Applications of Seafood By-products in the Food Industry and Human Nutrition

The seafood processing industry generates more than 60 % as by-products, which include bycatch and other secondary products derived from a manufacturing process, such as heads, gills, skin, trimmings, fins, frames, bones, viscera, blood, and roes of commercial fish species. These by-products can be transformed into valuable products, such as fish oils, fish enzymes, gelatin, collagen, carotenoids, chitin, chitosan, glucosamine, functional foods, nutraceuticals, antifreeze compounds, surimi, fish protein hydrolysates, fish protein concentrates, and fermented fish products; hence, they can be utilized in the food industry and for human nutrition. Fish oil, which has numerous health benefits, can be used to impart a functional property to food products. Fish enzymes are a natural food-grade substitute for chemicals that are used to hydrolyze or denaturate proteins. Chitin, chitosan, and their oligosaccharides are applied as antioxidants, antibacterial and antifungal agents, and functional compounds in food industry. Gelatin is used for the purposes of gelling, edible coating, emulsification, and microencapsulation. Fish protein hydrolysate and concentrate, which pose many functional properties, have the potential to be used as a protein supplement or for protein fortification in foods. Antifreeze compounds have a vast spectrum of applications in frozen food technology and in the manufacturing of low-fat foods. Fish mince and fish surimi are cheap meat analogues that can substitute expensive meat varieties. Advanced techniques are being used and there is the need for further research to simplify and optimize the extraction procedures and to overcome the constraints that limit the application of these by-products in the food industry and for human nutrition.