Nanocelluloses review: Preparation, biological properties, safety, and applications in the food field

Functional diet and food safety requirements, as well as reducing the consumption of nonrenewable resources and environmental pollution are the important development themes on food processing. The development and application of edible nanocelluloses (NCs) is an urgent need in the current food field. NCs are divided into three types, including cellulose nanofibrils, and cellulose nanocrystals from natural fibers, as well as bacterial cellulose synthesized by bacteria. In this review, recent developments in surface modification, biological properties, safety issues, and their applications in the food industry were highlighted. NCs have application limits due to native hydrophilicity, surface modification strengthens their hydrophobicity and stability in the oil phase. NCs exhibit excellent physicochemical properties and successfully be used as edible coatings, emulsion stabilizers, and functional food ingredients. In particular, NCs and modified NCs can be used as low-calorie fat substitutes and prebiotics for improving gut microbiota. However, the biological properties and safety assessments still require more attention, as well as establishing the regulations for food applications.