35400
3. ProBioGEM IUT A Polytech’Lille, (Aile C), Villeneuve d’Ascq cedex, France 59655
F
ish protein hydrolysates (FPH) are of interest due to their potential application as a source of bioactive peptides in the
nutraceutics domain. To explore the possibility of obtaining biologically active molecules from hydrolysates of marine processing wastes, we looked for the presence of immunore activities and biological activities related to peptide hormones in fish
hydrolysates. A principal aim of our work is to industrially produce marine ingredients that are beneficial for human health,
and can, in a preventive manner, provide workable solutions to major public health issues such as migraine and obesity. Our
study was focused on two hormonal groups of high use in therapeutics: the calcitonin gene related peptide (CGRP) and the
gastrin/cholecystokinin (CCK). Blue whiting co-product hydrolysates were prepared by the Compagnie des Pêche Saint-Malo
Santé using the pH-stat method. The hydrolysis degree (DH) was calculated, and hydrolysates were analysed for the presence of gastrin/CCK related peptides using a specific radioimmuoassay. The CGRP related molecules were quantified by
a radioreceptor assay developed using rat liver membranes, a specific target organ for CGRP in mammals. Three enzymes
among the eight investigated were selected for their capacity to generate molecules related to gastrin/CCK and/or CGRP.
Bioactive peptides accounted for 425 and 4 pg•mg-1 of dry weight for CGRP and CCK related peptides, respectively. In a
second step, the best hydrolysis conditions for each of the selected enzymes were determined by quantifying bioactive peptides under various conditions of temperature, pH and enzyme substrate ratio. In parallel, the molecular weight repartition of
peptides in each hydrolysate was determined by size exclusion chromatography (SEC-FPLC) coupled with GPC software. The
resulting data showed no relationship between DH and peptide quantity obtained. Similarly, the molecular weight distribution
under each experimental condition was not related to the quantity of bioactive peptides. Nonetheless, all these data suggest
which hydrolysis conditions are the best for obtaining the peptides of interest. Further studies are in progress to determine the
molecular weight of the peptides involved in biological activities. A specific in vivo test for gastrin/CCK-like molecules is under
development to study the mode of action and biological effects of the FPH purified fractions using pre-obese rats. To determine
the receptor subtype involved in the CCK-like stimulation response, a test in vitro is in progress using AR4-2J cell line. A second
in-vitro test, specific for CGRP related molecules, will assess the FPH effect on adenylate cyclase stimulation of CGRP-related
molecules in rat liver membranes.
Supported by a grant from the European community: FEDER-INTEREG IIIB-VALBIOMAR.
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Seafood, marine ingredients and health
P-20
Presence of CGRP related molecules in fish protein hydrolysates from
industrial origin
Martinez-Alvarez O.1*, Ravallec-Plé R.2, Delannoy C.3, Vercaigne-Marko D.2,
Guillochon D.2, Fouchereau-Peron M.1
1. UMR 5178 CNRS/MNHN/UPMC, Station de Biologie Marine, Concarneau cedex, France 29182
2. ProBio GEM-IUT A-Polytech’Lille, (Aile C), Villeneuve d’Ascq, cedex, France 59655
3. Compagnie de Traitement des Produits de la Pêche (CTPP), Boulogne sur Mer, France 62200
I
n order to explore the possibility to obtain biologically active peptides from hydrolysates of marine processing wastes, we
searched for the presence of immunore activities and biological activities related to peptide hormones in fish hydrolysates
of industrial origin. This study was focused on the calcitonin gene related peptide (CGRP), a peptide hormone belonging to
the calcitonin/ CGRP family. These peptides are derived from the calcitonin gene by an alternative splicing mechanism. CT is
mainly use in hypercalcemia associated with or without bone involvement (Paget disease, osteoporosis). The wide distribution
of CGRP-containing nerve fibers and its receptors in the body suggests that this neuromediator plays an important role in the
modulation of physiological functions, namely in the cardiovascular system and the central nervous system. Therapeutic potentials of CGRP receptor ligands include the search for specific agonists useful as vasodilatory agents and antagonists helpful in
several diseases including migraine and inflammation. Siki (Centroscymnus coelolepsis) hydrolysates were prepared by CTPP
and their content in CGRP related molecules quantified by a specific radioimmunoassay. In a second step, CGRP radioreceptor
assays were used to demonstrate that the immunoreactive molecules were also biologically active. Exclusion chromatography
of this hydrolysate showed that the CGRP related molecules are in the range of 3500 to 1500 daltons. In order to study the
biological activity of these molecules, adenylate cyclase assay were used and we demonstrated that the FPH hydrolysates
contained CGRP related molecules able to stimulate the adenylate cyclase in rat liver membranes, a target organ for CGRP
in mammals. HPLC chromatography was used to further purify these molecules. Using two HPLC purification steps, we were
able to obtain a purified fraction that interacts in the CGRP radioreceptor assay.
Further work will firstly focus on the MS/MS analysis of the purified peptides and secondly on in vivo test in order to control the
vasodilatory action of the total hydrolysates in mammals.
Supported by a grant from the European community: Seafoodplus-CT-2004-506359.
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P-16
Technical and economical feasibility of omega-3
PUFAs and phospholipids production from
Northern shrimp (Pandalus borealis) eggs
Girault L.1*, Rondeau M.-H.1, Boumghar Y.2, Beaulieu C.3
1. Centre collégial de transfert de technologie des pêches, Grande-Rivière, Canada
2. Centre d’études des procédés chimiques du Québec, Montréal, Canada
3. Marinard Biotech Inc. Gaspé, Canada
T
he northern shrimp (Pandalus borealis) fishery worldwide is presently facing low prices and severe competition fron the asian
shrimpfarms. In this context, bringing added value from the shrimp coproducts has become a crucial matter to the industry.
During the early spring shrimp fishery in eastern Canada, thousands of tons of eggs are discarded at the processing plants.
This readily available biomass contains potentially valuable lipids, especially phospholipids and omega-3 poly-unsaturated fatty
acids (PUFAs). The project’s objectives were to evaluate: i) the biomass of shrimp eggs landed at the Pêcheries Marinard plant
in the spring, ii) the amounts and types of omega-3 PUFAs and phospholipids found in the eggs, and iii) the costs associated
with their isolation and extraction. Sampling of fresh eggs took place every week in April of 2004, at the Rivière-au-Renard
landing dock and from the Marinard plant’s washing tubs. The lipid phase was extracted from the eggs by supercritical CO2.
PUFAs and phospholipid contents of the extracts were determined using standard HPLC techniques.
Fifty metric tons of eggs entered the plant in April, about half of which could be collected and separated at low costs (0,25 $/kg).
