COCOA: Harvesting, Post Harvest Management & Its products.
Use in chocolate manufacturing.
Highlighting all necessary steps in transformation of Cocoa from beans to chocolate you desire.
2. INTRODUCTION
• The cocoa bean, also cacao bean or simply cocoa, is the dried and
fully fermented fatty seed of Theobroma cacao, from which cocoa
solids and cocoa butter can be extracted.
• The cacao tree is native to the Americas. It originated in Central
America as well as parts of Mexico.
• Chocolate was introduced to Europe by the Spaniards, and became
a popular beverage by the mid-17th century.They also introduced
the cacao tree into theWest Indies and the Philippines. It was also
introduced into the rest of Asia and intoWest Africa by Europeans.
In the Gold Coast, modern Ghana, cacao was introduced by an
African,Tetteh Quarshie.
3. COCOA POD
A cocoa pod (fruit) has a rough, leathery rind about 2 to 3 cm (0.79 to
1.18 in) thick (this varies with the origin and variety of pod) filled with
sweet, mucilaginous pulp (called baba de cacao in South America) with
a lemonade-like taste enclosing 30 to 50 large seeds that are fairly soft
and a pale lavender to dark brownish purple colour.
Due to heat build-up in the fermentation process, cacao beans lose
most of the purplish hue and become mostly brown in colour, with an
adhered skin which includes the dried remains of the fruity pulp. This
skin is released easily after roasting by winnowing. White seeds are
found in some rare varieties, usually mixed with purples, and are
considered of higher value.
4. HEALTH BENEFITS
In general, cocoa is considered to be a rich source of antioxidants such
as procyanidins and flavanoids, which may impart antiaging
properties. Cocoa also contain a high level of flavonoids, specifically
epicatechin, which may have beneficial effects on cardiovascular
health.Cocoa is a stimulant and contains the compounds theobromine
and caffeine.The beans contain between 0.1% and 0.7% caffeine,
whereas dry coffee beans are about 1.2% caffeine.
The stimulant activity of cocoa comes from the compound
theobromine which is less diuretic as compared to theophylline found
in tea. Prolonged intake of flavanol-rich cocoa has been linked to
cardiovascular health benefits, though this refers to raw cocoa and to a
lesser extent, dark chocolate, since flavonoids degrade during cooking
and alkalizing processes. Short-term benefits in LDL cholesterol levels
from dark chocolate consumption have been found.The addition of
whole milk to milk chocolate reduces the overall cocoa content per
ounce while increasing saturated fat levels.
5. Foods rich in cocoa appear to reduce blood pressure, but drinking green and black
tea may not, according to an analysis of previously published research in the April 9,
2007 issue of Archives of Internal Medicine.
A 15-year study of elderly men published in the Archives of Internal Medicine in 2006
found a 50 percent reduction in cardiovascular mortality and a 47 percent reduction
in all-cause mortality for the men regularly consuming the most cocoa, compared to
those consuming the least cocoa from all sources.
It is believed that the improved blood flow after consumption of flavanol-rich cocoa
may help to achieve health benefits in hearts and other organs. In particular, the
benefits may extend to the brain and have important implications for learning and
memory.
6. Harvesting
Cocoa trees grow in hot, rainy tropical areas within 20° of latitude from the
Equator. Cocoa harvest is not restricted to one period per year and a
harvest typically occurs over several months. In fact, in many countries,
cocoa can be harvested at any time of the year.
Immature cocoa pods have a variety of colours, but most often are green,
red, or purple, and as they mature, their colour tends towards yellow or
orange, particularly in the creases. Unlike most fruiting trees, the cacao pod
grows directly from the trunk or large branch of a tree rather than from the
end of a branch, similar to jackfruit.
This makes harvesting by hand easier as most of the pods will not be up in
the higher branches. The pods on a tree do not ripen together; harvesting
needs to be done periodically through the year. Harvesting occurs between
three and four times weekly during the harvest season. The ripe and near-
ripe pods, as judged by their colour, are harvested from the trunk and
branches of the cocoa tree with a curved knife on a long pole.
7. Harvesting
Pods containing cocoa beans grow
from the trunk and branches of
the cocoa tree. Harvesting involves
removing ripe pods from the trees
and opening them to extract the
wet beans.
Pods are suitable for harvest for 3
to 4 weeks, after which time the
beans begin to germinate. It is
therefore necessary to harvest at
regular intervals as the pods do
not all ripen at the same time. The
frequency of harvesting can have
an effect on yield.
8. Harvesting
The pods are harvested manually by making a
clean cut through the stalk with a well
sharpened blade. For pods high on the tree, a
pruning hook type of tool can be used with a
handle on the end of a long pole. By pushing
or pulling according to the position of the
fruit, the upper and lower blades of the tool
enable the stalk to be cut cleanly without
damaging the branch which bears it.
During harvesting it is important not to
damage the flower cushion which will produce
the flowers and fruits of subsequent harvests,
and care must be taken not to damage the
tree, which would make it easy for parasitic
fungi to penetrate the tissues of the tree.
10. OPENING & EXTRACTION OF PODS
• The pods are opened to remove the beans within a week to 10 days
after harvesting. In general, the harvested pods are grouped together
and split either in or at the edge of the plantation.
• Sometimes the pods are transported to a fermenter before splitting. If
the pods are opened in the planting areas the discarded husks can be
distributed throughout the fields to return nutrients to the soil.
• The best way of opening the pods is to use a wooden club which, if it
strikes the central area of the pod, causes it to split into two halves; it is
then easy to remove by hand the beans. A cutting tool, such as a
machete, is often used to split the pod though this can damage the
beans. Some machinery has been developed for pod opening but
smallholders in general carry out the process manually.
