Nutritional evaluation, characteristic component differences and non-targeted metabolomics analysis of traditional fermented glutinous Rice in four Chinese provinces

This study aimed to compare the nutritional characteristics, antioxidant activity, and flavor differences of traditional fermented glutinous rice from four regions of China, and to elucidate the underlying metabolic mechanisms using metabolomics. Physicochemical assays, HPLC, GC–MS, and LC-MS analyzed five samples (HB_MPP, SC, JS, GZ_LYM, SWJD). Significant differences in antioxidant capacity and amino acids were found, with lysine as the first limiting amino acid. Dominant organic acids were lactic, malic, and fumaric acids. Forty volatile compounds (mainly esters, alcohols, acids) were detected, with phenylethanol, ethyl hexadecanoate, and ethyl decanoate as key flavor markers (VIP ≥ 1). Metabolomics identified 3027 metabolites, dominated by lipids (27.59%) and organic acids (26.99%). Key pathways included plant secondary metabolite biosynthesis and amino acid metabolism. This first multi-omics comparison highlights regional characteristic bases, aiding traditional fermented food quality evaluation and industrial application. • Multi-technique analysis identifies distinct regional differences in 5 Chinese fermented glutinous rice. • Lysine (first limiting amino acid), phenylethanol (VIP = 2.5380) and lactic/malic/fumaric acids are key markers. • Untargeted metabolomics identifies 3027 metabolites and 3 core differential pathways. • SWJD exhibits highest antioxidant activity via phenolics, guiding functional raw material optimization. • This work clarifies fermented glutinous rice regional basis, supporting its quality evaluation and industrial upgrading.