Effect of polyphenol and pH on cocoa Maillard‐related flavour precursors in a lipidic model system

Summary Polyphenol and pH influence the flavour quality of cocoa beans during roasting. Amino acids and reducing sugars are flavour precursors in cocoa beans, which develop into cocoa‐specific aroma through Maillard reactions during roasting. A central composite design was applied to determine the combined effect of polyphenol and pH on the flavour precursors during cocoa roasting at 120 °C for 45 min using a lipidic model system. Polyphenol was added at 40, 80 and 120 g kg−1and pH was adjusted to 4.5, 6 and 7.5. The response surface methodology revealed that a lower concentration of amino acids and reducing sugars was obtained at higher polyphenol concentration (120 g kg−1) and lower pH value (4.5). Based on the constraints set, the best polyphenol concentration of 43–58 g kg−1and pH of 7.0–7.5 was found to be optimum for the formation of flavour precursors in this lipidic model study.