Development of Quality Index Methods for Evaluation of Frozen Cod(Gadus morhua)and Cod Fillets

Two experiments were conducted to develop schemes for the rapid assessment of quality characteristics of frozen cod and cod fillets that could be used in industry to evaluate incoming material and for use in production planning and quality management. Three separate schemes for thawed whole cod, fillets and cooked fillets were developed using the quality index method. The schemes were tested using chemical and physical methods as comparisons. Principal component analysis of sensory, chemical and physical data showed an inverse correlation between water-holding capacity and the other variables (dry matter, formaldehyde concentration, total volatile nitrogen). The cod were grouped according to the length of time they had been frozen. The results of the quality index method for both whole cod and cod fillets loaded onto the same position in the PC plots indicated they were assessing similar underlying phenomena.