A Family Album - Roast Magazine

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You drink it all the time. You roast it daily. You might
have picked, pulped and hand-sorted at least a few beans. You can judge the
David Roche
difference between a good coffee and an inferior coffee, and can use taste to
and
determine where a coffee was grown and maybe even how it was processed.
Dr. Robert
Osgood
You work with coffee day in and day out. But how well do you really
know the heritage behind it? What do you know about where your coffee
comes from? Not location-wise or farm-wise, but in the botanical sense.
Coffee is a big, extended “family”—from the grandfathers of wild arabica
coffee and robusta to today’s young new hybrids—and there is a great deal
a
family
aLBuM
to be learned from the coffee family tree.
First off, to call “coffee” a family is a bit of a misnomer. It is, in fact, a
genus (Coffea) that belongs to a large family of plants called the Rubiaceae.
Inside the genus are hundreds of species, the best known of which are
the two that are grown commercially: arabica and canephora (robusta).
There are two other coffees grown on a much smaller scale: Coffea liberica
(Liberica coffee) and Coffea dewevrei (Excelsa coffee).
continued on page 38
Getting to
the roots
of coffee’s
plant heritage
photo cou
rtesy of D
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A FAMILY ALBUM: GETTING TO THE ROOTS OF COFFEE’S PLANT HERITAGE (continued)
Ancestry
The industry has been keeping scientific track of coffee since the 18th century, when
Swedish botanist Carl Linnaeus first described arabica coffee. But, before that, where
did it come from? We know that arabica coffee originated somewhere on the plateaus
of Ethiopia and was then transported to what is now Yemen, where it’s been grown
commercially since the sixth century. Later, it was moved to the rest of the tropics, where
it has since become one of the most widely traded of all agricultural commodities.
Another coffee, robusta, originated in central Africa. While this coffee is not as
widely traded as a commodity, it is nevertheless important for use as a coffee beverage
and for blends in espresso. Perhaps even more notably, robusta serves as a source of
genes for coffee breeding by providing disease resistance in crossbreeding programs.
A third coffee—liberica—originated in west Africa. Commonly sold locally, it is also
sometimes used as a rootstock for arabica coffee where nematodes (a type of parasite)
are a problem.
Characteristics
The arabica plant, which is the one most of us think of when we’re talking about
coffee, is a large bush with dark-green oval leaves. It’s different from other coffee
species, having four sets of chromosomes instead of two (technically called a
tetraploid). This is one of the attributes that allows current researchers to distinguish
whether a cultivar comes from arabica stock or robusta stock. The difference in
chromosomes determines coffee traits that affect flavor, body and acidity. These
chromosomes also determine how a coffee interacts with the environment to create
different characteristics.
There are two scientifically recognized botanical varieties of arabica coffee, typica
and bourbon. Additional unclassified varieties are out there but a lot of work remains
to be done before they can be categorized as genetically distinct varieties.
Cultivated variations of typica and bourbon are called cultivars. In fact, often
when we talk about coffee “varieties,” we’re not talking about varieties at all, but
rather cultivars. There are also a number of coffees, including geisha and other
recently rediscovered Ethiopian coffees, which have not yet been determined to
be either varieties or cultivars. Future research, much of it based on chromosome
studies, will enable us to pinpoint the proper terminologies for these coffees.
Some of the cultivars that occurred naturally as mutations are caturra and
pointu. Other cultivars, such as mundo novo and maragogype, originated as a result
of crosses in the field.
Still others—namely catuai, pacamara and the catimors—originated as a result
of breeding programs. Some of these were created in the hopes of resisting diseases
and insects, such as coffee rust, coffee berry disease and the coffee borer. Others
were developed in an attempt to decrease the stature of the bushes to facilitate
picking and increase yield .
Today a few breeding programs are attempting to modify coffee quality,
including caffeine content, acidity, body and flavor. New cultivars are currently
being produced especially in Costa Rica, Ethiopia, Brazil and Hawaii.
What about Flavor?
One thing you’re likely to notice right off the bat is that in this article we don’t
talk about flavor. Why not? Because flavor is incredibly subjective, as we all know.
And that’s not just based on the cupper’s palate, but also on where and how a
variety or cultivar is grown, processed, shipped and roasted. You’ll also notice that
we didn’t cover all of coffee’s many varieties and cultivars in this article; in fact,
there’s a good chance that you won’t find your recent favorite discovery in here.
