Construction of myofibrillar protein-based pickering emulsion for grass carp (Ctenopharyngodon idellus) based on interfacial self-assembly of spice aldehyde molecules: Mechanism and application of imine reaction-stabilized emulsion

The purpose of this research is to investigate multiple structural spice aldehydes (cinnamaldehyde (CA), citronellal (CN), and melonal (MA)) interact with myofibrillar protein in grass carp (GCMP) and the effects of interfacial interactions on stability properties of Pickering emulsion. It was demonstrated that the functional characteristics of interfacial protein might be greatly improved by the complexation of spice aldehydes with protein particles at the water-oil interface. The fluorescence quenching and molecular docking results revealed that the binding mode of spice aldehyde is primarily dominated by hydrophobic interactions, yet there are hydrogen bonding interactions exist in special structure. When comparing multiple structure aldehyde, CA has a greater binding affinity than CN and MA, as well as the most binding sites at different temperatures. Among them, the interaction of CA and GCMP is enhanced by forming hydrogen bonds through π-bonds owing to its special aromatic ring structure. The O/W structure was further stabilized by the formation of conjugated and unconjugated imines of interfacial protein with spice aldehydes. This work provides a theoretical basis for the interaction and development of protein particles with spice aldehyde in Pickering emulsion stabilization and novel ideas for the application of low value aquatic protein for high quality.