Fermentation, Drying and Polishing of Cocoa
Fermentation of Cocoa
During this process the mucilage round the seed is removed the purple pigment diffuse through the cotyledons. The precursor of the chocolate flavour is produced and astring disappears. Fermentation is done in heaps or in baskets covered with banana leaves. The beans are left for 4 to 9 days. Fermentation can also be done in wooden sweat boxes which are 3 deep. 6′ in length and 5′ width. Holes are provided at the base of boxes for aeration and free drainage of the sweatings fermentation takes 6 to 7 days. During this process beans are transferred to second box after 2 to 3 days and then to third box after another 2 to 3 days and remain therefore further 2 days.
During the first 36 hours of fermentation, the temp, rises to about
6 F – 32
960 F (360C) — = ———
There is very limited aeration, under these conditions yeast develops and convert the pulp sugar into alcohol and CQ2. Temperature, then increases to about 1200F (49°C). As the pulp cell collapses, air enters the mass and there is rapid oxidation of the alcohol to acetic acid by acetobaeter bacteria. The beans are killed mainly through the penetration of alcohol and acetic acid into the cotyledon issues. Diffusion from the polyphenol storage cells then occurs followed by enzyme attack on the anthocynins. Proteins are hydrolysed to amino acids. The colour of the tissues become progressively paler and then pale brown. The brown colour deepens. The cotyledons shrink from the testa and separate. There is a gradual development of aroma and flavour and loss in astringency.
Drying of Cocoa
After fermentation, the beans are spread on mates, trays or drying floor and dried in the sun for uniform drying stirring is done. Drying takes about 7 days. During drying the enzymic action continuous and the moisture content reduced from 56 to 6%.. During the process of fermentation and drying the loss in weight is 55 to 64%.
Polishing of Cocoa:
The beans may be polished mechanically or by feet, the latter is known as. ‘Dancing the cocoa in Trinidad’. The beans are wetted and trampled with bare, feet, care being taking not to crush the beans but rather to rub one against the other.