Patrick Edward McGovern ca. 7000-6600 B.C. It was a mixed fermented beverage of rice, honey, and grape and/or hawthorn ("Crataegus pinnatifida" and "C. cuneata") fruit. The laboratory and collaborators began studying some of the most ancient chocolate from ancient Mesoamerica (ca. 1400-1100 B.C.) in 2004 Jars from Puerto Escondido in Honduras were in the shape of the cacao ("Theobroma cacao") pod or fruit, as if to advertise the contents as being a chocolate beverage. The fruit's sweet pulp contains about 15% sugar, which naturally ferments to a 5 to 7% alcoholic beverage. This beverage might have led to the domestication of the tree.
Theobroma cacao until practices changed in the 21st century, the fermented pulp may be distilled into an alcoholic beverage. Each seed contains a significant amount of fat (40–50%) as cocoa butter. The fruit's active constituent is the stimulant theobromine, a compound similar to caffeine. Cacao ("Theobroma cacao") belongs to the genus "Theobroma" classified under the subfamily Byttnerioideae of the mallow family Malvaceae. Cacao is one of 17 species of "Theobroma". In 2008, researchers proposed a new classification based upon morphological, geographic, and genomic criteria: 10 groups have been named according to their geographic origin or the traditional cultivar name. These groups are: