The synergistic evolution of structural characteristics and interfacial behavior in the Maillard reaction process regulated the emulsifying properties of flaxseed globulin-flaxseed gum conjugates.

Abstract

Flaxseed globulin (FG), the predominant protein in flaxseed, exhibits suboptimal emulsifying properties that limit its food applications. The Maillard-driven glycation with polysaccharides offers a promising strategy to enhance protein functionality. This study elucidated the dynamic structural changes, interfacial behavior, and emulsifying properties of flaxseed globulin (FG)-flaxseed gum (FSG) conjugates. Covalent grafting between FG and FSG was confirmed by grafting degree and SDS-PAGE. The conjugates exhibited reduced particle size (206.33 ± 3.86 nm), increased absolute zeta potential (25.53 ± 0.43 mV) and enhanced solubility (76.48 ± 0.58%). Protein unfolding introduced greater disorder (random coils increased by 47.20%) and conformational flexibility (57.99%). Decreased interfacial tension accelerated protein adsorption and rearrangement at the interface, promoting a thicker, more stable interfacial layer. Notably, FG-FSG-6 h demonstrated superior emulsifying properties (76.37 ± 0.93 m2/g, 20.16 ± 0.49 min). This study established a foundation for engineering high-performance flaxseed globulin-based emulsifiers.