Chemical profile and sensory evaluation of Cantonese raw soy sauce to reveal the association between taste characteristics and chemical composition

The taste characteristics of soy sauce are closely related to its chemical composition. In this study, raw soy sauce was analyzed by silica gel column chromatography (SGCC) and the fractions were evaluated by a sensory trained panel. Based on the sensory results, the representative sensory-guided fractions were further analyzed by untargeted metabolomics technology. Moreover, we carried out the correlation between the taste characteristics and chemical composition of these fractions. The yield of umami-taste fractions was 62.50%. Fractions F-2 (eluted by ethyl acetate) and F-4 (eluted by 90% ethanol) were significantly associated with the bitter and acid tastes, and the umami and salty tastes, respectively. They showed better ratings than other fractions. Seventeen compounds were identified through chemical profiling and they were classified into four categories, including amino acids and derivatives, organic acids, carbohydrates and conjugates and the others. It revealed that compounds of different categories in F-2 and F-4 had different correlations with taste characteristics, which provided theoretical research for the study of soy sauce flavor. In conclusion, this study is beneficial to boost product competitiveness in the marketplace, improve industry standardization, and drive technological innovation in the industry.