Presence and variation of γ-aminobutyric acid and other free amino acids in cocoa beans from different geographical origins

gamma-Aminobutyric acid (GABA) is a non-protein amino acid coming from the enzymatic alpha-decarboxylation of glutamate. It is a neurotransmitter that has recently raised some interests for its health effects: hypotensive, diuretic, tranquilizer and diabetes preventing agent. Regarding GABA content in cocoa, rare information is available in literature, so the aim of this study was to provide an overview on the GABA content in fermented and dried cocoa beans from different geographical origins (Africa, Central/South America, Asia and Oceania). GABA and other free amino acids were analyzed by HPLC/FLD after derivatization with 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate. Results showed that cocoa beans are an excellent source of GABA and its content is extremely variable as a function of the geographical origin, ranging from a minimum of 31.7 mg/100 g for Grenada beans to a maximum of 101.2 mg/100 g for Ecuador beans. (C) 2014 Elsevier Ltd. All rights reserved.