Aroma evolution in chocolate production

Chocolate aroma development, indeed, depends on several factors. Several volatile organic compound (VOC) chemical classes contribute to the distinctive chocolate aroma: most develop from aroma precursors, namely reducing sugars and free amino acids, whose production is thermally induced once the fermentation begins and the enzyme pools are triggered. Over 600 VOCs have been reported in the chocolate headspace, of which pyrazines are the most important compounds involved in its distinctive flavor, with a detected pool of circa 80 different molecules belonging to this class. Methyl-, ethyl-esters, and acetates are the most involved VOCs of this chemical class of compounds in chocolate headspace emission. Some derivatives, instead, exhibit an undesirable contribution to the overall chocolate flavor perception: 2-, 3-, and 4-methylphenols have a medicinal and unpleasant aroma, as well as 2-butanol. The drying phase is also important in chocolate aroma evolution, as it is also meant to improve flavor development.