Flavor components in the Maillard reaction of different amino acids with fructose in cocoa butter-water. Qualitative and quantitative analysis of pyrazines

Eight amino acids were reacted with fructose in deodorized cocoa butter-water as a model of the Maillard reaction in cocoa beans. Detailed GC/MS analysis of the volatile compounds obtained is reported with particular reference to similarities and differences in the patterns obtained with the amino acids. A quantitative analysis of pyrazines is described. Among the 22 pyrazines detected, 15 had been already reported in roasted cocoa beans. 2-(3-Methylbutyl)-3,6-dimethylpyrazine was formed in the reaction of leucine, while lysine gave three 2-methoxy-3-alkylpyrazines not reported in cocoa.