Preparation and characterization of O/W emulsion stabilized by lysozyme and sugar beet pectin complexes formed by...

Food-grade protein-polysaccharide complex particles exhibit remarkable efficacy in stabilizing emulsions. In the present investigation, binary complexes of lysozyme (LY) and sugar beet pectin (SBP) were synthesized through electrostatic self-assembly and subsequently utilized for stabilizing emulsions. The self-assembly behavior and formation mechanisms of the LY-SBP binary complexes were investigated by systematically varying the charge and density through pH adjustments. The results indicated that the LY-SBP complexes exhibited the most robust electrostatic interactions at a pH of 6.2, leading to the formation of highly insoluble complexes with the smallest particle sizes (300.2 nm). These complexes demonstrated a superior capacity to reduce interfacial tension compared to LY alone. Fluorescence spectroscopy, Fourier-transform infrared spectroscopy, and microstructural analysis provided further insights into the complexation mechanism. The results suggested that hydrogen bonding interactions played a crucial role in the formation of LY-SBP complexes. Notably, the emulsion stabilized with 1.5 % LY-SBP showed better emulsification stability against freeze-thaw cycles, storage, and high ionic conditions, compared to emulsions stabilized with only LY. This improved salt tolerance renders LY-SBP emulsions more suitable for a variety of food processing applications.