Sensory-Guided Identification and Characterization of Kokumi-Tasting Compounds in Green Tea (Camellia sinensis L.)

The chemical substances responsible for thekokumitaste of green tea infusion are still unclear. Here, we isolated thekokumicompound-containing fractions from green tea infusion through ultrafiltration, and the majorkokumicompounds were characterized as γ-Glu-Gln and γ-Glu-Cys-Gly (GSH) through ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS). The results indicated that peptides and amino acids were essential compounds in the kokumi-enriched fractions for conducting the sense ofkokumi. L-theanine had an enhancing effect on thekokumitaste of green tea infusion, which was confirmed in the sensory reconstitution study. Thus, peptides, especially γ-Glu-Gln and GSH, are the majorkokumicompounds in green tea infusion, which has the potential of improving the flavor of tea beverages.Keywords:kokumipeptides;sensory-guided;identification;characterization;recombination