Eggs abundance decreased through the month, while their individual size increased, and the shrimps initiated laying by the
15th of April. The eggs proved very resilient to handling, filtering and osmotic shocks. CO2 extraction efficiency was therefore
limited, and only 7 of the 21 samples collected were successfully treated. Analysis of these samples showed a mean 45 mg/g
for EPA + DHA in the extracts (16,5% w/w of the lipid fraction), not enough to sustain a commercial exploitation of the eggs’
PUFAs. However, phospholipids accounted for 60% w/w of the lipids, which is significantly higher than values reported for other
crustacean eggs. Phosphatidylglycerol, a rare polar head group also found in the heart of mammals, represented 54 ± 15% of
the phospholipids, an unusual amount for marine lipids. This finding could be interesting if a significant proportion of this phosphatidylglycerol were linked to omega-3 side chains: a (PG-PUFAs) combination could cause the omega-3 to be adressed specifically to the heart tissues of consumers, thereby enhancing the heart-protective potential effects of the omega-3 PUFAs.
158
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51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
New concepts to minimize
seafood associated risks
Poster session
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
159
New concepts to minimize seafood associated risks
P-40
Biopreservation potential of divergicin M35
to inhibit Listeria monocytogenes in wild cold smoked salmon
Tahiri I.1*, Desbiens M.2, Kheadr E.1, Lacroix C.3, Fliss I.1
1. Groupe STELA Institut des Nutraceutiques et des Aliments Fonctionnels (INAF), Université Laval, Québec (QC) Canada G1K 7P4
2. Centre technologique des produits aquatiques Ministère de l’Agriculture des Pêcheries et de l’Alimentation, Gaspé (QC) Canada G4X 2V6
3. Institute of Food Science and Nutrition, Swiss Federal Institute of Technology, ETH Zentrum LFO F18, Zurich, Switzerland CH-8092
T
he aim of this study was to evaluate the potential of divergicin M35, a new class IIa bacteriocin produced by Carnobacterium divergens M35 isolated from frozen smoked mussels, to inhibit L. monocytogenes growth in wild cold-smokedsalmon (CSS). Samples of CSS were firstly inoculated with C. divergens M35 (106 CFU/g), purified divergicin M35 (50 µg/g)
and divergicin M35 bioingredient obtained from snow crab hepatopancreas fermentation, a natural food-grade media. Thereafter, L. monocytogenes LSD 532 was inoculated at a final concentration of 103 CFU/g. Fillets were packaged and stored
for 28 days at 4°C. The evolution of total count, lactic acid bacteria and L. monocytogenes viable counts, Total Volatile Base
Nitrogen (TVBN), biogenic amines and sensorial characteristics were investigated. A three 3-log reduction in viable count of
L. monocytogenes was obtained after nine days of storage and was attributed to in situ production of divergicin M35 as a result
of C. divergens M35 growth in CSS. No acidification was observed over the 28 days of storage. Color and texture were not affected in samples containing C. divergens M35 compared to un-inoculated samples which showed a discoloration and a pasty
texture after 15 and 21 days of storage, respectively. These results suggest that C. divergens M35 has a powerful biopreservative potential against pathogenic bacteria such as L. monocytogenes in ready-to-eat seafood products. The results relative to
the inhibition of L. monocytogenes in CSS by SCH bioingredient and purified divergicin M35 will be shown.
160
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51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
New concepts to minimize seafood associated risks
P-12
Degradation of Paralytic Shellfish Poisoning (PSP) toxins by different
bacterial strains
Ku J.1,2*, Donovan C.2, Quilliam M.1, Gill T.2
1. Institute for Marine Biosciences, NRC, Halifax (NS) Canada B3H 3Z1
2. Department of Process Engineering and Applied Science, Dalhousie University, Halifax (NS) Canada B3J 2X4
P
aralytic shellfish poisoning (PSP) toxins are potent neurotoxins produced by several marine dinoflagellates. The accumulation of these toxins during « red tide » episodes can have serious economic and public health repercussions. PSP
toxins are tetrahydropurine derivatives based on the parent compound, saxitoxin (STX), and can be divided into three classes:
carbamate, N-sulfocarbamoyl and decarbamoyl toxins. Over 18 structural analogues have been identified. The toxicity of STX
analogues is attributed to the reversible blockage of voltage-activated sodium channels on excitable cells.
Different strains of bacteria cultures isolated from toxic blue mussel were incubated with marine broth, mussel and toxic algal
extract. Samples were taken sequentially over time and changes in toxin levels were monitored by ion-pair liquid chromatography using reversed phase columns coupled with post-column oxidation and fluorescence detection (LC-ox-FLD). LC-MS/MS
was used to identify any new compounds resulted from the toxin breakdown. The significance of this work on the safety aspects
of cultured shellfish will be discussed.
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
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New concepts to minimize seafood associated risks
P-31
Effect of modified atmosphere packaging on melanosis in frozen deepwater rose shrimp (Parapenaeus longirostris)
Bono G.*, Baldrati G., Badalucco C.
1. Istituto per l’ambiente Marino Costiero del CNR (IAMC-CNR), via L. Vaccara 61 91026, Mazara del Vallo, Italy
2. Viale Monte Grappa 12 - 42100, Reggio Emilia, Italy
T
he melanosis of crustaceans is usually limited by the useof sulphites that extend the shelf-life of most fishery products by
inhibiting oxidative reactions. As an alternative, this work examines the effects of modified atmosphere packaging (MAP)
technology on melanosis of frozen deep-water rose shrimp.Thus, shrimp were packed in oxygen barrier bags and flushed with
100% nitrogen and a mixture of nitrogen and CO2 (50%-50%) on board a commercial trawler. Then all samples were stored
in a freezer at -20 °C and microbial analysis, biochemical changes and sensory evaluation were carried out every two months
throughout a storage period of one year. At present, biochemical parameters (pH, TBARS and ABTV) and sensory evaluations
(odour, colour and flavour) show that MAP packaging of shrimp can be recommended to replace food additives in extending
the shelf-life of deep-water shrimp.