That’s not because we’re ignoring new or rediscovered coffees, but because we
wanted to stick to the facts of coffee’s botanical nature and many of these new
coffees are still being explored and classified by the scientific community.
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Family, Defined
Genus A category consist
ing of a
group of organisms or spe
cies that are
closely related and thus exh
ibit similar
characteristics. Coffee is in
the genus
Coffea, which also includ
es more than 25
other plant species.
a ra bica cof f ee tr ee
PACAMARA
CATUAI
CATIMORS
Variety
vs. Varietal Most
likely, you’ve seen these wo
rds used
interchangeably, or perha
ps you’ve seen
them used to describe a loc
ation (such
as Java). In truth, there are
only two
generally recognized botan
ical varieties of
arabica coffee: bourbon an
d typica. The
difference between variet
y and varietal is a
grammatical one. Variety
is a noun (thus:
“This coffee’s variety is typ
ica.”), while
varietal is an adverb (“The
differences in
bean size are varietal in na
ture.”).
Cultivar A cultivated
plant that
has been selected for its des
irable
characteristics that distin
guish it from
other plants of the same spe
cies. A cultivar
should have a name that
conforms to the
International Code of No
menclature for
Cultivated Plants (ICNC
P, commonly
called the “Cultivated Pla
nt Code”).
The name must be distin
ct from other
cultivars and when propag
ated, the plant
must retain its desirable an
d different
characteristics. Samples of
cultivars
include caturra, mundo no
vo and ruiru
11. Bourbon and typica can
be also used as
cultivar names, as in red
bourbon.
CATURRA
KENT
MARAGOGYPE
BLUE MT.
cross po
llinating When a
plant cannot pollinate itse
lf and requires
pollen from another plant
to produce a
fruit, such as in robusta cof
fee.
RED
BOURBON
PINK
BOURBON
TYPICA
BOURBON
ARABICA
coffea arabica
Coffea
eugenoides
PACAS
YELLOW
BOURBON
PACHE
COMUM
mutation A sudden dep
arture
from the parent plant in on
e or more
characteristics, caused by
a change in a
chromosome.
When a plant’s
own pollen is used to pro
duce a fruit, such
as in arabica coffee.
MUNDO
NOVO
SAN
RAMON
HYBRID A cross between
members of
the same species (interspe
cific) or genus
(intraspecific). Hybrids are
natural or
deliberately made in breedi
ng programs.
self pollinating
POINTU
MOKKA
HYBRIDO
DE TIMOR
ROBUSTA
Coffea canephora
This coffee tree is read from the bottom up, with the “offspring” coffees listed above their “parents.”
Coffees with a single line leading to them are mutations, while coffees with two lines leading to them are hybrids or crosses.
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A FAMILY ALBUM: GETTING TO THE ROOTS OF COFFEE’S PLANT HERITAGE (continued)
COFFEA
COFFEA ARABICA
The coffee plant was first described by the Swedish botanist Carl Linnaeus. He classified the plant as a member of the Rubiaceae family,
which also includes plants such as the gardenia and the quinine tree. Although technically a shrub, the plant can reach more than twelve
meters in height. There are a number of coffee species, but the two that are most common, and which are used almost exclusively in the
coffee industry, are Coffea canephora (robusta) and Coffea arabica.
Arabica, also known by its botanical name of Coffea arabica,
represents three-quarters of the world coffee production.
New research at the cellular level shows that that Arabica is
probably a relatively recent cross (possibly around 500 years
ago) between Coffea eugenoides and Coffea canephora. The
plant is self-pollinating, which allows it to remain genetically
stable. However, spontaneous mutations have occurred, which
are then cultivated or crossbred with other mutations and
crossbreeds. Typically, the beans are slightly elongated and
greenish-blue.
COFFEA CANEPHORA
Coffea canephora, or robusta, was discovered in the Congo in 1898
and represents about one-quarter of the total world production. The
plant, which is well adapted to warm, humid and low-elevation
equatorial climates, is self-sterile and cross-pollinated, which allows
for greater variability than arabica. The beans are typically small,
rounded and brownish-yellow in appearance. They contain a higher
caffeine content, a lower sugar content and significantly higher levels
of chlorogenic acid than arabica beans.
