Identification of potential key metabolites in synbiotic yoghurt made with probiotic Saccharomyces cerevisiae var. boulardii CNCM I-745 and prebiotic inulin by non-targeted metabolomics analysis

Probiotic yeasts are attracting widespread attention due to their unique therapeutic properties and benefits to human health, but how they function in food system has been much less studied. Here, yoghurt was prepared using probiotic Saccharomyces cerevisiae var. boulardii CNCM I-745 with and without addition of prebiotic inulin, and the metabolic changes in yoghurt during 28 days of storage at 4 °C were analyzed by non-targeted metabolomics method. Potential functional metabolites that were differentially expressed in the synbiotic yoghurt added with inulin were identified, including hydroxyisocaproic acid, indolelactic acid, α-lactose, pelargonic acid, trehalose, 2-isopropylmalic acid, maltitol, D-glucuronic acid, raffinose, uric acid, and maltohexaose. These differential metabolites might play an important role in improving probiotic yeast survival and synbiotic yoghurt functionality through relevant metabolic pathways. This study promotes comprehension on the metabolic properties of the probiotic yeast in yoghurt with significance in exploring its applications in synbiotic dairy products. [Display omitted] •Metabolic differences were found between the probiotic and synbiotic yoghurt.•Survival of probiotic yeast was explained by its metabolites during cold storage.•Untargeted metabolomics specified that inulin could alter metabolite levels.•Relatively higher contents of key metabolites were identified in synbiotic yoghurt.•Key pathways were involved in survival of probiotic yeast in synbiotic yoghurt.