• After extraction from the pod, the beans undergo a fermentation and
drying process before being bagged for delivery.
11. FERMENTATION
• Fermentation can be carried out in a variety of ways, but all methods
depend on removing the beans from the pods and piling them together
or in a box to allow micro-organisms to develop and initiate the
fermentation of the pulp surrounding the beans. The piles are covered
by banana leaves.
• The fermentation process begins with the growth of micro-organisms. In
particular, yeasts grow on the pulp surrounding the beans. Insects, such
as the Drosophila melanogaster or vinegar-fly, are probably responsible
for the transfer of micro-organisms to the heaps of beans.
• The yeasts convert the sugars in the pulp surrounding the beans to
ethanol. Bacteria then start to oxidise the ethanol to acetic acid and then
to carbon dioxide and water, producing more heat and raising the
temperature. The pulp starts to break down and drain away during the
second day.
12. • In anaerobic conditions, the alcohol converts to lactic acid but, as the
acetic acid more actively oxidises the alcohol to acetic acid, conditions
become more aerobic and halt the activity of lactic acid.
• The temperature is raised to 40ºC - 45ºC during the first 48 hours of
fermentation. In the remaining days, bacterial activity continues under
increasing aeration conditions, as the pulp drains away and the
temperature is maintained. The process of turning or mixing the beans
increases aeration and consequently bacterial activity.
• The acetic acid and high temperatures kill the cocoa bean by the
second day. The death of the bean causes cell walls to break down and
previously segregated substances to mix. This allows complex chemical
changes to take place in the bean such as enzyme activity, oxidation
and the breakdown of proteins into amino acids.
• These chemical reactions cause the chocolate flavour and colour to
develop. The length of fermentation varies depending on the bean
type.
14. DRYING
• Cocoa beans are dried after fermentation in order to reduce the
moisture content from about 60% to about 7.5%.
• Drying must be carried out carefully to ensure that off-flavorous
are not developed. Drying should take place slowly.
• If the beans are dried too quickly some of the chemical reactions
started in the fermentation process are not allowed to complete
their work and the beans are acidic, with a bitter flavour. However,
if the drying is too slow, moulds and off flavours can develop.
• Various research studies indicate that bean temperatures during
drying should not exceed 65ºC.There are two methods for drying
beans - sun drying and artificial drying.
17. Products fromHusks & Pulp
• Animal feed from
cocoa husk
• Potash from cocoa
pod husk
• Production of soft
drinks and alcohol
from cocoa pulp
juice (sweetings)
18. Jam and
Marmalade
Pectin for jam and
marmalade is extracted
from the sweetings by
precipitation with
alcohol, followed by
distillation and recycling
of the alcohol in further
extractions.
19. PRODUCTS FROM COCOA BEANS
Once the beans have been fermented and
dried, they can be processed to produce a
variety of products. These products include:
Cocoa Butter
Cocoa Powder
Cocoa Liquor
Chocolates
20. 1)Cocoa
Butter
Cocoa butter is used
in the manufacture of
chocolate. It is also
widely used in
cosmetic products
such as moisturising
creams and soaps.
21. 2)Cocoa
Powder
Cocoa powder can be used
as an ingredient in almost
any foodstuff. For
example, it is used in
chocolate flavoured drinks,
chocolate flavoured
desserts such as ice
cream and mousse,
chocolate spreads and
sauces, and cakes and
biscuits.
22. 3)Cocoa
Liquor
Cocoa liquor is used,
with other ingredients,
to produce chocolate.
Chocolate is used as a
product on its own or
combined with other
ingredients to form
confectionery products.
23. 4)Chocolate
Chocolate is the most popular
food item prepares from
cocoa beans. A large number
of food products involving
chocolates like cakes,
puddings, mousse, chocolate
chip cookies etc are widely
consumed all around the
world.
24. Manufacturing of Chocolates
At the factory the processes
involve in making chocolates are:-
Roasting
Blending
Conching
Tempering
Moulding
25. Roasting
Cleaning, inspecting and sorting of the beans are
at the factory.
Beans are roasted in special equipment
at a temperature of 130−150 °С.
The shells are removed and the cocoa beans are
crushed into cocoa nibs
Nibs are liquefied to form pure chocolate in fluid
form i.e Chocolate liquor.
The liquor can be further processes into two
components: cocoa solids and cocoa butter.
27. Blending
Chocolate liquor is blended with cocoa
butter in varying quantities to make
different types of chocolates.
The different types of chocolates are:
1. Dark Chocolate (sugar, cocoa butter,
liquor & vanilla)
2. Milk Chocolate (sugar, cocoa butter,
liquor, milk powder &vanilla)
3. White chocolate (sugar,cocoa butter,
milk and vanilla)
28. Conching
Intensive mixing at high temperature
A conche (container filled with metal
beads) acts as grinder, also heavy rollers
can be used.
This process produces cocoa and sugar
particle smaller than tongue can detect,
hence smooth fills the mouth.
Length of this process determines the
final smoothness and quality of
chocolates.
29. Tempering
It’s a long and complex
process.
The purpose of this process is
to ensure only best and
stable crystals are present.
This process provides the
best appearance and texture
and creates the most stable
structures.
30. Pouring into heated moulds
Adding extras, if wanted
(like nuts)
The chocolate solidifies
It is then Packed for
shipping.
Moulding
31. Storage
Chocolate is very sensitive
to temperature and
humidity.
Ideal temperature between
15 and 17 C
Relative humidity of less
than 50%
Stored away from other
food items as it can easily
absorb different aromas.