From the seed to the cocoa liquor: Traceability of bioactive compounds during the postharvest process of cocoa in Amazonas-Peru

From cocoa harvest to chocolate, different physical and chemical transformation processes take place. In addition to changes in the main components (lipids and proteins), the content and nature of other compounds of nutritional importance, such as bioactive compounds, which are mainly responsible for chocolate being considered a superfood, are also modified. The objective of this research was to evaluate the behavior of bioactive compounds during postharvest processing of three varieties of cocoa harvested in the Amazonas region of Peru. A batch of cocoa was sampled during five stages of postharvest processing (fresh bean, fermented bean, dry bean, roasted bean and cocoa paste), and the content of phenolic compounds (catechin, epicatechin, gallic acid and caffeic acid) and alkaloids (theobromine, caffeine and theophylline) was quantified by ultra high performance liquid chromatography (U-HPLC). The total phenolic content and antioxidant capacity were determined using spectrophotometric techniques; Folin-Ciocalteu and 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical capture. Except for roasting processing, the content of phenolic compounds increased. Theobromine is reduced with fermentation, drying and roasting. Cocoa liquor had a higher content of bioactive compounds, probably because it facilitates availability. Although a slight increase in total phenolic compounds was evident, antioxidant activity decreased to the same degree during postharvest processing of the cocoa bean. In conclusion, postharvest processing of cocoa beans affects their bioactive composition.