ABSTRACT
The cocoa bean consists essentially of a shell (testa), which represents 10-14% dry weight of the cocoa bean, and the kernel or cotyledon (8690%), which confers characteristic flavours and aromas of chocolate (Osman, Nazaruddin, and Lee 2004; Afoakwa 2010). The minimum average bean size is 1 g (Nair 2010). A transverse section of a cocoa bean showing two cotyledons (nibs) and a small germ or embryo, all enclosed in a leathery seed coat or testa is shown in Figure 9.1, The cotyledons contain about one-third water and one-third fat (cocoa butter) and the remainder consists of phenolic compounds, starch, sugar, theobromine, non-volatile acids and many other components in small concentrations. The cotyledons of the Criollo varieties are normally white in colour, those of the Forastero dark purple, whereas Trinitario have white to deep purple cotyledons (Afoakwa and Paterson 2010). The cotyledons have two main functions, as the storage organs containing nutrients for the development of the seedling and as the premier leaves of the plant when the seed germinates (Nielsen 2006; Nair 2010; Afoakwa 2010).
