REFRIGERATION OF FISH 



613 



800 pounds of fillets in an 8-hour clay, or 4,000 pounds in five such 

 batteries, one man being in attendance by rotation on the five batteries. 

 There is some loss of refrigeration in repeatedly warming and cooling 

 the apparatus, but this is not a large loss because of the low specific 

 heat of aluminum (about 0.20). 



The fillets are packed in temporary sheet-metal pans that hold 

 10 pounds each. From these pans the fillets are transferred to the 

 freezing receptacles. When the calcium brine is 10° below zero, 

 freezing is completed in about 50 minutes on cakes of the dimensions 

 mentioned. Lower temperatures and consequently more rapid 

 freezing is practicable, of course. 



Fig. 4G. 



-Cooke's method for individual fiilets. Frozen haddock fillets being taken 

 from freezer. Courtesy. Atlantic Coast Fisheries Co. 



INDIVIDUAL FILLETS 



Cooke also has designed a freezer of somewhat similar arrange- 

 ment for freezing individual fillets. The fillets are laid on aluminum 

 plates about 30 inches square and T Vinch thick. These plates 

 are placed on hollow shelves contained in an insulated cabinet. The 

 shelves are of cast aluminum with internal webbing that constitutes 

 a labyrinth through which the cold calcium-chloride brine circulates. 

 The webbing serves two purposes — namely, to distribute the cold 

 brine uniformly throughout the shelf for uniform freezing, and to 

 conduct the heat away from the surface of the shelf more rapidly 

 than it would be conducted by a smooth surface. The brine inlet 

 and outlet are attached to opposite edges of the shelf and are pro- 

 vided with double-throw valves, so that cold brine may be circulated 



