Effects of α,β-unsaturated aldehydes on the structural, oxidative, and digestive properties of oyster myofibrillar...

This study investigated the effects of ten structurally diverse α,β-unsaturated aldehydes on structural, oxidative, and digestive properties of oyster myofibrillar proteins (MP) during thermal processing. Results showed that aldehyde treatment induced conformational alterations of MP, promoted protein oxidation, and caused amino acid loss. In vitro digestion assays further showed that aldehyde-modified MP exhibited reduced digestibility, lower hydrolysis degree, and altered molecular weight distribution. Among them, acrolein exerted the strongest oxidative and digestive impacts, increasing carbonyl content by 1.69-fold and reducing digestibility by 46.25 %. Mechanistic analysis indicated that aldehyde-induced oxidative crosslinking and aggregation reduced protease accessibility and hydrolysis efficiency. Moreover, in monoenal series (C3-C10), oxidative aggregation displayed a decreasing-then-increasing trend with chain length, while conjugated dienals generally caused greater oxidative damage and digestibility loss than monoenals. These findings reveal the structure-activity relationships of α,β-unsaturated aldehydes and their detrimental impacts on seafood protein quality and nutritional value, with implications for processing strategies.