The document discusses the basic chemistry and processing of cocoa beans. It describes that cocoa trees produce pods containing beans, and there are three main types of cocoa beans. The beans undergo fermentation, drying, and roasting processes to produce chocolate. Fermentation transforms the pulp and sugars around the bean into acids like acetic acid, and kills the bean embryo to develop flavor. Drying further improves flavor and reduces moisture. Roasting at high heat makes the beans brittle and develops their chocolate flavor. Proper timing and temperatures during each step are necessary to produce high quality cocoa beans.

1. Basic chemistry
changes in Cocoa

2. COCOA:
 The Swedish botanist Linnaeus gave cocoa tree
the name “Theobroma cocoa” or “The food of
GODS”.
 Flowers are produced all the year and resulting
cocoa pods on the same tree.
 A single tree produce 20-50 fruits per year.
 There are three different types of cocoa beans.
They are 1.Criolla cocoas
2.Forastero cocoas
3.Trinitario cocoas

5. Fermentation
Drying
Roasting

6. Fermentation:
• The process has to be carried out in 24-48hrs.
• It takes about 5-7 days also, depends on species.
• Naturally-occurring fungi ( Geotrichum & Candida)
enables the fermentation of the pulp sugars (glucose,
fructose and sucrose) into acetic acid.
• which improves the beans by killing the embryo within
the seed imparting chocolate flavor and reducing
bitterness.
• The pulp around is sticky and needs to be separated.

7. 1st stage:
• The pulp starts loosening from the bean in the 1st
microbial stage.
• The first 48 hours is the anaerobic phase during which the
yeast and the pulp(sugars) surrounding the beans are
transformed into alcohol and carbon dioxide.
• This an anaerobic respiration.
• Process time is 24-36hrs rise in temperature.

8. 2nd stage:
• In the 2nd stage, temperature raises due to the
exothermic reactions to almost 49-54⁰C.
• Lactic acid is formed from sugar and organic
acids.
• As the temperature begins to increase to 40⁰C an
exothermic reaction begins to take place during
which lactic acids begin to form.
• And as the pulp begins to disintegrate, air
begins to penetrate.

9. 3rd stage:
• In the 3rd stage, the temperature rapidly drops and pulp has
drained away as liquid.
• At the end of the 48 hours, the aerobic phase commences, as
the beans are turned, aeration allows strong growth of
Acetobacter , which transforms alcohol to acetic acid.
• The bud within the cacao bean dies from the heat, alcohol,
and acetic acid.
• When the bud dies, important chemical changes begin as
enzymes within the bean itself are released.
• Alcohol is converted into acetic acid in the presence of
oxygen(aerobic respiration)

10. • These are important for the development of the
chocolate flavor.
• The fermentation process also liquefies the pulp. The 6
carbon glucose and fructose sugars are fermented.
• via the pathway,
C₆H₁₂O₆ → C₂H₅OH → CH₃COOH

11. Drying:
Browning of cocoa bean is improved.
Loss of astringency and bitter taste loosening of
shell from bean.
Cotyledons are broken into 2 separate halves.
Moisture is reduced to 6%

12. Roasting:
Dried beans are artfully roasted at 100-150⁰C
for 1-2 hrs. to develop flavor of beans.
The beans become brown in color brittle.
Elimination of excess moisture.

15. Key unit operations in the cocoa supply chain.

16. Sensory Profile….. for Cocoa

17. Effect of process variables:
• Properly fermented beans are brown on the outside.
• Over-fermented cocoa tends to turn a blackish colour
and show areas of mould growth.
• Beans which are under-fermented will have a purple
colour.
• During periods of heavy rain, the cocoa may not be
able to be sun dried sufficiently and mould
contamination will occur.
• Over and under roasting can bring changes in
flavour(bitterness).

18. Chocolate
liquor
Cocoa
butter
Chocolate
powder