No. 4 (192 1) BRINE-FREEZING 47 



The second type of the apparatus is designed to freeze large 

 (luantities of the same kind of fish, the cylinders containing the fish 

 entering and coming out of the brine automatically. It is needless 

 to describe it here. 



In operation, the tank is filled with brine made by dissolving 

 3 lb. salt in one gallon of water. For herrings this is cooled down 

 to some point a little below 10'' F. ( — ^I2'2°C.). With other and less 

 oily fish a lower temperature is required, for salt penetration depends 

 upon two factors, the oily or non-oily character of the fish and the 

 degree of temperature. The lower the temperature the less 

 danger is there of salt penetration, similarly oily fish resist penetra- 

 tion much better than white-fleshed non-oily fish ; for plaice the 

 temperature should be as low as 0^ F. ( - lyS'^ C). 



When the temperature has been reduced sufficiently, the cylind- 

 er is loaded with fish to about five-eighths of its capacity, and 

 then lowered into the tank so that its spindle rests in the bearings 

 provided. On ope end of the spindle is a cogged wheel which 

 engages an endless chain; this when set in motion turns the 

 cylinder slowly ; this rotation aided by the baffle plates keeps the 

 fish in constant motion and so prevents them from adhering to 

 one another and also from massing together and so taking a longer 

 time to freeze completely. 



The OttcscH inetliod Rs developed in commercial practice is most 

 practical. It is, however, in my opinion, inferior to the Billingsgate 

 method in certain ways— («) it has not such a perfect arrangement 

 for keeping the fish in constant motion, though I admit that in 

 working practice the movement obtained appears to be adequate, 

 and (/?) it entails more handling of the fish, for the freezing recep- 

 tacles being smaller the operations are less automatic in operation. 

 On the other hand it appears slightly simpler in design. 



The Ottesen process has the merit of being in actual commer- 

 cial use. A wealthy Danish corporation has acquired the Ottesen 

 patents and has established large and well-equipped brine-freezing 

 works and cold-stores at Esbjerg and Skagen in Denmark, at 

 Gothenburg in Sweden, the North Cape in Norway, and Abo in 

 Finland. The parent company, the Danske Frysnings Company, 

 has a capital of Kr. 8,000,000. 



The capacity of these factories is as follows : — 



Esbjerg, a daily output of 30 tons of frozen fish and cold storage 

 capacity for 550 tons. 



