Excellent quality fish protein concentrate can be prepared from a variety of raw materials. In this study, the use of whole cod, headed, eviscerated cod, cod trimmings, cod press cake and whole herring was studied as a source of raw material for the production of fish protein concentrate. The process previously described by Power for use with cod fillets was satisfactory for use with all material studied with the exception of herring. Final fat contents were between 0.018–0.056%. For use with herring a modification to the process was required to increase the efficiency of the second extraction. The second extraction, which used a 70:30 isopropanol + water mixture was changed to 99% isopropanol. With this modification a final fat content of 0.17% was achieved. The corrected Protein Efficiency Ratio values for all fish protein concentrates, with the exception of those produced from cod trimming press cake, were higher than that for casein. Lysine values, determined microbiologically were between 9.1 and 15.03% of the protein. The available lysine values were between 6.1 and 10.4% of the protein.
Problems in the development of fish protein concentrates
