Influence mechanisms of particle concentration and oil content on the formation and stability of rice bran protein-based Pickering emulsion

This study is dedicated to fabricating rice bran protein particles (RBPPs) through a thermal-acid modification strategy and exploring their potential as Pickering emulsifiers. The results confirmed that compared with rice bran protein (RBP), RBPPs exhibited enhanced hydrophobicity, reduced interfacial tension, and favorable wettability (83.4 ± 5.2°). Subsequently, Pickering emulsions were constructed using RBPPs as emulsifiers, and the effects of RBPPs concentration and oil phase fraction on the structure and performance of the emulsions were investigated. The results indicated that increasing the RBPPs concentration or oil phase fraction could enhance the stability and viscoelasticity of Pickering emulsions. Confocal laser scanning microscopy (CLSM) and interfacial protein content results demonstrated that at 4.0 wt% RBPPs concentration or 75 % oil phase fraction, the emulsions exhibited the highest interfacial protein content and formed a tight interfacial film, thereby endowing it with excellent storage stability, centrifugal stability, and the ability to protect lipids. Additionally, adjusting the pH value could effectively regulate the structure and performance of the emulsions. This research is of great significance for the development of new Pickering emulsifiers and the preparation of Pickering emulsions with adjustable structure and performance.