Nanochitin: An update review on advances in preparation methods and food applications

Chitin is an abundantly available polysaccharide and is the primary structural component of crustacean shells. Nanochitin can be made by extracting chitin from crustacean shell waste (CSW) by depolymerization and demineralization, then using various top-down and bottom-up approaches such as acid hydrolysis, ultrasonication, grinding, microwave irradiation, and electrospinning. Nanochitin finds wide application in the food industry due to its unique characteristics, including its small size, solubility, low density, high surface area, superior chemical reactivity, low toxicity, biodegradability, biocompatibility, antioxidant activity, antimicrobial properties, and excellent mechanical performance. In this paper, the recent advances in preparation methods of nanochitin from CSW are reviewed. Food applications such as nanochitin's ability to stabilize Pickering emulsions, as a reinforcing agent in food films, improving saltiness perception of food, inhibition of starch retrogradation, and lipid digestion are also discussed. This review will contribute to a deeper understanding of nanochitin's potential as a functional food ingredient.