Protein value of cod and coalfish and some products for the young rat

The protein quality of cod muscle protein and of some products of cod and coalfish was determined in nitrogen balance experiments with young rats. In most of the experiments spray dried egg albumin was used as a standard of reference. All the fish proteins showed as expected a lower utilization than egg albumin, but the results indicated that the preparations tested had high biological values. There was no appreciable difference between raw cod fillets, acetone dried cod fillets, or acetone dried fillets which had been boiled before drying. Two pilot plant fish flours from cod fillet waste showed high biological values. There was no difference in the utilization values between freeze dried coalfish fillet pastes containing different amounts of residual bones. Stockfish flours showed utilization values of about the same magnitude as the acetone dried fillets. There was no difference in the utilization values for stockfish and paste made from stockfish soaked in NaOH or NaC03 («lutefisk»). A comparison between acetone dried cod and herring fillets and meat from porbeagle and basking shark showed the elasmobranchs to be less well utilized than the teleosts