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New concepts to minimize seafood associated risks
P-53
Effectiveness of lemon juice in the elimination
of Salmonella typhimurium in stuffed mussels
Kisla D.*
Ege University, Faculty of Fisheries Department of Fishery and Fish Processing Technology, 35100 Bornova, Izmir, Turkey
S
tuffed mussel is a delicious street food sold by vendors in coastal parts of Turkey. It is prepared by stuffing rice, vegetable
oil and seasonings mixture into the shell including the mussel meat and it is cooked by steaming. Familiarity, taste, low-cost
and convenience are some attractive factors that make street foods popular as food source. However, characteristics of the
product and the lack of sanitary practices increase concerns about the potential for food poisoning due to microbial contamination. Foods of animal origin are the most implicated sources of Salmonellosis. In this study, stuffed mussel (edible part) will be
inoculated Salmonella typhimurium suspension to provide approximately 6 log CFU/g. After inoculation, sample will be treated
with two types of lemon juices (fresh squeezed and commercial one) for 0, 5 and 10 min, and pathogens will be enumerated by
using direct plating on Bismuth Sulphite Agar. The objective of this study is to investigate the bactericidal activity of lemon juice
against Salmonella typhimurium added to stuffed mussel.
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
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New concepts to minimize seafood associated risks
P-14
Pulsed light (PL) treatment of vacuum
packaged (VP) cold smoked salmon
Pollock A.M.1*, Ramaswamy H.S.1, Ngadi M.O.2
1. Department of Food Science and Agricultural Chemistry, McGill University, Montréal, QC
2. Department of Bioresource Engineering, McGill University, Montréal, QC
L
isteria monocytogenes is a common post-processing contaminant in ready-to-eat vacuum packaged (VP) cold smoked
salmon. Since this psychrotrophic pathogen can grow at refrigerated temperatures (~4 °C), additional safety barriers other
than temperature are needed to ensure the continued safety of VP cold smoked salmon. One such novel barrier could be the
use of pulsed light (PL) treatment. The objective of this study was to evaluate the effect of various intensities and durations
of PL on (1) the inactivation of L. monocytogenes and (2) the sensory quality (colour, texture and odor) of VP cold smoked
salmon.
Inactivation kinetics of L. monocyotgenes was evaluated at various PL treatments in vitro by surface plating of the bacteria onto
a general purpose nutrient agar medium. The following PL criteria were used to evaluate the destruction kinetics: distance from
the PL source, 5, 10 and 15 cm; intensity, 600, 700 and 800 V with a pulse frequency of 1 pulse per second (pps); and various
treatment times (from 0 to 60 s). Sensory quality was then monitored on uninoculated VP cold smoked salmon subjected to
selected PL treatment and stored for 14 days at 4 °C. Inactivation kinetics parameters (D value and z) were computed based
on a first order rate of destruction. No change in sensory quality was observed.
Subsequently, challenge studies were performed on inoculated vacuum (VP) and air (AP) packaged cold smoked salmon over
a 28 day period at refrigerated (4°C) and moderate temperature abuse (12 °C) conditions.
A small reduction in L. monocytogenes counts was observed when PL treated at 5 cm distance, 800 V for 60 s at 1 pps, with no
observed change in sensory quality in VP samples stored at 4 °C for 14 days. In order to improve the microbial load reduction
in cold smoked salmon by PL treatment, higher voltages (1000-3500 V) or other techniques seem to be necessary.
This study has shown that PL treatment in combination with low temperature storage (4 °C) has the potential to extend the
shelf-life of VP cold smoked salmon products without compromising sensory quality.
164
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
New concepts to minimize seafood associated risks
P-10
Quality changes in yellowfin tuna and mahi-mahi fillets
processed with high hydrostatic presssure
Bolton G. E., Björnsdóttir K., Nielsen D., Petersen A., Green D.P.*
Department of Food Science, Seafood Processing Laboratory, Center for Marine Sciences and Technology, North Carolina State University,
303 College Circle, Morehead City, North Carolina USA, 28557
P
revention of human disease due to seafood-borne intoxications induced by the growth of scombrotoxin-producing bacteria remains a challenge despite recent efforts for its control. The primary measure employed to prevent scombrotoxin
formation in fresh fish has been time and temperature control from point of harvest through distribution and consumption. In
this study, we evaluate the use of high hydrostatic pressure processing (HPP) to eliminate scombrotoxin-producing bacteria
naturally associated with fish, thereby reducing the risks associated with scombrotoxic fish poisoning. Effects of high HPP on
histamine decarboxylase (HDC) activity are discussed. Fresh yellowfin tuna (Thunnus albacares) and mahi-mahi (Coryphaena
hippurus) were purchased from North Carolina licensed seafood dealers in 2004-06. Fish were rapidly chilled in ice, processed
into 100g skinless portions and sealed in barrier film bags before high HPP treatments. Samples were subjected to 200, 300
and 400 MPa for two and five minutes after 0, 5 and 12 days of refrigerated storage at 2.2 oC. Treated and control samples were
plated on tryptic soy agar (TSA) supplemented with 2% sodium chloride to enumerate bacterial colonies. Colonies surviving
400 MPa treatments were isolated and identified using the Becton Dickinson BBL Crystal identification test and the API 20E
Enterobacteriaceae test by bioMerieux Vitek. Effects of high HPP on sample color were determined instrumentally with a Minolta CR-410 colorimeter before and after high HPP treatments. Sensory evaluations were performed by a semi-trained panel
on uncooked (raw) and cooked samples.
Seventy-six isolates were recovered after high HPP at 400 MPa and 55 have been identified. Five isolates tested positive for
histamine production on Niven’s media. Treatments were shown to increase L* values and decrease a* values in uncooked
samples with increased processing pressure. Sensory analysis revealed a decrease in quality of uncooked samples with pressure up to 300 MPa, irrespective of application time. Increasing pressure from 300 MPa to 400 MPa did not alter the quality any
further. Pressure treatment did not affect sensory scores of the cooked samples. All cooked samples deteriorated in appearance, odor, flavor and texture as refrigerated storage time increased irrespective of pressure level or application time. Effects
of high HPP on HDC activity is currently being studied to determine its significance in further reducing risks. Our study showed
that high HPP treatment may reduce but does not eliminate the presence of scombrotoxin-forming bacteria in fresh fish. The
effects of high HPP treatment on HDC activity are currently unknown.
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
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New concepts to minimize seafood associated risks
P-3
Chain: Developing a Stakeholders’ Guide
on the vulnerability of food and feed chains
to dangerous agents and substances
Martinez, 1,7*, Ward, S.1, Butler, F.1, O’Donnell, C.1, Schwaegele, F.2,
LucasLuijckx, N. B.3, Engel, E.4, Berge, P.4, Pospiech, E.5, Mcdonnell, K.6,
Garforth, D.8, Marshall, P.8, Beraquet, N.9, Frewer, L.10
1. University College, Dublin, Ireland
2. Bundesforschungsanstalt für Ernährung und Lebensmittel Meat, Germany
3.TNO Quality of Life, Netherlands
4. Institut National de la Recherche Agronomique - INRA France
5. Agricultural University of Poznan, Poland
6. AgriTech Solutions, Ireland
7. SINTEF, Norway
8. IFQC, Ireland
9. Tecnologia de Alimentos - ITAL, Brazil
10. Wageningen University, Netherlands
T
he European citizen requires harmonised food and feed chain traceability systems that offer protection from poisoning by
dangerous agents and substances. The objective of this project is to develop methodologies that will optimise the traceability process with respect to chain vulnerability to contamination.