Free Info #101
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photo courtesy of David Roche
COFFEA LIBERICA is a very tall tree, typically grown in Malaysia and West Africa, which produces large cherries and
beans and has large, waxy leaves. Hybrido de Timor (Hybrid of Timor) is a natural hybrid between robusta and arabica that is best known for its
resistance to coffee rust. It has been used extensively as a parent in breeding programs to produce catimors.
photo courtesy of
Josuma Coffee Co.
photo courtesy of Jeff Taylor
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photo courtesy of David Roche
continued on page 42
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A FAMILY ALBUM: GETTING TO THE ROOTS OF COFFEE’S PLANT HERITAGE (continued)
Be a Genius About Genus…or
Cultivars of Arabica
IS it Family?
It’s been a long time since science class
in high school for most of us, but we prob
ably still remember
trying to learn the natural order of class
ification.
Here it is, from larger to smaller, as a
reminder:
Class of the coffee plant: Dicotyledonea
e
Subclass of the coffee plant: Sympeta
Order of the coffee plant: Rubiales
lae or Metachlamydeae
Family of the coffee plant: Rubiaceae
Genus of the coffee plant: Coffea
photo courtesy
Species of the coffee plant: Coffea arab
Varietals of the Arabica coffee plant:
ica, Coffea canephora
of Geoff Watts
bourbon and typica*
Cultivars of the coffee plant: bourbon
and typica*, caturra, mundo novo, catu
ai
*You’ll notice that bourbon and typica
are listed as both varietals and cultivars.
This is because they actually are both
of the bourbon and typica varieties, and
. There are many cultivars
these cultivars are often just referred to
as bourbon and typica. Just to make thin
gs more confusing.
Free Info #163
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Free Info #161
The cultivars typica and bourbon, both of which are from
arabica, constitute the main genetic base of most of the
world’s cultivated coffee today. Common bourbon coffees
are red, yellow and pink bourbon, pacas and caturra. Typica
has given us coffees such as mokka, kent and maragogype.
There are also a number of crosses, such as mundo novo and
pacamara.
One of the ways to tell the difference between the
cultivars is by looking at the leaves: bourbons have green leaf
tips and typicas have bronze leaf tips. However, the hybrids
of bourbon and typica can have either leaf color following
segregation in the second generation and beyond.
Typica is a base from which many coffee cultivars have
been developed. Typica plants have a conical shape with a
main vertical trunk and many small branches that grow off
at a slight upward slant. They can grow up to 14 feet high.
Bourbon trees have less of a conical shape than typica
but often have more secondary branches. Green leaf tips
are characteristic, as is the arrangement of cherries on the
branch—bourbons tend to develop cherries in clusters along
the branch with significant internodal spacing between
them.
For a detailed look at a variety of
arabica cultivars, turn to page 44
v
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A FAMILY ALBUM: GETTING TO THE ROOTS OF COFFEE’S PLANT HERITAGE (continued)
Typica-based Cultivars
Maragogype
Blue Mountain
Mokka
Mokka (or moka), usually called tall
mokka, is a typica mutation that is
commercially grown in Brazil and
Hawaii. At one time mokka was
thought to be a species but it is clearly
an arabica cultivar, as it has four sets of
chromosomes.
Maragogype (or maragogipe)
is a mutation of typica.
The coffee plant is large,
and produces very large
beans. There is some
controversy over the quality of
maragogype beans.
Kent
Blue Mountain is a typica that is well known for its ability to thrive
in high elevation. Blue Mountain is a location, but it’s also used as
a cultivar name. In fact, it’s a blend of varietals. However, this blend
is planted around the world, and the term “Blue Mountain” is now
used to describe this coffee, no matter where it is grown. There is
also a typica cultivar called guatamala typica in Hawaii which is
indistinguishable from blue mountain by genetic analysis.
Originally discovered in India, kent is a
natural hybrid known for its high yield and
partial resistance to coffee rust.
photo courtesy of Dr. Robert Osgood
Maragogype (left) and Mokka (right)
photo courtesy of Dr. Robert Osgood
continued on page 46
photo courtesy of Dr. Robert Osgood
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A FAMILY ALBUM: GETTING TO THE ROOTS OF COFFEE’S PLANT HERITAGE (continued)
B OURBON - b as e d C u l ti v a r s
Yellow, Red & Pink Bourbon
Caturra
Caturra is a compact mutation of bourbon that was discovered in Brasil. The tree is short, with a thick core, many secondary
branches and large, wavy-bordered leaves. Caturra is either grown as caturra or used as a parent in breeding programs.
