Recently, a greater attention has been directed to a more effective exploitation of chitin, the second most available polysaccharide in crustacean's products. The shellfish processing industry produces unusable waste, thus posing a practical challenge. Approximately 75% of the total weight of crustaceans ends up as waste and there are actually no acceptable waste management solutions. Thus, the extraction of chitin from the shells of crustaceans, such as shrimps, crabs, prawns, lobster or krill, and its further use in the unprocessed or processed condition minimizes waste and produces valuable compounds. Chitosan, a deacetylated derivative of chitin, has many functional properties which can be used for various applications such as processing, preservation and food additives.