Alternatives for adding value for the fish processing wastes

The fish farming industry, especially the marine extractive fishery, is an activity of great economic importance in many parts of Brazil. Industrial fish processing operations generate a significant amount of wastes, which are rich in proteins and long-chain fatty acids, among which the unsaturated omega-3 fatty acids are prominent. The aim of this study is to make a review about the technological alternatives available for the utilization of fish wastes, such as a way for adding value to this material, focusing on green technologies. This material can be processed to obtain oil, meal or silage, that may be applied in livestock feeding. The obtained oil can further be stabilized by means of interesterification reactions, considering that the structured triglycerides thus obtained can be used in animal feeding, with nutritional advantages over original oils. The fish wastes can be applied as a substrate for the production of texturized proteins, protein concentrate, mechanically deboned meat, surimi, reestructured products or even oil, used for human feeding. The conversion of the extracted oil into biodiesel is another proposal of particular interest in the field of alternative fuels.