Invited review: Unraveling whey protein-flavor interaction mechanisms-Advances in instrumental, computational, and sensory approaches.

Whey protein is part of a multibillion-dollar industry driven by rising consumer demand; however, its broader use is limited by its high reactivity with flavorings and potential for off-note development. Therefore, understanding the mechanisms underlying whey protein-flavor interactions is crucial. Although whey proteins can influence multiple aspects of flavor, their greatest impact is on volatile aroma. Whey protein-volatile interactions primarily occur through hydrophobic interactions, in addition to hydrogen bonding, electrostatic interactions, and Van der Waals forces. Volatiles with reactive functional groups may also engage in covalent activities, including Michael addition, Schiff base formation, and disulfide bonds, which are of utmost importance due to their irreversible nature and effect on flavor stability and release. Nevertheless, data on these interactions is lacking, and limited literature has covered the key protein components within whey protein. Numerous instrumental, computational, and sensory tools have been applied to elucidate protein-volatile interactions, yet each technique presents distinct advantages and limitations. In addition, a combination of methods is essential to comprehensively characterize whey protein-flavor interactions, though the integrated approaches are rarely employed. This review summarizes the mechanisms of whey protein-flavor interactions, highlighting key gaps in current research. It also discusses instrumental, computational, and sensory methods, guiding future research toward an integrated analytical approach.