Enzymatic Hydrolysis of Sardine (<i>Sardina pilchardus</i>) By-products and Lipid Recovery

Abstract

Raw and cooked sardine by-products from the canning industry were used to prepare protein hydrolysates and oil using food-grade 0.5% commercial enzymes (Alcalase®, Neutrase®, and ProtamexTM) and a water/fish ratio of 1:1. The highest nitrogen solubilization and degree of hydrolysis were obtained with Alcalase and Protamex both with raw and cooked sardines, but raw by-products were more easily hydrolyzed by these enzymes than the cooked sardine. The peptide profile of the hydrolysates reflected the specificity of each enzyme. The highest percentage of oil released was obtained from raw sardine, and Alcalase and Protamex were the most efficient. The oil released had a dark color and high peroxide value.