Sodium Bicarbonate-Assisted Cold Plasma Treatment of Wheat Gluten: A Synergistic Approach to Improved Functionality

This study explores the synergistic modification effects and underlying mechanisms of sodium bicarbonate (SB)-assisted cold plasma (CP) treatment on wheat gluten (WG). Compared with individual treatments, the combined treatment markedly improves the solubility, emulsifying properties, and foaming capacity of wheat gluten. Physicochemical and structural analyses show that CP treatment induces partial denaturation and surface etching of wheat gluten, while the introduction of SB mitigates excessive oxidation damage. It increases the accessibility of hydrophobic and sulfhydryl groups and facilitates the development of a more thermodynamically stable protein structure. Molecular dynamics simulations further reveal that under weak alkaline conditions, SB stabilizes local hydrophobic domains, reduces hydroxyl radical (·OH)-induced disordered unfolding, and maintains the protein in an extended, ordered state with high solvent accessibility. These findings provide a theoretical basis for developing efficient, green protein modification strategies in the food industry.