Conversion of aquatic by-products into value-added food ingredients has gained great interest worldwide, and enzymatic hydrolysis is one of the most accepted methods for the recovery of by-product proteins. In our study, fins from silver carp (Hypophthalmichthys molitrix) were hydrolyzed by four enzymes (trypsin, alcalase, papain, and neutrase) and the antioxidant activity of the derived fin hydrolysates was evaluated both in vitro and in freeze-thawed bighead carp (Hypophthalmichthys nobilis) fillets. The results showed that fin hydrolysates by trypsin and alcalase exhibited strong in vitro scavenging activity against 2, 2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radicals and chelating activity to ferrous ions. Freeze-thaw-induced protein oxidation (the formation of carbonyls and disulfide bonds) and degradation (the loss of Ca²⁺-ATPase activity) were significantly (P < 0.05) inhibited by fin hydrolysates. In addition, fin hydrolysates reduced lipid oxidation as evidenced by decreased free fatty acid content, peroxide value, thiobarbituric acid reactive substances (TBARS), and fluorescent compounds after multiple freeze-thaw cycles. Therefore, fin hydrolysates by trypsin and alcalase could be potential natural antioxidants in preservation of fish fillets.

将水副产物转化为增值食品成分已引起全世界的广泛关注，并且酶促水解是回收副产物蛋白质最公认的方法之一。在我们的研究中，silver鱼（Hypophthalmichthys molitrix）的鳍被四种酶（胰蛋白酶，碱性蛋白酶，木瓜蛋白酶和中性酶）水解，并在体外和冻融的big鱼（Hypophthalmichthys）中评估了衍生的鳍水解物的抗氧化活性Nobilis）鱼片。结果显示，胰蛋白酶和alcalase的鳍片水解物在体外表现出强力对2，2'-叠氮基双（3-乙基苯并噻唑啉-6-磺酸）（ABTS）自由基的清除活性和对亚铁离子的螯合活性。 翅片水解物显着抑制了冻融诱导的蛋白质氧化（羰基和二硫键的形成）和降解（Ca ²⁺ -ATPase活性的损失）（P <0.05）。此外，翅片水解产物减少了脂质氧化，这通过多次冻融循环后游离脂肪酸含量，过氧化物值，硫代巴比妥酸反应性物质（TBARS）和荧光化合物的减少证明。因此，由胰蛋白酶和碱性蛋白酶水解的鳍片可能是鱼片保鲜中潜在的天然抗氧化剂。