FORMATION OF MEATLIKE AROMA COMPOUNDS FROM THERMAL-REACTION OF INOSINE 5'-MONOPHOSPHATE WITH CYSTEINE AND GLUTATHIONE

Sulfur-containing amino acid cysteine (Cys) and tripeptide glutathione (gamma-Glu-Cys-Gly) in its reduced form (GSH) were reacted with the flavor enhancer inosine 5'-monophosphate (IMP) in an aqueous medium. After mixing, the dissolved solution was heated for 1 h at 180-degrees-C. A roasted coffee and cooked meatlike aroma with strong sulfur notes was observed for both reaction masses. The volatile compounds produced in model systems were analyzed by GC and GC/MS. A total of 47 compounds were identified, only 6 of which were non-sulfur-containing compounds. They were mainly thiophenes, thiazoles, sulfur-substituted furans, and polysulfides. The characteristic meatlike compound, 2-methyl-3-furanthiol, was only detected in the reaction between inosine 5'-monophosphate and cysteine. Fewer polysulfides were identified in the model system of IMP-GSH than the model system of IMP-Cys.