Effect of fermentation and roasting on the phenolic concentration and antioxidant activity of cocoa from Nicaragua

The aim of this work was to quantify the changes in the total phenolic content (TPC), antioxidant activity (AA) and color hue (CH) of cocoa (Theobroma cacao) beans of group Trinitario from Nicaragua after fermentation and roasting. Cocoa beans with three different grades of fermentation (nonfermented, poorly fermented and fermented) were put under three different roasting temperatures (110, 130 and 150C). The kinetics of the roasting at 130C for 60 min was also studied. After each treatment, TPC, AA and CH were determined. For all the quantified parameters, significant differences (P < 0.05) were found between fermentations and roasting conditions. TPC and AA showed decrease with fermentations and CH showed increases. Roasting decreased TPC except for the 150C treatment, while AA and CH increased. When studying the kinetics at 130C, TPC showed greater reductions with longer treatments while AA and CH showed increases.