Identification and taste presentation characteristics of umami peptides from soybean paste based on peptidomics and virtual screening.

This research concentrated on soybean paste fermented with Tetragenococcus halophilus, employing peptidomics and machine learning methodologies to screen for novel umami peptides. Taste characteristics of umami peptides were evaluated through sensory evaluation and electronic tongue analysis. The mechanism of taste presentation of the umami peptides was investigated through T1R1/T1R3 molecular docking techniques. Four peptides were identified: LLYGKVVKKT, DKKVSVGT, TRKQALLN, and QKNSHQ, with umami thresholds ranging from 0.02 to 0.14 mmol/L. Hydrogen bonds and electrostatic interactions are the key forces between umami peptides and receptors, and the length of hydrogen bonds is between 2.94 and 3.30 Å. Molecular docking analyses revealed that electrostatic and hydrogen bonding interactions are crucial, with ARG 248 and ALA 282 serving as key binding sites on T1R1 and T1R3 receptors, significantly influencing umami intensity. These findings aid in further understanding the flavor properties of umami peptides in soybean paste.