Abstract: Due to the excellent environmental-friendly, stability against coalescence and potential applications in the delivery of bioactive drugs of Pickering emulsions, great progress has been made in cosmetics, industry, food and other fields. Compared with traditional emulsions, Pickering emulsion does not contain any surfactants, and it is safe and stable. The application of inorganic particles and synthetic particles are also been greatly restricted when considering its toxicity and food safety issues. In terms of stable emulsion, the adsorption of Pickering particles at the interface is almost irreversible. Therefore, it is necessary to find more suitable food-grade particles as Pickering emulsion stabilizers. This article reviews the stability mechanism of Pickering emulsions, including particle wettability, three-phase contact angle, steric hindrance of particle formation. And this review also summarizes the latest developments in the production, characterization and stability of protein and protein-based Pickering particles stabilized Pickering emulsions in recent years, and point out its development direction. This article will lay a foundation for further expanding the application of protein nanoparticles in the food field.
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