Active biopolymer films from oil-in-water pickering emulsions for food preservation: a mini review

In response to societal demands, the food industry constantly seeks innovations for its products. Active food packaging, developed from biopolymers incorporated with Pickering emulsions, is certainly one of these innovations. New technologies are important for reducing losses and waste, maintaining quality, and increasing the availability of food for the growing world population. Packaging helps maintain moisture, prevent oxidation, and avoid food contamination by microorganisms or other impurities during transport and storage. Packaging produced with biodegradable polymers can contribute to environmental conservation and food preservation. The introduction of nanotechnology and the concept of active packaging into food science have expanded the functionality of materials. Added to biopolymer films, nanoparticles act as reinforcement and gas barriers. Bioactive substances, found in essential oils and plant extracts, impart antimicrobial and antioxidant properties to the films. In this field of food science, which encompasses many topics, this short review focused on presenting and discussing (i) the importance of adopting biopolymers as matrices for food packaging, (ii) the role of hydrophobic essential oils and extracts, rich in bioactive substances, when incorporated into biopolymer dispersions, and (iii) the formation and stabilization of active oil-in-water emulsions by the Pickering mechanism. Finally, (iv) the application of some emulsion films for the preservation of specific types of food is also reviewed.