Solubilization of Fish Scrap by Enzyme Treatment

Abstract

Fish scrap usually comprises about one half of the carcass of raw material fish for processed food. The purpose of a series of studies is to establish recovery methods of proteinaceous materials from the fish scrap by enzymatic digestion and to convert them into useful byproducts such as fish sauces. In this paper, digestion of offal of croaker and horse mackerel by commercial enzymes and composition of scrap of raw materials for Kamaboko and Fish sausage were investigated. Activities and optimum pH of the enzyme examined were as follows. A-P was found to have enzyme activity of 7, 000 F.U. at optimum pH 7, B-SP 20, 000 F.U. (optimum pH 8 and near 11), C-AF 30, 000 F.U. (optimum pH 8), D-M 15, 000 F.U. (optimum pH 5), and E-T 6, 000 F.U. (optimum pH 5) respectively. More than 10% of salt cocentration was necessary to exert preservative effects during enzyme digestion of raw scarp of croaker and horse mackerel. When the enzymes were applied to raw and cooked scrap of croaker and horse mackerel, C-AF showed the highest degree of digestion followed by A-P and B-SP in descending order. D-M and E-T showed the lowest degree of digestion. Cooked fish scrap was less digestable than raw scrap by the enzymes.