Effects of continuous enzymolysis on the umami characteristics of Lentinula edodes and the flavor formation mechanism of umami peptides

The purpose of this study was to explore the effect of continuous enzymolysis on the umami characteristics of Lentinula edodes and illuminate the umami mechanism of peptides. The results indicated that the continuous enzymolysis extracts (LFTE) of L.edodes had higher umami intensity and palatability than the water extracts (LWE). 1H NMR and LC-MS/MS were used to evaluate taste metabolites and peptide profiles. Among the identified peptides, LPGVAE, LDELEK, DVELSK, LPDEAR, and TTLPDK with high umami scores which threshold in the range of 0.091-0.371 mmol/L were screened by iUmami-SCM and BIOPEP-UWM, and further verified by sensory evaluation. The results of molecular docking suggested that Ser148, Asn150, Ser276, Ser278 of T1R1 and Asn68, Val277, Ala302, Ser306 of T1R3 played a key role in the umami peptides docking. The study revealed continuous enzymolysis of L.edodes could obtain more umami substances and umami peptides, which laid a foundation for researching flavor substances and developing flavor products from L.edodes.