Species identification of formed fishery products and high pressure-treated fish by electrophoresis: a collaborative study

The suitability and reliability of three electrophoretic methods of fish sp ecies identification, urea isoelectric focusing (IEF), sodium dodecyl sulfa te poly-acrylamide gel electrophoresis (SDS-PAGE) and native IEF, were eval uated on formed fish fillets and high pressure fish flesh by a collaborativ e study among four institutes. By following optimized standard operation pr ocedures, the protein patterns of processed fish were compared to patterns of raw reference samples. The method to use depended of the effect of proce ssing on the protein pattern. The proteins obtained from formed products we re not denatured and therefore any of the three methods proved to be adequa te, with a preference for native IEF which had a better discriminatory powe r for the species used. The high pressure process altered the proteins, and so only urea IEF and SDS-PAGE methods could be used. For these products, t he chosen method should then be the one with the better discriminating powe r for the species being examined. (C) 2000 Elsevier Science Ltd. All rights reserved.