Glycation of whey protein isolate and emulsions prepared by conjugates

Whey protein isolate (WPI) is widely used as emulsifiers for its good amphiphilic and nutritional value. In this study, the WPI-dextran conjugates were prepared via Maillard reaction to further improve functional properties of WPI. A294, browning degree and SDS-PAGE analysis verified the formation of macromolecular colored substances. FT-IR spectroscopy, CD spectroscopy and SEM confirmed that the grafting reaction destroyed intermolecular hydrogen bonds and affected the spatial structure of WPI. The grafting reaction mainly occurred between lysine, arginine and polysaccharides, which shielded the fluorescent group of proteins to a certain extent. The solubility and emulsibility of WPI were significantly improved after grafting reaction. Nanoemulsions stabilized by WPI-dextran conjugates demonstrated better stability at different pH, temperature, ion concentration, indicating that the glycosylation modification enhanced the electrostatic and spatial repulsion of WPI. Among them, electrostatic and hydrophobic interaction had a greater influence on the formation of nanoemulsions particles.