Unraveling the saltiness-enhancing effect of aroma compounds in soy sauce via integrated sensomics and molecular docking approaches.

This study combined sensomics strategies and molecular docking to systematically identify and validate key compounds enhancing saltiness in soy sauce, elucidating their binding mechanisms with saltiness receptors. Gas Chromatography-Olfactometry-Mass Spectrometry (GC-O-MS) revealed nine key compounds were identified for their saltiness-enhancing effects, which were further confirmed by Odor-Induced Saltiness Enhancement (OISE) values and Time-Intensity (TI) analysis. Notably, 2,3,5-trimethylpyrazine (2,3,5-TMP) and methionol significant enhanced perceived saltiness in a 0.6% NaCl solution compared to the control (p < 0.05). Furthermore, the saltiness-enhancing effect of these compounds was most pronounced in the 0.6% NaCl solution, compared to 0%, 0.3%, and 0.9% NaCl solutions (p < 0.05). Molecular docking suggested that increased perceived saltiness was likely mediated by the reduction in binding energy, alongside the formation of hydrogen bonds and hydrophobic interactions. This work highlights aroma compounds as a strategy for reducing sodium content in soy sauce while preserving flavor, offering implications for healthier design.