Fish waste to fish meal: potential, sustainability and emerging issues related to micro plastics and regulations

Abstract

Massive growth in global fisheries and aquaculture production driven by the development of fishing technologies and exerted by the world population pressure has resulted in a remarkable increase in fish waste. The annual average discard amount was estimated to be 7.3 million t for the period from 2016 to 2020. The discard from marine capture commercial fisheries globally is a major concern in terms of environmental sustainability and cost of disposal. Production of fish meal is considered a practicable solution for the utilization of these wastes in a sustainable manner with a significant economic return due to the increasing demand from aquaculture and livestock industries, and occasionally for the utilization as a high-quality organic fertilizer. Fish meal is enriched with a protein source and could be utilized as a feed ingredient due to its excellent amino acid profile, excellent digestibility, high palatability, lack of anti-nutritional factors, and large acceptance by farmers. Due to climate change, habitat degradation and overfishing, wild fish catches used for fish meal are in decline, thus necessitating the increased utilization of fish waste to produce fish meal. However, the inclusion of microplastics in the fish meal and legal and regulatory issues, i.e., intra-species mixing, contamination with endangered fish species, and illegal, unreported, and unregulated fishing, need to be taken into account while utilizing the fish waste to produce fish meal. The review suggests that the utilization of fish waste for fish meal is vital for the future expansion of the fish meal industry, and also for the subsequent expansion of aquaculture and livestock industries in a sustainable manner while driving a circular economy and ensuring environmental sustainability.