This project will evaluate current chain traceability systems, including methodologies for the identification of contaminants.
Chain vulnerability varies depending on chain type, and case studies will be conducted on four «high vulnerability» products,
representing 3 major categories of chains. The products are: drinking water (i.e. a rapid contamination chain); milk powder
(i.e. a batch mixing chain); and both poultry meat and farmed salmon (i.e. long geographic chains). Each of these chains
will be mapped and their vulnerability to contamination assessed. A risk model will be developed to provide quantitative risk
assessments of chain vulnerability. A generic framework will be constructed for the assessment of chain vulnerability and the
prioritisation of chain contamination risk. This framework will be validated using the case studies and wider inputs from stakeholders. The outputs from these tasks will be synthesised into a Stakeholders’ Guide to food and feed chain vulnerability to
contamination. The Guide will be in book format, supported by software that enables the stakeholder to input specific chain data
for a product and produce associated chain maps and assessments of contamination risks. It will also enable the stakeholder
to examine risk minimisation options (viz. corrective measures), such as enhanced security of the most vulnerable links.
This is a 3-year STREP project financed by EU with a budget of approximately €2.9 million with 11 partners (the 11th is SYNCOM Forschungs-und Entwicklungsberatung GmbH, Germany) that achieves critical mass comprising centres of expertise
from universities, research institutes and industry (3 SMEs) spread across the EU (including New EU State Poland) and
3rd country (Brazil). SMEs account for ca. 16% of the budget, and there are venture capital and training programmes in place to
assist them in the exploitation of the outputs. The project started in April 2006 and it has a comprehensive Project Management,
Gender Mainstreaming and Technology Implementation Plan.
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P-37
The traceability systems implementation
in the Polish fish industry
Szulecka O., Bykowski P.J.*
Sea Fisheries Institute in Gdynia, UI. Kollataja 1 81-332, Gdynia, Poland
Introduction
T
he implementation of traceability systems is required since the 1.01 2005 by the Regulation (EC) No 178/2002 of the European Parliament and of the Council of 28 January 2002 laying down the general principles and requirements of food law,
establishing the European Food Safety Authority and laying down procedures in matters of food safety.
Aim and scope of the survey
The main aim of the survey is the evaluation of traceability systems implementation in the Polish fish industry. The prepared
questionnaire with 19 questions was sent by e-mail or fax to the Polish processing plants. 24 processing plants (small-6,
medium-15 and big-3) fulfilled the questionnaires and sent them back to Sea Fisheries lnstitute in Gdynia.
Results
In the presented survey 24 processing plants were questioned about traceability systems implementation. 100% of the surveyed processing plants confirmed the implementation of above mentioned systems. The main difficulties ascertained by more
than 10% of the surveyed operators are connected with inaccurate identification of raw material batches what makes the traceability procedures more difficult. Due to expensive implementation of advanced traceability systems more than 50% of the
surveyed processing plants record their data only in paper documents and less than 50% are interested in advanced traceability systems implementation. The results of the survey obtained from the fish processors show that one third of the surveyed
processing plants do not verify their traceability systems what can cause the problems with the fast and efficient risk analysis
and product recall procedures. What seems to be also important the new traceability of food packaging materials requirement
is still not implemented in one fourth of the surveyed processing plants.
Conclusions
The Polish fish industry was properly prepared for the HACCP system implementation what undoubtedly helped in traceability
systems implementation. The surveyed fish operator opinions about traceability systems have changed during last two years
and nowadays all of the surveyed fish operators understand the legislation requirements and idea of traceability systems.
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convenient seafood and ingredients
Poster session
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P-26
Comparative properties of carboxy-, oxy- and
met-hemoglobin from tilapia
Kristinsson H.G.*, Mony S.S.
Laboratory of Aquatic Food Biomolecular Research, Aquatic Food Products Program, Department of Food Science and Human Nutrition, University of Florida Gainesville, Florida USA, 32608
O
xygen transport proteins such as myoglobin and hemoglobin play an important role in quality deterioration of fish fillets by
promoting lipid oxidation and leading to color changes. Hemoglobin’s pro-oxidative property increases when it auto-oxidizes into met-hemoglobin. Furthermore, met-hemoglobin gives the fish muscle an unappealing brown color. To delay formation
of the met-form, it is important to increase the stability of hemoglobin. This can be done by the binding of specific ligands to the
heme porphyrin group, such as carbon monoxide (CO), which is common practice nowadays. Little is known how this form of
hemoglobin in fish compared to the other common forms, oxy- and met-hemoglobin
The objective was to perform a comparative study on the conformation, structural and oxidative stability of CO-, oxy and methemoglobin. Our hypothesis was that binding CO to hemoglobin would increase its resistance to auto-oxidation, thermal, pH
and chemical denaturation.
Oxy-hemoglobin was isolated from fresh tilapia blood. CO-hemoglobin was prepared by flushing a hemoglobin solution with
100% CO for 2 min. Met-hemoglobin was prepared by reacting oxy- hemoglobin to sodium ferricyanide. Auto-oxidation was
induced by storing the different hemoglobin derivatives different pH and temperature for several days. Changes in their UV-Vis
absorption spectra were monitored and used to calculate percent auto-oxidation. The three derivatives were also subjected to a
series of thermal denaturation experiments at different temperatures. Extent of denaturation was determined by their change in
heme peak environment and protein aggregation, by UV-Vis spectral analysis, and changes in secondary and tertiary structure
with a circular dichroism spectrometer. Thermal stability was also studies using a micro-differential scanning calorimeter. pH
denaturation studies were performed at low pH and changes in visible spectra, tryptophan florescence and secondary structure were monitored. The three hemoglobins were also subjected to guanidine hydrochloride (Gu-HCl) and urea denaturation
studies, following changes in heme group environment and tryptophan fluorescence. Pro-oxidative activity of the three forms
was evaluated in a linoleic acid emulsion and a washed tilapia muscle system.
