Multi-spectroscopy and molecular simulation reveal the interaction of oleic glycerolipids modified wheat dough induced by thermomechanical treatment

In this study, the effects of heat combined with oleic acid and oleic glycerolipids on dough functionality were investigated. Mixolab results demonstrated that inhibition of dough retrogradation by exogenous lipids followed the order of oleic acid > monoolein ≈ diolein > rapeseed oil ≈ triolein. Multi-spectroscopic analyses indicated that thermomechanical treatment induced alterations in the inherent structure of proteins and starches, and promoted interactions between lipids and wheat proteins which led to static fluorescence quenching but did not drastically change their fluorescence lifetime. Moreover, compared with other doughs, the bound lipid content in dough containing oleic acid or monoolein was higher than that of free lipids, indicating they have strong binding capacity with the dough. Molecular docking simulations indicated that thermomechanical treatment induced strong interactions between lipids and starch in the dough. This study firstly provides a theoretical basis for elucidating the interaction between different oleic glycerolipids, starches and proteins.