Preparation and application of natural protein polymer-based Pickering emulsions

Abstract Emulsification is the effect of a liquid being uniformly dispersed as tiny droplets in another liquid that is immiscible. Traditional emulsification requires the addition of suitable surfactant to stabilize the emulsion. When the surfactant molecules are replaced by solid particles, the emulsion is known as Pickering emulsions (PEs). PEs with dispersed phase volume fraction above 74% are also named high internal phase Pickering emulsions (HIPPEs). The use of solid particles of natural origin allows PEs to be highly physically stable, environmentally compatible, and biodegradable compared to traditional emulsions. Among them, protein-based solid particles are well suited to stabilize PEs for their great emulsification properties and nutritional value. In this article, we reviewed the preparation of different forms of proteins and their emulsion stabilization properties and summarized the applications of protein-based PEs in various fields, including food, biomedicine, porous materials, biodegradable packaging films, sewage treatment, 3D printing, etc.