Results clearly demonstrated that CO-hemoglobin greatly resisted oxidation, significantly more so than oxy-hemogobin. Increased pH, from 6 to 8, increased oxidative stability of both forms, while increased temperature destabilized both forms. From
all conformational assays it was evident that CO-hemoglobin had the highest thermal stability, followed by oxy-hemoglobin,
with met-hemoglobin demonstrating the least stability. Chemical denaturation with Gu-HCl supported the thermal denaturation
results, while urea denaturation did not reveal a difference in the stability of CO and oxy-hemoglobin. CO-hemoglobin was also
found to be less pro-oxidative than the other forms. Both UV-Vis spectra and circular dichroisms spectra clearly demonstrated
that there are structural differences between the three different forms, which very likely influence their stability. The results
suggest that the heme group environment, where the gas ligands bind, are different for the different forms, thus influencing
stability and pro-oxidative activity.
These results show that carbon monoxide binding greatly stabilizes the heme group and thereby the whole protein molecule.
This is likely one reason why seafood’s treated with CO containing gases have improved shelf-life.
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P-5
Composition and rheological characterization of polysaccharides
extracted from brown seaweeds from Eastern Canada
Rioux L.-È.1*, Turgeon S. L.1, Beaulieu M.2
1. Institut des nutraceutiques et des aliments fonctionnels, Faculté des sciences de l’agriculture et de l’alimentation, Université Laval, Québec
(QC) Canada G1K 7P4
2. Nestlé Research Center, 1000 Lausanne 26, Lausanne, Switzerland
H
ydrocolloids from seaweeds have interesting functional properties like thickening or gelling ability while others are mostly
studied for their biological activities. Structural characteristics of polysaccharides extracted from Quebec seaweeds have
not yet been established. Thus, the determination of the relationship between structure and their rheological behaviour is limited. Alginate and fucoidan were extracted using selective solvents from three species; Laminaria longicruris, Ascophyllum nodosum and Fucus vesiculosus. Structural analysis (total sugars, uronic acids, sulphates and molecular weight) and rheological
characterization were performed at different polysaccharide concentrations with and without the addition of NaCl. The results
showed important structural variation between species. Fucoidan’s molecular weight was of 127.3, 90.3, 39.6 kDa respectively
for A. nodosum, F. vesiculosus and L. longicruris while for alginate the molecular weight was of 164.7, 134.9 and 122.4 kDa.
Fucoidan and alginate exhibited Newtonian behaviour. Fucoidan extracted from F. vesiculosus had the highest viscosity level,
which might be explained by the degree of branching of the molecules since its molecular weight is smaller than A. nodosum.
For alginate, the one extracted from L. longicruris showed a higher apparent viscosity. This result can partially be explained by
the block proportion of this alginate and by the amount calcium naturally found in alginate samples. The gelation profile of alginate was also determined for each species. The final storage modulus G’ was variable for each species. Differences between
species were observed for both polysaccharides as a result of structural variation. There are currently no published accounts
of fucoidan for assessing composition and structure with rheological behaviour. Although for alginate, G’ was found to be lower
than other extract from different studies. Moreover, its viscosity was found to be similar to other research while the solutions
exhibit a shear-thinning behaviour.
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P-35
Could fish replace mammals for the supply of
industrial proteases? A comparison of the
functional properties of wolffish and bovine trypsin
Desrosiers V.1, Blier P.U.1*, Le François N.1,2
1. Laboratoire de biologie intégrative, Université du Québec à Rimouski, 300, Allée des Ursulines, Rimouski (QC) Canada G5L 3A1
2. Centre aquacole marin de Grande-Rivière, Ministère de l’Agriculture, des Pêcheries et de l’Alimentation du Québec, 6, rue du Parc GrandeRivière (QC) Canada G0C 1V0
T
rypsin was recovered from Atlantic wolffish (Anarhichas lupus) and their properties compare with those of commercially
available bovine trypsin. Trypsin purification was realized by a combination of 40-60% saturation sulphate ammonium fractionation, acetone precipitation, ultrafiltration on 100 kDa NMW and 50 kDa NMW membrane. Purification was about 40-fold
with a recovery of 17%. Trypsins were studied by amidase activity assays using BAPNA as substrate. Aprotinin and soybean
trypsin inhibitor, two basic trypsin inhibitors, had inhibitory effects on enzymes. Aprotinin effect suggests serine properties. Both
trypsins had similar wide range of pH optimum (pH 7-10) and similar activity profiles with increasing Tº. Wolffish trypsin had an
optimal activity at pH 9 and as bovine trypsin, exhibited increasing activity at temperatures as high as 75 ºC. The pH stability
profiles at 25 ºC and 45 ºC were similar for both trypsins, but wolffish trypsin was more stable in alkaline conditions at low
temperature (5 ºC). Thermostability in the range of 5 ºC to 75 ºC was clearly higher for wolffish trypsin, as well as the stability in
long exposition (96 hrs) at 25 ºC. In conclusion, wolffish differ mainly from bovine trypsin by its temperature sensitivity characteristics and alkaline stability at low temperature. Atlantic wolffish appeared to be an interesting source of digestive proteases
with unique properties, which could find their own technological applications.
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P-22
Electromigration of chitosan D-glucosamine
and oligomersin dilute aqueous solutions
Aider M.1*, Arul J.1, Mateescu A.-M.2, Brunet S.3, Bazinet L.1
1. Institute of Nutraceuticals and Functional Foods (INAF), Department of Food Sciences and Nutrition, Laval University, Québec (QC) Canada
G1K 7P4
2. Department of Chemistry and Biochemistry, Université du Québec à Montréal, C.P. 8888, Succursale A, Montréal (QC) Canada H3C 3P8
3. ISM Biopolymer inc., 220, Denison E., Granby (QC) Canada J2H 2R6
E
lectromigration behavior of chitosan D-glucosamine and oligomers with degree of polymerization from 1 to 6 in dilute
aqueous systems containing either NaCl and KCl salts at 0.01, 0.05 and 0.1 M at pH values from 2 to 9 was evaluated.
The results showed that the electromigration of the chitosan D-glucosamine and oligomers did not change by changing the
type of salt in the running medium and that the pH had a significant effect on the direction of migration under external electric
field. In addition, the increase in the ionic strength of the medium caused a significant decrease on the absolute value of the
electrophoretic mobility and the highest values of the electromobility were observed in water. However, the ionic strength had
no significant effect on the electrophoretic mobilities at pH 2 in comparison with the other pH values. The dimer showed the
highest electrophoretic mobility in the alkaline zone of the pH. At pH values lower than the pKa of the D-glucosamine, the
chitosan D-glucosamine and oligomers migrated towards the anode where the amine groups are protonated and carry positive
charge. At higher pH values, chitosan D-glucosamine and oligomers migrated towards the anode even though they did not
carry any electric charge. The contribution ofthe difference in the dielectric constants between the solvent and the solute to this
phenomenon was highlighted. It was shown that the glucose moiety contributes to the direction of migration of the chitosan
D-glucosamine and oligomers under alkaline conditions and that the difference in the dielectric constant of glucose and the
solvent accounts for the direction and the extent of electromobility.
