Nano-cellulose encapsulation for nutrient fortification in food powders: A narrative review

Cellulose, the most abundant polysaccharide in the world, plays a vital role in various industries, including food, pharmaceuticals, cosmetics, and textiles. Nanocellulose, which is nanoscale derivatives of cellulose, includes cellulose nanocrystals and cellulose nanofibers. While cellulose nanocrystals are not yet approved for food consumption, they have recently garnered significant interest in developing potential fortified foods due to their unique properties. This review highlights recent advances in the use of nanocellulose, including cellulose nanocrystals, cellulose nanofibers, and bacterial nanocelluloses as materials for encapsulation, with a particular focus on preparation methods. Thanks to their unique properties, nanocellulose stabilizes and encapsulates bioactive ingredients like oils, probiotics, enzymes, and flavors, enabling controlled release in the food industry. A popular encapsulation approach is Pickering emulsion, where cellulose nanocrystals can be used as a stabilizer, followed by a drying process, such as spray drying or freeze drying. This review uniquely focuses on powdered food-grade encapsulates, comparing drying methodologies and outlining current regulatory and translational challenges in advancing nanocellulose-based encapsulation toward practical food applications.