Exploring the postbiotic potential of multi-strain pasteurized fermented milk: A metabolomics study

Abstract

The emergence of the postbiotic concept has led to the development of innovative products, such as potential postbiotic fermented milk (PPFM). This study investigated the metabolomics profile of a potential postbiotic (PP) produced by co-fermentation using three probiotic strains. Our findings demonstrated effective mixed cultivation of these strains in pasteurized milk (PM). Non-targeted metabolomics analysis revealed significant differences in the metabolomic profiles between the PP and its raw materials (RM), which consisted of 16.7% skimmed milk powder, 3.3% full-fat soybean flour, and 0.2% sodium citrate. The PP exhibited markedly higher abundances of amino acids and their metabolites; nucleotides and their metabolites; glycerolipids; glycerophospholipids; tryptamine, cholines, and pigments; aldehydes, ketones, and esters; fatty acyls; heterocyclic compounds; organic acids and their derivatives compared to RM. Notably, amino acids and organic acids emerged as prominent metabolites distinguishing the PP from the RM. Pathway enrichment analysis identified six significantly enriched metabolic pathways related to differential amino acid metabolites and three pathways associated with differential organic acid metabolites. Furthermore, targeted metabolomics confirmed the increased abundance of various randomly selected differential metabolites in the PP compared to the RM. These findings underscore the substantial potential of fermented milk as a postbiotic.