Pickering emulsion gels stabilized by protein and polysaccharide-based particles: A review of stability, synthesis,...

With a far longer stability than traditional emulsions, Pickering emulsion gels (PKEGs)-stabilized by solid particles-have proven highly efficient in a range of applications during recent years. Particles based on proteins or polysaccharides with distinctive amphiphilic structure are particularly well-suited for the production of PKEGs because of their natural occurrence, low cost, high nutritional content, and potential health advantages. Thus far, it has been shown that plant and animal proteins, as well as their complexes with polysaccharides, effectively stabilize PKEGs. The three main mechanisms that protein-based particles (Pr-Particles) stabilize PKEGs are the formation of a densely packed interfacial layer due to the irreversible adsorption of Pr-Particles, the accumulation of non-adsorbed Pr-Particles at the plateau borders or the formation of a gel-like network in the continuous phase, which decreases drainage, and depletion stabilization. In some applications, each type of Pr-Particles may provide exceptional advantages. This paper summarizes the main functions of PKEGs stabilized by proteins or polysaccharides, looks at the key mechanisms governing gel stability to better understand the complex behavior of PKEGs, and highlights the important scientific, technological advancements being deployed in the food industry using PKEGs. Some important applications of PKEGs in the food and nutraceutical fields are delivery of bioactive compounds, modulation of lipid digestion, fat substitution and design/formulation of novel products including 3D printed foods, which have been covered in the current study.