Table of Contents
MINISTRY OF AGRICULTURE, FISHERIES AND FOOD
TORRY RESEARCH STATION
TORRY ADVISORY NOTE No. 27 (revised)
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Describes the spoilage of fish and sets out the general principles for freezing fish for the purpose of retarding spoilage by preparation for frozen storage. Describes what happens when fish flesh is frozen, defines quick freezing and the problems associated with slow freezing. Recommends freezing the thermal centre to at least -20°C so that the average temperature of the product entering the cold store is at or below -30°C. Advises on selection and handling of the raw material before freezing to make a good frozen product, the correct use of different types of freezer, air-blast, plate and spray freezers, on glazing, and on the consequences of delays in storing the frozen product at -30°C. In addition to the other Notes referenced in the text, this Note is relevant to many Notes in the series in which freezing of a product or whole fish is discussed, e.g. Notes 34 and 75. This Note should also be read in conjunction with Note 28 which deals with cold storage of frozen fish.
(FAO in partnership with Support unit for International Fisheries and Aquatic Research, SIFAR, 2001).
The purpose of freezing
What happens during freezing
How to make a good product