Prof. Stanley Gardiner and Prof. Nuttall, Fislt-freezing 185 



Fish-freeznuj. By Professor Stanley Gardiner and Professor 

 Nuttall. 



[Read 18 February 1918.] 



Fish-freezing commenced in 1888, in connection with Western 

 American sahnon. It was started to preserve the excess of fish 

 caught during the runs for canning in the shick season. The busi- 

 ness proved so profitable that fish began to be distributed all over 

 North America and exported to Europe, the chief market in the 

 latter being Germany. The fish are, as soon as possible after catch- 

 ing, brought to the refrigerator, frozen dry on trays at about 10° F., 

 this process taking about 36 hours. The fish then are drawn into 

 a room at 20" F., where they are dipped into fresh watei', their sur- 

 faces being thus covered with a glaze of ice. They are then packed in 

 parchment paper in strong wooden cases and exported to Europe 

 by refrigerator cars and cold storage steamers. The process is also 

 applied to halibut, haddock, cod, pollack and various flat fish in 

 America. It succeeds in preserving the fish for an indefinite period 

 of time, but the product breaks up in cooking, tending to become 

 rather woolly and loses flavour and aroma. 



To meet this a fresh process has now been developed, freezing 

 the fish in brine consisting of about 18 per cent, of salt at a tem- 

 perature of 5° to 20" F. The brine is an excellent conductor of 

 heat and cold. A large fish freezes thoroughly in three hours, a 

 herring in twenty minutes. After freezing, the fish returns to the 

 same condition as it was when placed into the brine; there is no 

 woolliness, no loss of flavour or aroma. The difference is due to the 

 fact that, whereas in dry freezing there is a breaking up of the 

 actual muscular fibres, due to the formation of ice crystals, in brine 

 freezing the ice crystals are so small that the muscular fibres are 

 entirely unaffected and on thawing return to the normal. In neither 

 form of freezing is there danger from moulds or putrefaction if the 

 fish is stored below 20^ F. 



The authors advocate the creation of a vast store of frozen her- 

 rings against time of scarcity, instead of the herrings being pickled 

 and exported. The value of fish as food is weight for weight about 

 the same as meat, containing the same constituents. If the excess 

 of the herring catch were stored in this way, there would be, on 

 pre-war figures, a store of herrings in this country to meet the 

 necessity for -albuminous food in the British Isles for at least eight 

 weeks. 