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P-41
Physical stabilization of omega-3 fatty acids in surimi gel
Tolasa S.1*, Lee C.M.2, S. Cakli1
1. Ege University Fisheries, Faculty, Dept. of Fish Processing Technology Izmir, Turkey
2. Dept. of Nutrition and Food Sciences, University of Rhode Island, Kýngston, Rhode Island USA
S
urimi is a washed, cryostabilized fish mince and used as a highly functional myofibrillar protein ingredient. In view of the important role of omega-3 fatty acids in health, its addition to surimi could yield a nutritional seafood that mimics high omega-3
fatty acids-containing natural fish products. Emulsion or physical entrapment has been employed to stabilize oils in processed
food systems. It is believed that finely dispersed oil droplets are protected by either protein membranes or a cohesive protein
matrix. The principle of physical entrapment can be applied in stabilizing fish oil in surimi gel. In order for the surimi gel to have
a good protective function, the gel should have a highly cohesive matrix which allows uniform dispersion of fine oil droplets.
The objective of this study was to compare the dispersion and oxidative stability of omega-3 fatty acid oil in high and low quality
surimi gels during refrigeration storage when surimi gels were fortified with algal DHA or concentrated fish oil EPA-DHA at 0.5%
and 1% levels.
Gels of both low and high quality were prepared with Alaskan pollock surimi of SA grade, 4% freeze-thaw stable starch, 2%
salt and 0.5% or 1% oil using a Stephan vacuum chopper. The resulting surimi gels were vacuum packed and pasteurized at
85°C for 15 min. Surimi was subjected to 7 freeze-thaw cycles to produce a low quality surimi gel with compressive force 5.6 kg
penetration force 81.6 g and strain at failure 0.57, compare the 62.6 kg, 3.8 g and 0.84 for high quality surimi gel. The effect
of surimi gel properties on oil dispersion was examined using light microscopy. The extent of lipid oxidation was monitored by
thiobarbituric acid reactive substances (TBARS) and hydroperoxides value during 2 month storage.
Very fine and uniform oil dispersion was observed with the average droplet size of 6.25 µm in the high quality surimi gel compared to 26.78 µm in the low quality gel. Both hydroperoxide and TBARS values were lower, 3.75 meq/kg and 0.41 µmol/100g, in
the high quality surimi gel, while significiantly higher values, 5.2 meq/kg and 3.35 µmol/100g, were observed in the low quality
surimi gel.
Results confirm that a highly cohesive gel matrix is required to have a fine dispersion and oxidative stability of omega-3 fatty
acid oil in the surimi gel system.
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P-24
Sensory profiling of three fish species caught
in the Southern Adriatic Sea
Badiani A.1, Testi S.1*, Bonaldo A.1, Foschi C.2, Fagioli C.1, Gatta P.P.1
1. DIMORFIPA Alma Mater Studiorum University of Bologna, Bologna, Italy
2. Laboratorio di Acquacoltura Alma Mater Studiorum, University of Bologna, Cesenatica (FC), Italy
Objective
To develop and compare the sensory profiles obtained in two seasons for European hake (Merluccius merluccius), chub mackerel (Scomber japonicus), and horse mackerel (Trachurus trachurus) caught off the Apulia coast (Southern Italy).
Methodology
Two batches per species (25 fish each) were obtained in July and October 2005 for European hake (EHK) and chub mackerel
(CMK), in July 2005 and March 2006 for horse mackerel (HMK). Fish were eviscerated, frozen, and stored at -20 °C ± 2 °C
over 3 to 5 weeks prior to sensory analysis. This was performed on skinned fillets individually cooked at 71 °C core temperature
in a preheated (120°C) forced air convection oven, in such a way so as to prevent each fillet from both drying and simmering in
its own fluids. The trained descriptive analysis panel (n = 10) evaluated samples on a 10-cm unstructured line scale anchored at
both ends. Panellists used a previously developed ballot containing the following attributes: whiteness, visual flakiness, overall
odour intensity, overall flavour intensity, sour, salty, stringiness, moistness, adhesiveness, tenderness, chewiness, meltability.
Summary of the main results
As to the appearance, EHK were judged to be whiter and less visually flaky than CMK and HMK, independently of catch
season. EHK were also characterised by the lowest intensity of both odour and flavour. At the other end of the spectrum lay fall
CMK, while winter HMK were in-between. As to the basic tastes, summer CMK flesh was perceived as the sourest, EHK as the
least acidic. CMK, both catch season, and winter HMK were significantly saltier than EHK, especially the fall samples. It was in
the textural attributes, though, that differences among species became wider. EHK, both catch season, were at the lower end
of the spectrum as to stringiness and adhesiveness, at the upper end as to moistness, tenderness, chewiness, and meltability.
CMK, both catch season, and summer HMK were « sensorily antithetical » to EHK, whereas, as already observed for odour
and flavour, winter HMK displayed intermediate textural properties.
Acknowledgements
The full cooperation of the « Consorzio per il Mercato Ittico all’Ingrosso di Manfredonia » (Manfredonia, Italy) is gratefully
acknowledged.
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P-33
Trypsin activity measurement in fish and mammals:
comparison of four different methods
Lemieux H., Blier P.U.*
Laboratoire de biologie intégrative, Université du Québec à Rimouski, 300, Allée des Ursulines, Rimouski (QC) Canada G5L 3A1
T
rypsin is known as a quantitatively important proteolytic enzyme in animal digestive systems. Because of its many industrial
and research applications, trypsin has been thoroughly characterized in a wide variety of organisms. Its activity is usually
measured using synthetic substrates, principally amide and ester derivatives of the amino acids lysine or arginine, which possess only one bond that can be easily broken. The aim of this study was to compare trypsin activity measurement obtained
with different methods. We include four widely used methods: two using amide substrates (benzoyl-L-arginine-p-nitroanilide
and N-α-benzoyl-L-arginin-methyl-coumarinylamide) and two using ester substrates (N-p-toluenesulfonyl-L-arginine methyl
ester and N-α-benzoyl-L-arginin ethyl ester) to measure activity in pure commercial enzyme extracts (bovine and Atlantic cod,
Gadus morhua) as well as in animal tissues (mice and Atlantic cod) at four different temperatures (5, 15, 25 and 35 ºC). Our
analysis gives information about substrate sensitivity, measurement reproducibility, and differences among taxonomic groups
for the four methods studied.