Caturra is susceptible to overbearing and often is short lived in field plantings.
Yellow, red and pink bourbon are bourbon
cultivars with a single recessive gene mutation for
ripe fruit color.
Pacas
Pacas is a natural
bourbon mutation
discovered in El
Salvador.
photo courtesy of Dr. Robert Osgood
Pointu
photo courtesy of Jeff Taylor
photo courtesy of Jeff Taylor
Pointu is a mutant of bourbon that produces coffee
with a low caffeine content. It was thought to be extinct
but has recently been rediscovered on Reunion Island,
off the coast of Madagascar.
photo courtesy of Josuma Coffee Co.
continued on page 48
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A FAMILY ALBUM: GETTING TO THE ROOTS OF COFFEE’S PLANT HERITAGE (continued)
HYBRIDS AND CROSSEs
Mundo Novo
Catuai
Catimors
Pacamara
Catimors are the result of crosses between hybrido de Timor
and caturra that was created in Portugal in 1959 as a rustresistant variety. Production is typically high, especially with
proper fertilization and shade. There are a number of catimors,
including colombia, ruiru 11 and others that have been part of
breeding programs in various countries.
Pacamara is the result of breeding pacas and
maragogipe. It has characteristics of both parents in the
first generation.
Catuai is the result of a
cross between mundo
novo and caturra,
characterized by either
yellow or red cherries
(catuai-amarelo or catuaivermelho). Considered
a semi-dwarf, catuai is
short and high-yielding,
with fruit that does not
fall off the branch easily.
Typically needs good
care and fertilization for
best results. There are a
number of catuai cultivars.
Mundo novo is a natural hybrid between typica and
bourbon that was first discovered in Brasil. This strong,
disease-resistant plant has a high production and is a
favored cultivar for Brasilian growers.
photo courtesy of Jeff Taylor
photo courtesy of Tom Owen, Sweet Maria’s Coffee
photo courtesy of Jeff Taylor
continued on page 50
photo courtesy of Dr. Robert Osgood
photo courtesy of Dr. Robert Osgood
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A FAMILY ALBUM (continued)
From
Roots to Fruit
A New Bean is Born
Roots In addition to having long main
vertical roots, coffee trees have taproots and
lateral roots. The taproots are usually very
close to the soil surface, while the lateral roots
can extend more than six feet from the trunk.
The root systems depend, of course, on the
quality of soil, amount of rain, organic matter
and concentration of mineral nutrients.
Free Info #162
Leaves Coffee leaves are dark green and
waxy, with a high shine. They run four to six
inches in length and are either oval or oblong
in shape. Coffee trees have a bilateral leaf
arrangement, meaning that two leaves grow
from the stem opposite each other.
Flower Typically a plant takes two to three
years before it begins producing flowers.
The flowers, which are most often white or
cream in color, grow in clusters in the axils
(the location between a leaf and the stem to
which it is attached). Arabica coffee is usually
self pollinated, and robusta coffee is cross
pollinated. The fresh flowers also have an
intense jasmine-like aroma.
Free Info #155
photo courtesy of Jeff Tay
lor
Fruit Anywhere from six to eight weeks after
the coffee flowers are fertilized, small green
berries, called drupes, appear. The first fruit
structures to form are called pinheads. These
pinheads develop slowly at first, and then
grow rapidly into the immature coffee fruits.
Depending on the climate, there is usually a
four-month period of rapid growth, during
which time the outer skin begins to take on
the shape of the coffee bean. Inside, the beans
are still small, however, as they don’t begin to
grow until about three months after flowering.
By about five months, the beans will almost
completely fill the cherry. At this point, the
cherry will begin ripening. At about eight or
nine months, the cherry is typically full color,
ripe and ready to be picked.
Fa mi ly Tr iv ia
photo courtesy of
Free Info #166
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Jeff Taylor
The word cultivar was coined by
Liberty Hyde Bailey, as a combination
of “cultivated” and “variety.”
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