Impact of post-harvest processing and roasting conditions on the physicochemical properties, phenolic compounds, and antioxidant capacity of cocoa beans from the Brazilian Amazon

Abstract

Interest in cocoa (Theobroma cacao L.) and its derivatives has grown mainly due to the high concentration of phenolic compounds (PC), which exhibit potentially beneficial effects on human health. Brazil is the sixth-largest producer of cocoa beans worldwide, with the Amazon region, particularly the state of Pará, playing an increasingly significant role in this production. This study evaluated the effects of pod storage, fermentation time, type of drying platform, municipality and roasting time and temperature on cocoa beans from the Brazilian Amazon. Parameters such as moisture, pH, and cut test were assessed, and individual phenolic compounds were quantified by HPLC-DAD. The Folin-Ciocalteu assay was used to evaluate total phenolic compounds (TPC), and antioxidant capacity was measured using DPPH and ORAC methods. Results showed that the phenolic content and antioxidant capacity of the beans are influenced by the municipality of origin. Fermentation time was the pre-processing condition that most significantly influenced the physicochemical and bioactive properties of the beans, causing reductions of 55–76% in individual phenolic compounds and 43.5–60.57% in antioxidant capacity after seven days. While roasting tends to degrade most phenolic compounds, catechin can form or stabilize at higher temperatures and longer roasting times.