acid taste

Acceptability of improved hibiscus drinks by
Senegalese consumers
Monteiro, M.J.P. a, Cisse, M. b , Fliedel, G. c, Bechoff, A. d, Costa, A.I.A.
Boucher, M. c, Ayessou, N. b, Pallet, D. c, K.Tomlins d, Pintado, M.M. a
a
CBQF Laboratório Associado, ESB UCP - Porto, Portugal.
C CIRAD - Montpellier, France.
D NRI, University of Greenwich - Chatham, United Kingdom
a,e,
B
ESP, Université Cheik Anta Diop - Dakar, Senegal.
e CUBE - Católica Lisbon School of Business and Economics - Lisboa,
Portugal.
.
Results and discussion
Summary
• Infusions and syrups made from calyces of Hibiscus var. sabdariffa are commonly
consumed in West African countries, particularly in Senegal, where they are broadly
known as jus de bissap.
• Consumer acceptance was positive for all samples, but differed significantly (p ≤ 0.01)
between them. Mean overall liking ratings show that all new drinks were liked slightly to
moderately, as well as better appreciated than the traditional infusion.
• The sensory quality of a traditional Senegalese hibiscus infusion (CTi) and three new
hibiscus drinks developed by the African Food Tradition Revisited by Research (AFTER)
project – an ultra-vacuum concentrate (UVc), an improved syrup (REs) and an improved
infusion (REi) - was evaluated by a consumer sample (n=150) in Dakar in October and
November 2013.
• Three clusters of Senegalese consumers were identified based on overall liking ratings: C1 Traditional infusion dislikers (19%), C2 - Improved infusion dislikers (25%), C3 - Overall likers
(56%). Cluster 3 size can be explained by the popularity of hibiscus drinks in Senegal and the
effectiveness of the new production processes developed by AFTER.
• Mean overall liking ratings show that all new drinks were liked slightly to moderately, as
well as better appreciated than the traditional infusion. Derived clusters were highly
related to participants’ evaluations of sensory attributes, namely of sweet, acid and bissap
taste intensities. New drinks were also characterized as traditional, healthy and nutritious.
Materials and Methods
C1-Traditional infusion
dislikers (19%)
9
8
7
7.07a
7.07a
6.65b
6.68a
6.96a
C2-New Infusion
dislikers (25%)
C3-Hibiscus drinks
likers (56%)
7.17a
7.01a
6.85a,b
6.52b
6.87a
6.21a
6.19c
5.65d
6
Overall liking
• Multi-Factorial Analysis (MFA) plot shows a good agreement between Just-About-Right
(JAR) ratings and Check-All-That-Apply (CATA) descriptor choices across all samples.
All respondents
5.08b
5
3.82b
Mean
consumer
acceptance of Hibiscus
drinks.
Error bars represent the
confidence interval of the
mean (p=0.95).
Different superscripts
within a cluster indicate
significant differences
according Tukey’s HSD (p
≤ 0.05).
3.79c
4
3
2
1
• Consumers of hibiscus drinks were non-probabilistically recruited at four Dakar locations,
according to their willingness and availability to participate in the study (n=150). Their ages
ranged between 18 and 73 years old (average 34); 61% were male, 88% were Senegalese or
long-term Senegal residents and 81% consumed hibiscus drinks at least several
times/month.
• Tasted samples were prepared from a mixture of dried calyces (50:50 ‘Koor’:’Vimto’ Hibiscus
cultivars) grown locally.
UVc REs REi CTi
UVc REs REi CTi
UVc REs REi CTi
UVc REs REi CTi
• Clusters were highly related to participants’ evaluations of sensory attributes, namely the
sweet, acid and bissap taste intensities of different samples. Significant age and gender
effects on JAR ratings were uncovered, indicating a penalty for weaker sweet and stronger
acid taste intensities by women and younger participants.
