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. PRACTICAL APPLICATIONS: Cocoa (T. cacao) is a rich source of polyphenols with benefits for human health and is the main raw material for elaboration of chocolate. However, the processes to create the desirable organoleptic characteristics of the cocoa beans to produce chocolate affect the concentration of polyphenols and the AA of the beans. Cocoa beans are produced in developing countries in America, Asia and Africa. Nicaragua has become an important producer of cocoa turning it into a popular cash crop and there are not any articles that study the profile and changes in the cocoa from Nicaragua. The results of this paper could be used among the producing cooperatives of cacao in Nicaragua, or even nongovernmental organizations involved in cocoa production, to improve the processing (fermentation and roasting) of cocoa to obtain cocoa beans richer in antioxidants, and therefore increase their nutritional value to create a more competitive product.