David Green 



Sam Thomas 



freeze until well below the freezing 

 point for pure water. 



For the fastest freeze possible, 

 processors turn to cryogenic technol- 

 ogy. This more expensive freezing 

 method uses ultracold liquid nitrogen 

 or carbon dioxide to drop the temp- 

 erature on fish and shellfish in a 

 matter of seconds. 



The product passes along a 

 conveyor belt through a cryogenic 

 tunnel where liquid nitrogen or 

 carbon dioxide is sprayed. As the 

 liquid vaporizes in the air, it picks up 

 heat from the product, leaving behind 

 one of the best frozen products you 

 can find, says Sam Thomas of 

 CryoTech Industries Inc. 



Just outside of Aurora, Thomas 

 runs CryoTech, which specializes in 

 cryogenically freezing Atlantic blue 

 crab — whole and in half-clusters. 

 Blue crabs enter his plant alive and 

 kicking and pass down a series of 

 conveyers belts to be cleaned, 

 cooked, frozen to a frosty tempera- 

 ture of -20 F, glazed, packed and 

 stored in the holding freezer in less 

 than one hour. 



Thomas says he chose cryogenic 

 freezing to ensure a consistent supply 

 of top quality frozen crab. He 



supplies his frozen crab clusters to a 

 restaurant chain that sells the frozen 

 crustaceans year-round to throngs of 

 hungry customers. 



When it comes to freezing blue 

 crabs and crab meat, Thomas says 

 cryogenic freezing does the best job 



Inside the freezer, 

 frozen fish and shellfish 

 can come up against 

 another problem: 



freezer burn 

 or dehydration. 

 Processors commonly 

 prevent this problem 

 by water glazing or 

 using a moisture-barrier 

 film or vacuum pouch. 



of retaining a freshlike texture, 

 moisture and good flavor. The 

 process is more expensive than 

 other freezing methods, but the 

 crab's irregular shape and the texture 

 of its meat make cryogenics a better, 

 more quality-conscious freezing 

 alternative. 



In fact, the crab meat is in such 

 good shape that Green has been 

 working with Thomas to see if the 

 meat from previously frozen crabs 

 can be picked and packed for the 

 crab meat market. In a project funded 

 by the National Coastal Resources 

 Research and Development Institute, 

 Green has been evaluating the 

 quality, yields and safety of cryo- 

 genically frozen meat. 



Thomas says cryogenic freezing 

 isn't for every seafood product. 

 Some products freeze just as well 

 using the less expensive mechanical 

 methods. 



But no matter what method you 

 use, Thomas says to ensure a good 

 quality frozen product, freezing 

 should be the goal of the processor 

 from the beginning. 



"Freezing shouldn't be used as a 

 backup plan for seafood that can't be 

 distributed fresh because of seasonal 



1 8 MARCH! APRIL 1993 



