Effect of Stage of Rigor and of Freezing–Thawing Processes On Storage Quality of Refrozen Cod
- 1 February 1968
- journal article
- research article
- Published by Canadian Science Publishing in Journal of the Fisheries Research Board of Canada
- Vol. 25 (2) , 299-320
- https://doi.org/10.1139/f68-025
Abstract
Trawler-caught cod were frozen before and after rigor mortis in brine (23% NaCI) and between refrigerated plates, thawed in circulating water at 7 C or in a conveyorized microwave oven, then processed into fillets which were packaged, plate-frozen, and stored at −18 C.All samples thawed satisfactorily in circulating water. Some overheating was encountered during thawing in microwaves. But the equipment was not developed sufficiently to permit assessment of the commercial potential of microwave thawing.Examinations of the fillets from the thawed fish for appearance, odor, and texture showed that freezing pre-rigor is preferable to freezing post-rigor and that thawing by means of microwaves is preferable to thawing by means of water. Freezing or thawing methods did not affect the pH of the thawed fillets.Results of organoleptic and chemical tests to determine the changes in quality of the refrozen fillets packaged and stored at −18 C for 12 months indicated that neither the average taste panel scores nor the chemical tests for moisture, total lipid, free fatty acids, and extractable protein nitrogen showed any difference attributable to state of rigor, freezing method, or thawing method. The taste panel slightly preferred the texture of fillets from fish frozen pre-rigor and from fish frozen in brine. Free fatty acids increased sharply as a result of thawing and refreezing, and the rapid increase continued during the first 2 months of frozen storage. Taste panel scores correlated significantly with free fatty acids (1% level) and with extractable protein (5% level).This publication has 9 references indexed in Scilit:
- Frozen fish muscle—Chemical changes and organoleptic qualityCryobiology, 1967
- Effects of Water and Dielectric Thawing Processes on Shelf Life of Double-Frozen Cod and RedfishJournal of the Fisheries Research Board of Canada, 1967
- Studies on the Quality of Newfoundland Cod. 10. Effect of Some Commercial Freezing Rates on the Frozen and Stored Quality of Trap CodJournal of the Fisheries Research Board of Canada, 1965
- Temperatures and Thaw-Drip Associated with Electronic Thawing of Newfoundland CodJournal of the Fisheries Research Board of Canada, 1964
- Phospholipid hydrolysis in cod flesh stored at various temperaturesJournal of the Science of Food and Agriculture, 1960
- A RAPID METHOD OF TOTAL LIPID EXTRACTION AND PURIFICATIONCanadian Journal of Biochemistry and Physiology, 1959
- Further Study of the Influence of Short Storage Periods, 3 Days to 2 Weeks at 15°F., on the Quality of Frozen Cod Stored at 0°F.Journal of the Fisheries Research Board of Canada, 1957
- Yellow Discoloration and Deterioration in Frozen Lobster MeatJournal of the Fisheries Research Board of Canada, 1957
- Simplified Statistics for Small Numbers of ObservationsAnalytical Chemistry, 1951