1.1 The crop and its origin

Having probably originated in the upper Amazon, the cacao tree Theobroma cacao was also extensively cultivated in Central America, with archaeological evidence of cocoa bean processing more than 1,000 years BCE, around Chiapas and Gulf of Veracruz in Mexico. 

Following its well-known introduction to the Spanish court by the conquistadores in the 1540s, knowledge of cocoa rapidly spread throughout Europe in the following decades. By the 19^thcentury, introductions of the crop had been to scattered tropical locations in other continents, with Tetteh Quashie introducing cocoa to the African mainland from Fernando Po (now Bioko island) in 1876.

The wider international trade and the popularity of chocolate products followed during the 20^th century.

The cocoa plant itself belongs to the genus Theobroma – of which there are about 20 species, all from Southeast Mexico to Tropical South America; it is now placed in the subfamily Byttnerioidea (it was placed previously in the "Sterculiaceae"). 

These and other taxa have been relegated to subfamilies in the cotton/mallow family Malvaceae: of which there are nearly 250 genera, with a world-wide distribution and an especially high diversity in tropical areas. 

Modern plant breeders recognise about ten major cocoa clades [1], but traditionally the trade has considered three main types of cocoa, with which most practitioners remain familiar [2]:

These terms required revision because of long-standing debates about the genetic background of the planting materials, with arguments about the provenance of and strategies for optimising production. 

For example, 'Nacional' from Ecuador is a well-known, fine flavoured variety but probably an Amazonian (Forastero) type tree. 

There is controversy as to whether this "national treasure" should be grown in preference to CCN-51, which has a higher production, tolerance of direct sunlight and probably disease resistance.