Multi-omics revealed the formation mechanism of characteristic volatiles in Tibetan yak cheese induced by different altitudes

Abstract

The variation in volatiles, bacteria and metabolites of Tibetan yak cheese (TYC) from different altitudes were characterized with multi-omics to reveal the formation mechanism of characteristic volatile compounds (C-VOCs) in TYC induced by altitudes. 22C-VOCs (odor activity value, OAV > 1) were identified in TYCs, and hexanal, dodecanol, 2,3-butanediol, butyl isobutyate, etc., C-VOCs were confirmed induced by altitude. Lactobacillus, Kocuria, etc., bacteria and benzyl thiocyanate, trehalose, sarcosine, etc., metabolites were screened as the variable bacteria and metabolites for TYCs regulated by altitude, respectively. Pediococcus and carbonhydrates maybe the main contributors for the formation of C-VOCs in TYCs induced by altitudes. The formation of dodecanol, 2,3-butanediol and hexanal maybe derived from sarcosine and EPA, and the generation of butyl isobutyrates maybe originated from 1,6-DP-fructose and threonic acid facilitating by Pediococcus. This research will help us gain insight into the contribution of altitude to the formation of volatiles in TYCs.