There are three major varieties of cocoa: forastero, criollo, and trinitario.
Forastero accounts for more than 90% of the world’s usage. It is produced primarily in the West African countries of Ghana, Nigeria, Cameroon, and the Ivory Coast.
Cridlo is produced in Venezuela and Central America as well as Papua New Guinea, Java, and Samoa.
Trinitario is believed to be a hybrid of the other two varieties and is produced in Venezuela, Trinidad, Sri Lanka as well as other countries. It is used in the manufacture of certain high quality eating chocolates.
Both the Criollo and Trinitario varieties are considered to have a better flavor than the Forastero. Thus criollo is blended with forastero to improve the flavor.
There are three main types of ingredients produced from cocoa seeds: powder, butter, and extracts.
1) The beans are first cured by fermentation and drying. During this time the pulp surrounding the seeds is decomposed and removed causing the flavor to develop within the seeds.
2) The dried beans are then roasted to the required flavor, aroma, and color which also facilitates the removal of the coating. The roasting temperatures vary from 100-150° C depending on the type of bean and the product to be made.
3) The nib (the seed that is left) contains the butter. It is ground while hot from roasting into a liquid mass called cocoa or chocolate liquor. From this, varying amounts of butter is removed by a hydraulic press.
4) The butter that is left on the filter is cooled and ground to a fine powder under controlled cooled temperatures yielding a fat content of 22% or more. Most powders are produced by the Dutch or alkalized process in which the nib is treated with a warm water solution of up to 3 parts anhydrous potassium carbonate to 100 parts nib (or equivalent amounts of other alkalis). After the alkali is completely absorbed, the nib is processed into the powder. Alkali cocoa is supposed to improve the dispersity, color, and flavor over nonalkalized powder.
Cocoa contains more than 300 volatile compounds including hydrocarbons, monocarbonyls, pyrroles, pyrazines, esters, lactones etc. It also contains about 18% proteins of which only 8% are digestible. Other compounds in cocoa include fats, amines, and alkaloids (including theobromine), caffeine, tyramine, nicotinic acid, free amino acids, tannins, phospholipids, starches, sugars, and minerals (sodium and potassium are high in alkalized cocoa).
Theobromine, the major alkaloid in cocoa, has similar pharmacological activities as does caffeine. Its stimulant action on the Central Nervous System, repiratory system, and skeletal muscles is weaker than that of caffeine but its cardiac stimulant, coronary dilating, smooth muscle relaxant, and diuretic properties are stronger than that of coffee.