Ultrasound-assisted pH-shifting treatment: Effects on egg yolk protein interfacial adsorption and emulsification...

This study investigated the effects of ultrasound-assisted pH-shifting treatment on the emulsification and interfacial properties of egg yolk protein (EYP). The treatment increased the surface charge of EYP, enhancing electrostatic repulsion between protein molecules, which in turn promoted a 27.90 % increase in solubility and a reduction in average particle size (160.97 nm to 82.99 nm). The adsorption rate, interfacial pressure, and viscoelasticity of the egg yolk solution at the interface were significantly enhanced following the synergistic treatment (P < 0.05). Cream stability of the egg yolk emulsion improved by 95.13 %. The percentage of protein adsorbed at the interface and the interfacial protein concentration also increased significantly, contributing to emulsion stabilization. Furthermore, the synergistic treatment disrupted the structure of insoluble egg yolk granules, facilitating interfacial adsorption. These findings provided a theoretical basis for applying ultrasound-assisted pH-shifting to enhance the properties of egg yolk-based emulsified foods.