Species identification of cooked fish by disc electrophoresis

Abstract

The present objective methods of identifying fish species are based on the species-specific protein-separation patterns obtained on electrophoresis of the water-soluble sarcoplasmic proteins of fish muscle. As the proteins must be in their native undenatured state, electrophoretic identification of fish species has, so far, been restricted to raw fish.

An extension of the electrophoretic method to the identification of cooked fish is described. The protein fragments extractable in 6 M urea from the denatured proteins of cooked muscle can also be separated by electrophoresis into species' characteristic patterns that could be used for species identification. The separation patterns obtained on polyacrylamide gel for the urea extracts of cooked herring, halibut, plaice, salmon, cod and haddock are presented. In its present form the method does not apply to canned fish.