Interaction differences between selected sweet-fragrant aroma compounds and different salivary proteins: Effects of molecular structure.

The binding and activation of sweet-fragrant aroma compounds to sweet receptors in the oral cavity is considered to be an important mechanism for aroma to enhance sweet perception. However, the role of salivary proteins is ignored in this process. Therefore, this in vitro study systematically investigated the interactions between three key salivary proteins-mucin, α-amylase, and lactoferrin-and aromas. The results suggested that the interaction behavior was jointly determined by the molecular structure of proteins and aromas. Mucin exhibited a stronger adsorption capacity for aroma than α-amylase and lactoferrin. Salivary proteins showed relatively strong binding affinity for ethyl cinnamate and vanillin, but weak binding affinity for 3-methyl-2-cyclopenten-1-one, isoamyl acetate, and γ-decalactone. Hydrophobic interactions and hydrogen bonding were suggested to contribute substantially to protein-aroma interactions. These findings provide molecular evidence for the binding of sweet-fragrant aroma compounds to salivary proteins and guidance for selecting aromas with suitable oral interaction properties for reduced-sugar foods.