But by drawing heat from 

 products, moisture can be pulled out 

 too. The tiny water crystals frozen 

 inside the flesh of fish will evaporate, 

 leaving thousands of tiny spongelike 

 holes behind. When thawed, an 

 unprotected fish that has dehydrated 

 will be chewy, tough and possibly 

 rancid because the tiny holes allowed 

 oxygen to penetrate the fish and react 

 with fats and proteins. 



To prevent these problems, most 

 processors glaze their frozen products 

 with a thin layer of ice that will 

 evaporate without damaging the fish, 

 or they package the seafood, creating 

 a barrier that doesn't allow moisture 

 out or oxygen in. 



To lower the temperature on 

 seafood in a matter of minutes, 

 processors can use any number of 

 freezing methods. And they choose 

 their method based on the type of 

 product they are freezing. 



For freezing fillets and minced 



In short, 

 freezing is a 

 more efficient, 

 more economical 

 and now a more 

 quality-conscious way 

 to sell seafood. 



fish, most processors use plate or 

 drum freezers. For plate freezers, 

 refrigerants are pumped through 

 metal plates that are pressed directly 

 against a block of minced fish or a 5- 

 pound wax carton of fillets for a 

 quick freeze. In the case of drum 

 freezers, thin fillets or minced fish 

 are placed on the outside surface of a 



chilled, revolving drum and scraped 

 off when frozen. 



Blast freezers work as their name 

 suggests by freezing whole, large or 

 irregularly shaped fish with a super- 

 cold blast of air of about -40 F in an 

 insulated room. Fish are loaded and 

 unloaded in the freezing room for 

 each blast cycle. Air circulation is 

 critical, and dehydration can be a 

 problem. 



The spiral and tunnel freezers are 

 variations of the blast freezer that 

 eliminate dehydration problems 

 because products are frozen so 

 quickly. In the tunnel, fillets ride 

 along a continuously moving mesh 

 conveyer to be individually quick 

 frozen (IQF). 



In immersion freezers, processors 

 dip irregularly shaped seafood into a 

 very cold heavy brine. The immersed 

 fish or shellfish freeze rapidly 

 because heavily salted water doesn't 



Continued 



Buying and Thawing Vfozen Seafood 



When it comes to buying frozen 

 seafood, Joyce Taylor, Sea Grant's 

 seafood consumer agent, has the 

 following tips. 



If possible, look for signs of 

 freezer burn that usually appear as 

 light colored spots. Check for 

 rancidity by smelling the frozen 

 product and by looking for yellow 

 discoloration of fatty areas. 



Good quality frozen seafood 

 should have few ice crystals in the 

 package, and the grocer should have 

 it stored below the freezing line in 

 the freezer case. 



Read the frozen seafood package. 

 Check to see if the processor offers 

 information about how the product 

 was handled or frozen. Does the 

 processor suggest methods for 



thawing and preparation? Processors 

 who offer such information are 

 usually committed to a quality 

 product. 



Learn to identify brand names 

 and return to purchase those brands 

 that consistently deliver high quality 

 frozen seafood. 



To thaw seafood, place it in the 

 refrigerator. A 1 -pound package 

 will defrost overnight. 



For quicker thawing, place 

 seafood under cold running water. 

 Whole shellfish, such as shrimp or 

 clams, can be placed in a colander 

 with cold water running over them. 

 Place dressed seafood, such as fillets 

 or shucked shellfish, in a tightly 

 closed plastic bag, then immerse 

 them in a deep pan of cold water. 



Never thaw seafood at room 

 temperature or with hot or warm 

 water because you could encourage 

 the growth of harmful bacteria. 



When using your microwave to 

 thaw fish, defrost at about 30 percent 

 power. Follow the manufacturer's 

 instructions to determine defrosting 

 time (a pound of fillets defrosts in 

 about five to six minutes). 



Fish defrosted in the microwave 

 should be cooked immediately after 

 thawing. 



If you're buying previously 

 frozen fish or shellfish from your 

 grocer, Taylor advises consumers to 

 ask how long it has been since the 

 seafood was thawed, and as always, 

 use your nose to check for the odors 

 of spoilage. El 



COASTWATCH 17 



