Exploring molecular mechanism of fish myofibrillar protein adsorbing and releasing aldehydes with different structures

Expounding the interaction effect between myofibrillar proteins (MPs) and odorants for directional regulation of fish flavor is necessary. Interactive relationship between MPs and six aldehydes contributed to fish aroma with different chain lengths and saturations were investigated via multiple spectroscopy and molecular docking. Aldehydes binding capabilities to fish MPs in the order: Decanal> Hexanal> (E)-2-Decenal> (E)-2-Nonenal> (E,E)-2,4-Decadienal> (E,E)-2,4-Heptandienal. Each mole of MPs can bind about 2660 mol Dec while as to HDE just about 1000 mol due to the effect of chain length and saturation. The change of hydrophobic cavity in MPs contributed to the difference in aldehyde-binding capacity. Tryptophan and tyrosine residues of MPs mediated changes in the hydrophobic microenvironment. Besides, hydrogen bonding and Van der Waals forces were the main force dominated the interaction. Further, it described the molecular mechanism about MPs and aldehydes interaction and proposed a method to disrupting the interactions between MP and fishy odor compounds to help fish product aroma control.