Functionality developments of Pickering emulsion in food packaging: Principles, applications, and future perspectives

Food packaging is developed primarily for food safety and long shelf life. Advancements in material science and comprehensive encapsulation technologies provide numerous innovative packaging solutions for prolonging shelf-life and improving the quality and safety of food products. Among the conventional encapsulation methods, Pickering emulsions (PEs) as a stable alternative with food-grade colloidal particles have shown excellent performance in food packaging formulations. Recent advances in PEs have attracted wide attention because of their higher stability and and functionality. Using PE technology for the preparation of composite materials is a green and efficient method that has multiple uses in the food packaging field. PEs are stable emulsion systems that are stabilized by solid particles instead of surfactants. A PE has improved physical stability due to the solid particles irreversibly adsorbing on the oil-water interface and preventing droplets from aggregating. Food-grade particles have opened up new opportunities for PEs in the food packaging industry due to their use in food science. Currently, PEs systems are in high demand in food packaging materials, which is extremely important for practical applications in food products. This article describes the factors affecting the stability of PEs and summarizes the different physicochemical properties of PEs in food packaging. Additionally, available food-grade particles (polysaccharide-based and protein-based) developed as Pickering stabilizers are summarized. In any case, several studies have indicated that PEs are important systems for improving water vapor barrier properties of films, as well as for transporting hydrophobic components. This article provides insight into the use of PEs in food packaging and their potential applications (e.g., improving physicochemical properties, water vapor permeability barrier, mechanical properties and characteristics of material delivery systems). In particular, it was investigated how PEs affect the physicochemical properties and surfaces of intelligent/active films and the controlled release of bioactive compounds in these systems. Finally, the application of this system of PEs in intelligent/active and nanofibers packaging was evaluated on real food samples.