A Review of Pickering Emulsions Stabilized with Cellulose and Bacterial Nanocellulose and Their Applications in Food Packaging

Pickering emulsions stabilized by solid particles have attracted the attention of many researchers in recent years, because they provide better stability than surfactants for emulsions. Bacterial cellulose is a combination of cellulose nanofibers produced by some bacteria, so bacterial cellulose is one of the bottom-up synthesis methods. The unique nanofibril structure of bacterial cellulose offers excellent physical and mechanical properties, including high porosity, modulus of elasticity, and high crystallinity. Also, among solid stabilizers, cellulose nanocrystals are used as good materials in the preparation of Pickering emulsions, which have desirable properties such as nanostructure, high aspect ratio, biocompatibility, biodegradability, amphiphilic, chemical stability, low toxicity, and renewable. This article is a review of the researches conducted in the preparation of Pickering emulsions stabilized by bacterial cellulose and cellulose nanocrystals. At first, a summary of the preparation methods of bacterial cellulose and bacterial cellulose nanocrystals is discussed. Then, an overview on the production of Pickering emulsions, preparation methods and parameters affecting their stability are given in detail. The results of this review show that various parameters such as the concentration of nanocellulose particles, their surface charge, the use of surfactants, the type and concentration of oil used, pH, emulsion preparation temperature, ionic strength, the method used for preparing nanocelluloses and Pickering emulsions together affect the overall stability of the system. Finally, a perspective of the applications of this type of emulsions in the field of food packaging is presented.