Odor-induced saltiness enhancement of volatile compounds screened from duck stewed with chili pepper

Odor-induced saltiness enhancement (OISE) is thought to be a unique salt reduction technique which capitalizes on olfactory-gustatory interaction. Volatile compounds of stewed duck obtained from orthonasal (no-treatment) and retronasal (saliva-treatment) pathways and their capacity on OISE were analyzed by GC-O-MS and molecular simulation in order to ascertain the role of odors in duck stewed with chili pepper on saltiness enhancement. Totally 17 unique volatile compounds were identified in retronasal pathways. Eight salty-congruent volatile compounds were screened from the stewed duck, one of which being E-2-decenal, specific to retronasal volatile compounds following oral enzymatic digestion. These volatile compounds' OISE in NaCl solution was confirmed, and the retronasal pathway effect outweighed the orthonasal one. Molecular docking revealed that volatile compounds interacted with saltiness receptors through hydrogen bonding and hydrophobic force, which may be responsible for its enhanced saltiness. These findings suggest that olfactory pathways and specific odors might simultaneously mediate OISE.