Chocolate

What cocoa is

Chocolate is a food made from roasted and ground cocoa beans. Cocoa beans are the processed seeds of the cacao tree, Theobroma cacao. The cacao tree is a small evergreen tree of the Malvaceae family, 6-12 m tall. The cacao pod contains 20 to 60 seeds, usually called "beans", embedded in a white pulp.

From bean to flavour

In its raw state, cocoa beans do not possess any of the flavors associated with chocolate. The beans must undergo fermentation following harvest, where bacteria and natural yeast metabolize sugars and proteins within the bean and generate chemical precursors that are important to aroma compound formation. Fermentation usually takes place over 4 to 6 days. Once fermentation is complete, the beans are dried to reduce water content from 60% to 8% by weight. In drum roasters, the high temperatures further reduce the water content to 2% by weight and facilitate Maillard chemistry, where sugars react with amino acids formed during fermentation to produce the aroma compounds. Such compounds include Strecker aldehydes and pyrazines, both aromatic classes contributing to chocolate flavor. To finish chocolate, the beans are deshelled and ground into a fine mass, which is refined with added sugar, cocoa butter and emulsifier in a process called conching. The molten chocolate is heated to 80 °C during conching, which may last 72 hours.

Chemistry

More than 600 flavor compounds of cocoa beans and cocoa products have been identified. Pyrazines are the main class of heterocyclic volatiles formed by the Maillard reaction during roasting, and key components of cocoa flavor and aroma. About 80 pyrazine compounds contribute to the overall cocoa flavor. The share of 2,3,5,6-tetramethylpyrazine rose from 0.5% in the cacao beans to 2.69% in the cocoa powder. Cocoa also holds polyphenols, which give chocolate its distinct bitterness. Theobromine is the principal alkaloid of Theobroma cacao, and cocoa beans naturally contain approximately 1% theobromine. Pure theobromine is an odorless white crystalline powder with a bitter taste.

Supply

Cocoa beans for most chocolate are grown in West African countries, particularly Ivory Coast and Ghana, which contribute about 60% of the world's cocoa supply. In 2023, world production of cocoa beans was 5.6 million tonnes, led by Ivory Coast with 42.5% of the total. Other major producers were Ghana (11.7%) and Indonesia (11.5%). Three main cultivar groups of cacao beans are recognized: Forastero, Criollo and Trinitario.