REFRIGERATION OF FISH 611 



in New York in 1924. The apparatus is an insulated wooden 

 chamber, 4 feet square and about 7 feet high, with a side door. A 

 refrigerated coil was mounted in brine in the bottom of the cham- 

 ber. A pump draws the brine from the tank and forces it through 

 spray nozzles in the top of the tank. The fillets were packed in cir- 

 cular tin cans, 2 T 5 e inches deep and 12^4 inches in diameter, holding 

 10 pounds and provided with lid. These cans were suspended in iron 

 frames in the spray chamber and frozen, the temperature of the salt 

 brine ranging from 5° below zero to several degrees above. 



The fillets were stored and shipped in the cans. For shipping, the 

 cans were packed in insulated strawboard boxes. While the tins 

 afforded ideal protection against desiccation and rusting in storage, 

 they were unsatisfactory because they were expensive and because 

 of rust that developed during storage, which marred the external 

 appearance of the cans and discolored the fish. Some brine entered 

 the cans on which the lids did not fit perfectly. 



In order to overcome the difficulties just mentioned molds of cast 

 aluminum were made, 2 T % by 9 by 13 inches, with a flat lid fastened 

 on with two thumb nuts. These are suspended on an angle-iron 

 frame and conveyed into the brine-spray freezer. The frozen blocks 

 are wrapped in parchment and a craft paper (" Safepack"), two 

 sheets of which are cemented together by asphaltum, making it 

 waterproof. These wrapped blocks are stored in wooden boxes and 

 for shipment are put in paraffined cardboard boxes and packed in 

 the insulated corrugated box. Such boxes have been shipped success- 

 fully 1,500 miles in summer weather. In cold weather they usually 

 arrive at their destinations frozen. 



This method also is subject to objections. The aluminum boxes 

 are corroded somewhat by the salt brine (aluminum corrosion is 

 harmless, however), and the lids of the molds become warped by 

 repeated expansion of the fish in freezing, allowing brine to enter. 

 An improved type of can is of similar shape but made of galvanized 

 sheet iron, having an overlapping lid at one end, which is fastened 

 on. The can is suspended by the lid and brine can not enter. 



cooke's method 



A. H . Cooke, of The Atlantic Coast Fisheries Co. of New 

 York, devised a method of freezing, particularly for fillets to be 

 shipped after the manner of Birdseye, which is carried out in an 

 apparatus consisting of aluminum pans of double wall. 79 Calcium 

 chloride brine circulates between the walls equipped with temper- 

 ature-collecting webs. 80 Instead of a lid on each can the cans are 

 nested or stacked in such a way that the bottom of each can fur- 

 nishes the refrigeration for the top of the fish in the can below. 

 Two recesses are provided in each pan for two 10-pound blocks of 

 fillets. Five such double receptacles, one above the other, form a 

 battery that will freeze 100 pounds of fillets at a charge. 



Such receptacle pans have calcium-brine inlet and outlet pipes 

 on opposite sides of the middle of the pan, connecting by a swivel 



79 Patent pending. 



80 See Hesketh and Marcet, British Patent 6117 (1880), for first disclosure of this idea. 



