Mechanistic Insights into Time-Controlled Ozonation of Aquafaba: Implications for Oil – Water Interfacial Behavior in Complex Emulsions

Aquafaba has emerged as a promising plant-based ingredient capable of replacing egg functionalities in food systems; however, its interfacial and rheological stability in emulsions remains limited. This study investigated the mechanistic effects of controlled ozone exposure on the structural, physicochemical, and interfacial properties of chickpea aquafaba and their implications for emulsion stabilization. Aquafaba was exposed to gaseous ozone (9.03 mg.L−1) for 10, 20, 30, and 60 min, and the resulting structural modifications were evaluated through FTIR, surface hydrophobicity, sulfhydryl content, solubility, and zeta potential. Interfacial tension kinetics, rheological behavior, microstructure, and emulsion stability were also assessed. Ozonation promoted moderate oxidation of proteins, causing subtle conformational rearrangements without extensive denaturation. Intermediate exposure times (20–30 min) increased surface hydrophobicity, improved electrostatic repulsion, and enhanced interfacial adsorption dynamics, resulting in lower interfacial tension and higher interfacial pressure. These modifications produced emulsions with smaller and more uniformly distributed droplets, higher viscosity, stronger viscoelastic networks, and lower Turbiscan Stability Index values. Conversely, prolonged ozonation (60 min) induced excessive oxidation and partial protein aggregation, reducing interfacial flexibility and emulsion stability. Overall, controlled ozone treatment represents a promising non-thermal strategy to tailor aquafaba functionality and improve the performance of plant-based emulsions.