Cocoa beans flavor precursors

A more complex flavor development occurs in the production of chocolate. The chocolate beans are first fermented to develop fewer complex flavor precursors upon roasting, these give the chocolate aroma. The beans from unfermented cocoa do not develop the chocolate notes (84—88) (see Chocolate and cocoa). The flavor development process with vanilla beans also allows for the formation of flavor precursors. The green vanilla beans, which have Htfle aroma or flavor, are scalded, removed, and allowed to perspire, which lowers the moisture content and retards the enzymatic activity. This process results in the formation of the vanilla aroma and flavor, and the dark-colored beans that after drying are the product of commerce. 

Although flavor precursors in the unroasted cocoa bean have no significant chocolate flavor themselves, they react to form highly flavored compounds. These flavor precursors include various chemical compounds such as proteins, amino acids, reducing sugars, tannins, organic acids, and many unidentified compounds. 

The predominant bacteria were A. pasteurianus, and a novel species was found and named A. ghanensis (Cleenwerck et al. 2007), A. senegalensis (Camu et al. 2007 Ndoye et al. 2007), and A. fabarum (Cleenwerck et al. 2008). Acetic acid can penetrate the cocoa beans, kill the embryo, and decompose their internal structure to form flavor and color development. Thus, acetic acid bacteria have an important function during cocoa bean fermentation that contributes to the formation of cocoa flavor precursors and the control of the cocoa bean fermentation process. 

Hansen, C.E., Manez, A., Burri, C. and Bousbaine, A. (2000) Comparison of enzyme activities involved in flavor precursor formation in unfermented beans of different cocoa genotypes. J Sci Food Agric 80, 1193-1198. 

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