Low molecular weight peptides in tauco, a fermented soy product, associated to umami taste through peptidomics‐sensomics approach

Summary Umami peptides from ultrafiltration fractions of tauco have never been revealed yet. This study's objective was to determine umami peptides by peptidomics‐sensomics approach followed by molecular docking on the ultrafiltration fractions of tauco with MWs <3 kDa from different regions of Indonesia. Sensory evaluation by taste dilution analysis to determine umami intensity and peptide identification by HR‐LC–MS/MS were conducted. Seventeen peptides were revealed to be associated with the intense umami taste of tauco fractions, having molecular weights of 1106–1760 Da. The molecular mechanism and binding energy affinity of the peptides to umami receptor T1R1/T1R3 heterodimer through molecular docking confirmed the result. Peptides IPVNKPGRF, DVFRAIPSEV, and DVTDVTGDRGVTVT are 3 of the 17 identified peptides which have the lowest binding energy to umami receptor T1R1/T1R3 at −9.4, −9.2, and −9.1 kcal mol −1 , respectively. In addition, the molecular docking results indicated that His145, Asn68, Val277, and Ser67 of taste receptor type 1 member 3, T1R3 subunit, play critical roles in the binding with identified umami peptides by forming hydrogen bonds and hydrophobic interaction.