Abstract:Rice sour soup is a traditional fermented food with sour taste, unique flavor and various health functions, which is formed by spontaneous fermentation with glutinous rice flour. To understand the effect of flavors on the taste of rice sour soup, we systematically evaluated the taste of rice sour soup and analyzed the taste-related compounds and using untargeted metabolomics techniques based on gas chromatography time-of-flight mass spectrometer (GC-TOF-MS ) coupled with derivatization and ultrahigh-performance liquid chromatography coupled with QExactive HF-X mass spectrometry (UHPLC-QE-MS ). The results showed that 49 different metabolites were identified based on VIP (variable importance of projection) > 1.00 and P < 0.05, including 27 organic acids, four amino acids, nine carbohydrates, three alcohols, four aldehydes and two esters. And then, the metabolite pathways related different metabolites were revealed that there were ten significant differential metabolic pathways (Impact > 0.01, P < 0.05). Finally, the correlation analysis of different metabolites and taste indicators of sour soup revealed that there were the statistically significant positive relationships between fatty acids (oleic acid, linoleic acid, and myristic acid), organic acids (lactic acid, tartaric acid, malic acid, succinic acid) and the sour taste; between isomaltulose, lactose, glycine and umami; between erythritol, glycerol, threonine and palatability; between lactulose, ?琢-D-glucose, mullein, maltotetraose, N-acetyl-DL-aspartic acid and aftertaste; between succinic anhydride, p-hydroxyphenyl lactate, lactose and mouthfeel richness. Therefore, this study analyzed the relationship between flavors and taste of fermented rice sour soup, and laid an important theoretical foundation for the stability and improvement of sour soup quality in industry.