Abstract:The enzymatic hydrolysis process of antioxidant peptides from mackerel by-products was optimized and then the obtained antioxidant peptides were employed to prepare fish sausages. The minced mackerel meat was used as the raw material. Through single-factor experiments，the best protease was selected and its hydrolysis conditions were optimized. The formula of fish sausages was optimized through single-factor and orthogonal experiments. The results showed that the best protease was neutral protease，and the optimal hydrolysis conditions were neutral protease addition of 1 600 U/g，pH7，and 30 ℃. After purification with a 10 kDa ultrafiltration membrane，the peptide concentration of the hydrolysate increased from 840.14 μg/mL to 1 689.40 μg/mL.Moreover，the DPPH radical scavenging rate increased from 44.71% to 61.50%，and the reducing power increased from 0.38 to 0.55. Through orthogonal experiments，the formula of fish sausages （based on the mass of minced mackerel meat） was optimized as 20% water addition，40% corn starch addition，and 5.0% purified peptide powder addition. Compared with the control group without peptide addition，the addition of antioxidant peptides significantly increased the DPPH radical scavenging rate of mackerel sausages from 35.23% to 79.69% and the reducing power from 0.29 to 0.63. Furthermore，the content of crude protein also increased significantly.