Abstract: Fish by-product is rich in protein and has high nutritional value, but its degree of comprehensive utilization is low, which causes a waste of resources, but also induces environmental problems. It has been shown that enzymatic hydrolysates of fish by-product mainly including small peptide hydrolysates could be used as potential food additives and nutritional supplements because of their functional properties such as antioxidant, antifreeze, antibacterial and antihypertensive activity. The aim of this article is to review the preparation, bioactive properties and applications of fish by-product protein hydrolysates and summarize the problems existing in the production of fish by-product protein hydrolysates and future trends, which could provide a reference for the research and application of fish by-product protein hydrolysates.

Key words: fish by-product; protein hydrolysates; bioactive properties