Industrial applications of crustacean by-products (chitin, chitosan, and chitooligosaccharides): A review

Food processing produces large quantities of by-products. Disposal of waste can lead to environmental and human health problems, yet often they can be turned into high value, useful products. For example, crustacean shell wastes from shrimp, crab, lobster, and krill contain large amounts of chitin, a polysaccharide that may be extracted after deproteinisation and demineralization of the exoskeletons. This review summarizes the current state of knowledge of these crustacean shellfish wastes and the various ways to use chitin. This biopolymer and its derivatives, such as chitosan, have many biological activities (e.g., anti-cancer, antioxidant, and immune-enhancing) and can be used in various applications (e.g., medical, cosmetic, food, and textile). Due to the huge waste produced each year by the shellfish processing industry and the absence of waste management which represent an environmental hazard, the extraction of chitin from crustaceans’ shells may be a solution to minimize the waste and to produce valuable compound which possess biological properties with application in many fields. As a food waste, it is important to also be aware of the non-food uses of these wastes.