Abstract

The presence of insoluble-bound phenolic and insoluble-bound alkaloids (e.g., theobromine, trigonelline, nicotinic acid, and paraxanthine) in raw cocoa nibs and husk is reported for the first time. Cocoa nibs contain higher amounts of insoluble-bound alkaloids than the husk, while the opposite is observed for the phenolics. The total protocatechuic acid, the main phenolic acid present in both feedstocks, was approximately up to 8 times higher, considering both fractions and comparing the results using common procedures that do not consider the insoluble-bound components. Furthermore, the insoluble-bound fraction contributed up to 40% of the antioxidant properties of the tested materials. A reliable database for the phenolic content of foods is necessary to assess the effects of their intake on various biological parameters. Therefore, by demonstrating that some bioactives of cocoa and its processing by-products have largely been underestimated, this study provides crucial information that would contribute to better understanding of the chemistry of cocoa products and their potential health benefits.