Possible use of waste products from the Salmon industry: Properties of Salmon gelatin

All rights reserved. Taking into account the global market, about 2.5 million tons of salmon could be caught or grown in 2014. A salmon skin is an important waste product from the salmon industry in Chile, with a typical skin representing about 5% of the fish, but ~75% of the whole waste from salmon. Therefore, it is an important natural source to use in the development of biodegradable products, such as collagen and gelatin. Gelatin is obtained from thermal denaturation of collagen under acidic or basic condition. One of the most important properties is its ability to form thermo reversible gels, however in recent years new applications have been discovered, in particular its capacity to form films. Edible coatings and films are added to cover fresh foods in order to extend their shelf-life, maintaining their organoleptic characteristics. Natural active compounds such as antioxidants and antimicrobial agents could be added to gelatin films. Salmon gelatin are different from other sources of gelatin (pig and bovine); it has lower gel strength due to differences on proline and hydroxiproline and molecular weight; however, it has antimicrobial activity which is attributed to amino groups-peptides in the gelatin extraction. The aim of the present review is to compile recent information about physical and antimicrobial properties of film forming suspensions and films based on salmon gelatin, and their possible applications.