REi Acid taste
REi Sweet taste
REi Bissap taste
REi Bissap odour
REi Colour
• Sample acceptability was assessed by overall liking ratings provided on a 9-point hedonic
scale. Hierarchical cluster analysis (Ward’s method) was used to segment consumers
accordingly. Sensory attributes’ - colour, bissap odour, bissap, sweet and acid taste –
intensities, relatively to participants’ ideal level, were measured by attribute ratings provided
on a 3-point JAR scale. These ratings were related to overall liking using a Weighted Penalty
analysis. XLSTAT (Addinsoft) software was used to analyse data.
RES
Acidity TW
Bissap taste TW
Bissap odour TW
Red colour TW
Swetness TS
CTi Acid taste
CTi Sweet taste
CTi Bissap taste
CTi Bissap odour
CTi Colour
• Sensory profiles were obtained with CATA questions. These entailed 21 sensory or hedonicoriented descriptors drawn from two previous focus groups with Senegalese hibiscus
drinkers. Seventeen terms discriminated significantly (p ≤ 0.05) between samples and were
subsequently submitted to Correspondence Analysis (CA). Individual discriminant term
choices were also related to overall liking by a Penalty-Lift analysis.
REi
Swetness TW
Acidity TS
Bissap taste TS
Bissap odour TS
Red colour TS
REs Acid taste
REs Sweet taste
REs Bissap taste
Res Bissap odour
REs Colour
CTi
Acidity TW
Swetness TW
Bissap taste TW
Bissap odour TW
Red colour TW
Acid taste TS
Bissap taste TS
Bissap odour TS
UVc Acid taste
Uvc Sweet taste
UVc Bissap Taste
UVc Bissap odour
UVc Colour
• MFA was used to relate sample acceptability, sensory attribute intensity and sensory
profiles.
0%
Too weak (TW)
50%
Just-about-right (JAR)
0.2
100%
0.4
0.6
0.8
1.0
Too strong (TS)
Weighted Penalties
JAR evaluations
• CATA CA results show that the four hibiscus drinks were perceived to have highly distinct
sensory profiles. While the traditional drink was mainly described as bitter and acid, and the
improved infusion as astringent and strong in bissap, the improved syrup was mostly
characterised as light in bissap, diluted and syrupy. UVc, the preferred drink, was thought to
have a balanced taste and to be sweet, dark red, appealing, natural and refreshing.
• Hedonic-oriented descriptors’ choices were positively related to overall liking ratings. A
negative penalty-lift was observed for negative sensory descriptors like bitter, astringent and
light in bissap taste.
• The partial representation of samples and centroids in the first two dimensions of the MFA
plot shows a good agreement between JAR ratings and CATA descriptor choices across all
samples.
Conclusions
3
0.6
CTi
Acidic Bitter
JAR
Light Red
• Further studies are needed to assess consumer acceptability and sensory profiling of
improved hibiscus drinks among consumers who are yet unacquainted with such products.
AFTER is currently exploring the market potential of these and other African-tradition based
products in Europe, with encouraging results.
UVc
Sharp odour
CATA
Light Bissap
Diluted
Astringent
Strong Bissap
REi
REs
Syrup Taste
Appealing
O.Liking
0
0
Stimulating
O.Liking
CATA
Natural
Refreshing
JAR
CTi
Good Taste
UVc
REs
O.Liking
Sweet
Dark Red
O.Liking
REi
F2 (33.8 %)
• Moreover, the employment of JAR and CATA techniques uncovered important drivers for
further sensory optimization of the new hibiscus infusion and syrup.
CATA
F2 (25,6%)
• Overall liking assessment were complemented by attribute intensity evaluations and sensory
profiling to provide important insights about hibiscus drinks’ perception and acceptability by
consumers in Senegal. In spite of their varying sensory characteristics, the new drinks
developed by AFTER were all well-liked, also when compared to a traditional local infusion.
JAR
CATA
Balanced Taste
.JAR
-3
-0.6
-1
0
F1 (71.1 %)
1
Projection of Hibiscus drinks and CATA descriptors on the CA plot
This work was supported by National Funds from FCT through project PEst-OE/EQB/LA0016/2013
-3
0
F1 (58,9 %)
MFA plot partial representation
3