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Consumers, market and
sea products
Poster session
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P-29
Plasmidic standards to validate fish species identification
methodologies based on the DNA technology
Pardo M.A.*
Food Research Division, AZTI, Instituto Tecnológico Pesquero y Alimentario Txatxarramendi ugartea z/g E-48395 Sukarrieta, Bizkaia,
Portugal
Objective
During the last years several fish species identification methodologies based on DNA technology were developed to fulfil the
European Union regulations (ECNo 104/2000) which indicate the necessity of labelling the seafood products with the scientific
name to assure the traceability system through the whole chain. Most of these methodologies are based on the amplification
by PCR of a specific DNA fragment from the whole genome. To date, the validation of the DNA methodologies have been
performed using a DNA template previously extracted from some well characterised fish samples but this type of techniques
introduces a variation parameter during the DNA extraction step.To solve this handicap, plasmidic standards have been developed. These standards have the same characteristics and composition which ensure the standardization of measurements
and procedures, and thus allowing the comparison of results obtained in different laboratories. Moreover, a precisely quantified
PCR standard provides valuable information about true positive/negative results, the optimum PCR parameter and the estimation of the initial amount of DNA template
Methodologies
Amplification of the complete mitochondrial cytochrome b gene from different fish species were developed in a Mastercycler
Personal from Eppendorf. The amplicons were purified with the GFX-PCR-DNA and Gel Band Purification Kit (Amersham
Biosciences AB, Buckinghamshire, UK). DNA sequencing was carried out directly on the purified fragments with a 3700 DNA
Analyzer ABI PRISM, using the ABI Prism BigDye Terminator Cycle Sequencing Ready Reaction Kit, version 3.0 (Applied Biosystems, Foster City, USA). The complete mitochondrial cytochrome b gene of 1200 bp was cloned into pMOSBlue following
the specifications of the pMOSBlue vector cloning kit (Amersham Biosciences).The insert size was resolved by electrophoresis
and the sequence of the insert was obtained by sequencing using the T7 and U19 primers.
Results
An innovative set of primers were designed in order to amplify successfully the complete mitochondrial cytochrome b gene from
different fish species of gadoids, tunas, hakes and anchovies. The complete gene of fish species was also effectively cloned
into pMOSBlue vector.
A set of cell bank was established and maintained at -80 ºC. A plasmid propagation protocol at the desired scale was optimized
in order to obtain enough quantity for each plasmid. Thus, every plasmid can be shipped in the desired solution and at the
required concentration together with the corresponding quality certifications. The specifications of the quality certificate include:
the purity (spectrophometry at 260 nm), the absence of RNA and genomic DNA, the plasmid identity by sequencing and the
plasmid homogeneity by densitometry in agarose gels.
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Aquaculture and
fish supply
Poster session
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P-58
Effect of refrigerated storage
on the quality of live mussels
Pedro S.*, Castro S., Nunes M.L.
DITVPP-INIAP/IPIMAR, Av. Brasília, Lisboa, Portugal 1449-006
S
hellfish is a food commodity very appreciated worldwide. However, in some regions, live bivalves are often harvested and
stored at room temperatures until dispatch to retailers. Such practice may allow the multiplication of natural spoilage flora
as well as microbial pathogens, posing a potential health threat to susceptible consumers and/or compromising the edible
quality of the product. In order to contribute to the improvement of live bivalve holding conditions the effect of refrigerated storage on the microbiological and physical-chemical quality of live mussels was evaluated. Mytilus edulis was purchased from a
local producer and stored at 3 ± 1 °C and 20 ± 1 °C over a ten day period. Mortality, sensory analysis, total volatile basic nitrogen (TVBN), trimethylamine (TMA), pH, total viable counts (TVC), lactic acid bacteria, H2S producers (H2S+), Pseudomonas,
Enterobacteriacea and E. coli were periodically assessed. Under refrigeration conditions, mortality rate was kept below 10%
until the seventh day of storage. The pH of the bivalves remained around 6.5 over time and no lactic acid bacteria were detected. The TVC, H2S+, Pseudomonas and Enterobacteriacea increased while olfactory acceptance decreased over time. TVBN
and TMA levels increased slightly but remained always below 15 mg/100 g.
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P-60
Improved quality of farmed cod
with accelerated maturation
Amble S.S.*, Solberg C.
Bodø University College, Norway
O
ne major bottleneck for successful farming of cod (Gadus morhua) is the early maturation of the fish. So far, commercial
fish farm tries to inhibitor delay the maturation by placing several 600 W light tubes in the net pens from September. This
treatment has been reported to give a delay in the gonad development, resulting in maturing fishes during summertime and
death caused by problems releasing the eggs.
In our region in Northern Norway, there is 24h daylight in the summertime and negligible daylight from November to February.
The temperature in the sea is below 5° from February to the beginning of April, when it gradually increases. During this period
the growth of the cod is negligible.
Instead of suppressing the maturation with the use of continuous high energylight, this experiment was performed to try to
accelerate the gonad development to a period when there is little or no growth of the fish muscle.
Two 5*5*5m net pens were used, with 250 cod (average weight 2.5 kg) in each net pen. One of the net pens was equipped
with a 6W blue-green LED light. The other control group was without any additional light. At start in November 50 fish were
analysed, thereafter 50 samples were taken from each net pen in the beginning of February, Mars, April, May and July. The
proximate composition, texture, pH, body, gutted, liver and gonad weight were measured as well as the total length of the fish
and the development stage of the gonad using a 6 point scale.
The light treated cod was found to have an accelerated gonad development and many of the fish was already matured in
February, gonad index 4 compared with 2 in the control group. In April most of the light treated cod had finish spawning, where
the control group had only started. The gonad weight was found to be at its peak in the control group in April, considerably later
than the peak achieved in the light manipulated group in February. The growth of the gonad has a marked influence on the
growth of the fish, and results in a decreased condition factor and increased water content in the muscle tissue. The condition
factor was lowest in the light manipulated group in April (0.80), when it was still decreasing in the control group and was found
to be 0.78 in May. In July the condition factor was higher in the light group 0.96 compared to 0.91 in the control group. The
muscle water content was highest in the control group in May (82.2%), when it was highest in the light group (82.1%) in April.
The shear force was found to be correlated (r=0.82) to the water content in the muscle tissue. There were only found minor
variation in the post rigor muscle pH.
It was possible to accelerate the maturation of the cod and decrease the time with negative growth. After spawning the light
treated cod recovered faster.
