Production, bioactive properties, and potential applications of fish protein hydrolysates: Developments and challenges

The health benefits associated with consuming fish products are mainly attributed to their desirable nutrition profiles, including vitamins, minerals, essential amino acids, and polyunsaturated fatty acids. However, large quantities of fish proteins are presently underutilized or discarded as waste. Effective strategies to utilize fish proteins are therefore needed. Recently, researchers have focused on generating and characterizing bioactive fish protein hydrolysates and peptides and then studying their potential health benefits. The major methods of producing, separating, and purifying protein hydrolysates are initially given. Then, the biological activities and potential mechanisms of action of protein hydrolysates and peptides are discussed. Finally, current limitations and future possibilities of fish peptide identification, production, and bioactivity are identified and discussed. Fermentation, chemical synthesis, and enzymatic hydrolysis are effective methods of obtaining hydrolysates from underutilized fish protein by-products. These hydrolysates can then be purified by membrane separation and chromatographic methods to obtain bioactive peptides. The molecular characteristics of the peptides can then be identified using mass spectrometry. Fish hydrolysates/peptides have multiple biological activities, including antioxidative, lipid homeostasis modulation, anti-inflammatory, anticancer, neuroprotective, and antihypertensive activities, which make them promising nutraceutical ingredients for application in foods. Moreover, they often have emulsifying, foaming, and gelling properties, which means they may be suitable as multipurpose functional ingredients. Thus, waste-derived fish by-products may be turned into value-added functional ingredients designed to address chronic diseases. However, further research is required to develop large-scale commercially viable extraction and purification methods, develop robust structure-function relationships for peptides, and perform in vivo human studies of peptide bioactivity. •The production of protein hydrolysates from underutilized fish protein or by-products.•The purification and identification of bioactive peptides.•The main biological activities of fish hydrolysates/peptides.•Current food applications and future perspectives of fish protein hydrolysates/peptides.