Cross-modal saltiness perception in MRPs derived from hydrolyzed Coprinus comatus protein: linking sulfur-containing volatiles to saltiness-enhancing capacities.

Abstract

Thermally processed edible mushroom protein hydrolysates exhibit saltiness-enhancing properties. Previous studies have primarily attributed this effect to either an increased content of umami substances or basic taste interactions; however, the potential contribution of odor-induced saltiness enhancement (OISE) through olfactory participation remains underexplored. This study investigated the accumulation of flavor compounds throughout thermal processing of a Coprinus comatus peptide-xylose-cysteine model system. Potential odorants with OISE capacities were screened by correlating the concentrations of sulfur-containing volatiles with the perceived saltiness intensities of Maillard reaction products (MRPs) obtained under different processing conditions. The impact of reaction time on flavor development exhibited distinct phase-dependent characteristics. The consumption of free amino acids primarily happened during the initial stage (0-60 min), while extended processing (90-150 min) promoted the controlled generation of sulfur-containing volatiles with meaty flavors, such as 2-methylthiophene, 2-pentylthiophene, 5-methyl-2-thiophenecarboxaldehyde, and bis(2-methyl-3-furyl) disulfide. Correlation analyses further revealed that sulfur-containing species, particularly thiophenes (2,3-dimethylthiophene and 2-pentylthiophene) and thiols (2-methyl-3-furanthiol), showed strong associations with perceived saltiness intensity (r > 0.9), underlying their cross-modal taste modulation capacities through OISE. This chemosensory mapping enables targeted sodium reduction while decoding OISE mechanisms in thermo-processing systems.