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P-50
Quality evalution of farm-raised Atlantic cod
Skonberg D.1*, Baxter S.1, Brown N.2
1. Department of Food Science & Human Nutrition, University of Maine
2. Center for Cooperative Aquaculture Research, University of Maine
S
everal papers have examined the chemical or sensory qualities of wild caught Atlantic cod, however, due to the fledgling
status of global cod culture, there is currently little information available on product quality of farm-raised cod. Research
conducted with other species has shown significant differences in proximate composition, fatty acid profiles, texture, and flavor
of wild and farmed raised fish. Although Norway and Britain began commercial production of Atlantic cod in 2002, cod culture
is still in the developmental stage in the U.S.
The goal of this study was to characterize various quality attributes and to assess the acceptability of farm-raised Atlantic cod
fillets to American consumers. Product quality was assessed in terms of processing yield, proximate composition, mineral composition, fatty acid profile, instrumental texture and color analysis of the fillets, and sensory testing of the fillets by a consumer
panel. Farmed fish were obtained from Stolt Sea Farms in Easport, Maine. Fillets from wild-caught Atlantic cod were used for
comparison.
The overall quality of the farm raised Atlantic cod was good, and comparable to the quality of the wild caught product. Positive
attributes of the farm raised cod included its lack of parasitic worms and excellent nutritional profile. It had significantly higher
protein, potassium, and phosphorus levels than the wild caught fish, less sodium, and similar levels of omega-3 fatty acids. The
farmed cod fillets had significantly lower «L» values than the wild fillets, and the darker color was detected by the consumer panelists, resulting in a lower acceptability score for color and appearance of the raw product. Although the raw farmed cod fillets
exhibited slightly lower maximum shear values, the difference was not significant and did not affect consumer acceptability
scores for cooked fillet texture. Consumers enjoyed the cooked fillets from the farmed cod and wild cod treatments equally.
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P-52
Relationship among early post-mortem stress and quality
indexes in large size bluefin tuna (Thunnus thynnus)
Parisi G.*, Lupi P., Mecatti M., Zampacavallo G., Poli B.M.
Department of Scienze Zootecniche, Florence University, Firenze, Italy
B
luefin tuna is much appreciated for the preparation of sushi and sashimi by the Japan and USA market. Meat quality parameters, such as colour, consistency and freshness (absence of «hyake») can be significantly affected by an excessive
levels of stress at death time, in this way contributing also to determine the product price. The aim of the research was to evaluate the relationships existing among the harvesting/slaughtering stress indexes and the meat quality parameters in reared
bluefin tuna, starting from the examination of the most important stress and quality parameters changes during the early post
mortem period. Reared bluefin tunas (Thunnus thynnus) (225.7 ± 60 kg b.w.) were killed one by one in sequence with a diver
gun with hunting cartridge. At death, blood was collected and analysed for haematocrit, cortisol, glucose and lactic acid. Immediately after head cutting, gutting, tail cutting on board, the tail was quickly landed, transferred in the laboratory and stored with
ice covering. At 4, 5, 6, 8 and 23 hours after death samples of muscle were extracted for the determination of lactic acid and
ATP and related catabolites - ADP, AMP, IMP, inosine and hypoxanthine. AEC (Adenylate Energy Charge) was also calculated
(ATP+0.5ADP/ATP+ADP+AMP). Muscular pH, temperature and fillet colour were measured at 0, 4, 5, 6, 8 and 23 h after death.
Samples of muscle (in duplicate) of the 3 last killed tunas were taken to determine the isometric contraction force, measured in
continuum from 3 to 24 hours after death.
Tuna muscle showed in the first 24h after death only the first post-mortem phases (pre-rigor and start of the rigor). Tuna’s tail
temperature decreased (R2=0.264**) from 24.8 ± 0.7 °C at death to 8.1 ± 1.4 °C after 23h ice covering. Some stress/quality indexes significantly changed with time after death. pH values decreased (R2=0.538***) from 6.84 ± 0.38 at death to 5.88 ± 0.37
at 23 hours after death, while lactic acid increased to 130.2 ± 20.6 µmol/g. On average ATP decreased with the time of storage,
with values ranging from 4.13 ± 0.67 µmol/g at 4h to 3.54 ± 0.86 µmol/g at 8h, and dropping to 0.18 ± 0.19 µmol/g at 23h after
death. Trunk and tail weights were positively correlated with cortisol (0.824*; 0.892*). The content of ATP and the cortisol level
seem to be related with the size: small subjects seemed to be more resistant to the stress. Muscular stress/quality parameters
pH, ATP, ATP/IMP, and AEC were negatively correlated with lactic acid, IMP, hypoxanthine, L* and Hue. So high levels of the
former parameters and low levels of the second ones should indicate a low stress condition. In the same way low values of L*
and Hue should indicate good quality.
The sequence of killing in the catching and some problems occurred during the catch seemed to influence also some muscular
indexes of stress. The degree of stress would seem to be due to the time of wait before killing. Less stressed tuna achieved
a better price, confirming the importance to kill tuna in properly way both for ethic reason and to preserve the quality of the
meat.
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada
183
Aquaculture and fish supply
P-56
Stress induced changes in sensory properties
and proteome of farmed trout
Godiksen H., Hyldig G., Jessen F.*
Danish Institute for Fisheries Research, Dept. of Seafood Research, DTU, Building 221 Kgs. Lyngby, Denmark DK-2800
S
tress before slaughter is known to affect sensory properties of fish. During delivery of farmed fish to the slaughterhouse the
fish are exposed to several stress factors such as sorting, gathering in ponds and tanks and transport. There is only limited
knowledge about which stress factors are most deteriorative to the quality. Also it is not clear which sensory attributes are most
affected by stress. The aim of this study was to evaluate the sensory properties of farmed trout that have been exposed to
different stress levels. Furthermore two-dimensional (2D) gel electrophoresis was performed on the unstressed and stressed
trout in order to identify stress related marker proteins.
Trout that were unstressed, trout stressed by sorting at the farm and trout further stressed by transport to slaughterhouse were
collected. After slaughter the trout were stored on ice for 3, 5 and 7 days, respectively before sensory analysis that was performed by evaluating attributes of texture, taste and odor.
Results showed that after 3 days of ice storage unstressed trout seemed to be juicier and less fibrous than the stressed trout.
The unstressed trout remained juicy during the whole ice storage period whereas the stressed trout became even more dry
and fibrous during ice storage. Image and data analysis of the 2D gels will be performed to identify proteins that respond to the
different stress levels. The intensity of the stress related proteins will be correlated to the sensory results in order to identify
potential protein markers of stress related quality changes.
At this stage it can be concluded that the level of stress affect the sensory attributes, especially fibrous and juicy.
184
Second Joint Trans-Atlantic Fisheries Technology Conference ~ TAFT 2006
51th AFTC and 36th WEFTA meeting
October 29th - November 1st 2006, Québec City, Québec, Canada