RECOVERY OF PROTEINASES AND PROTEIN HYDROLYSATES FROM FISH VISCERA

This paper describes simple methods for diversified utilization of fish stomach and intestines for food, feed and biotechnological purposes. A high concentration of pepsin (9 g/litre) was obtained by ultrafiltration of the aqueous phase from a cod-stomach silage preserved with formic acid. A concentrate of trypsin-like enzymes could be obtained by ultrafiltration of fish sauce produced by salt fermentation of cod intestines. The permeate from the ultrafiltration contained the major part of proteinous material (peptides and amino acids), and had a palatable taste similar to traditional fish sauce. The results show that 7 litres of enzyme concentrate and 50 litres of fish sauce can be produced from 100 kg cod intestines within 16 days of fermentation at 27-degrees-C.