Enzyme-Assisted Fermentation Using Bromelain and Laccase Enhances Phenolic Profile, Antioxidant Capacity and Bioactive Compounds of CCN-51 Cocoa Beans

Cocoa fermentation is a key post-harvest process that determines the chemical composition and functional quality of cocoa beans. This study evaluated the effect of enzyme-assisted fermentation, using bromelain and laccase, on the phenolic compounds, methylxanthines and antioxidant capacity of CCN-51 cocoa beans from northern Peru. Fresh cocoa beans were fermented in wooden boxes under ambient conditions with different enzymatic treatments based on a factorial design. Samples were collected at 0, 2, 4 and 6 days of fermentation to determine total phenolic content (TPC), total flavonoid content (TFC), antioxidant activity (DPPH, ABTS and FRAP), and the concentrations of theobromine, caffeine, catechin and epicatechin by UHPLC-MS. Significant changes in phenolic composition and antioxidant activity were observed during fermentation (p < 0.05), with higher values in enzyme-treated samples, particularly at day 4. Principal component analysis indicated that phenolic compounds and antioxidant activity were the main variables responsible for sample differentiation. Response surface methodology showed that bromelain had the strongest influence on most responses. Optimization using a desirability function predicted an optimal enzymatic condition of 52.19 g of bromelain and 18 g of laccase per 5 kg of cocoa beans to maximize bioactive compounds. These findings highlight that enzyme-assisted fermentation is a promising strategy to enhance cocoa functional quality.