6 BULLETIN 635, U. S. DEPARTMENT OF AGRICULTURE. 



so that he can take readings of the air at various heights, especially 

 at and above the upper fish. Every operator, of course, under- 

 stands the importance of keeping doors to cold storages closed, par- 

 ticularly when they open into outside air or into halls warmer than 

 the storage rooms themselves. 



PACKING FISH FOR STORaGB. 



Before storage, frozen fish, especially on the Atlantic coast, com- 

 monly are placed in boxes lined with heavy Manila paper, which 

 makes a better-looking package and gives additional protection. 

 These boxes simplify the handling and shipping of fish, and also 

 enable warehousemen to comply with any local laws which require 

 that the date of entering the storage be stamped on the packages. 

 Boxing the frozen fish before storage, by lessening the free circula- 

 tion of air among the fish, helps also to prevent evaporation of the 

 ice glaze, for ice evaporates even at freezing temperatures, as is 

 evidenced by the gradual shrinking of a block of ice outdoors, even 

 in zero weather. Boxed fish which have received from three to five 

 glazings usually keep from three to five months without losing their 

 glaze, or much longer than unboxed fish exposed to the air. 



Four or five cakes of the panned fish, or 120 to 160 pounds, com- 

 monly are packed in one box, whose length and width are just large 

 enough to take these cakes from the pans. Separately frozen fish, 

 such as halibut, salmon, and other large fish, generally are first 

 wrapped in a fish-wrapping paper, usually a vegetable parchment 

 paper, and packed carefully in boxes lined with Manila paper. On 

 the Pacific coast longer narrow boxes are used for packing halibut 

 and salmon. While under some conditions the cheaper sorts of fish 

 are stored in bulk, either in bins or in stacks, the boxed fish keep their 

 glaze better and are less liable to damage from handling. 



REGLAZING. 



Because the glaze gradually evaporates, it is necessary, if the fish 

 are to be kept in storage for a long time, to remove them from their 

 boxes and reglaze them at intervals of from three to four months. 

 Reglazing of fish stacked or kept in bins is somewhat more difficult. 

 A method occasionally followed in reglazing such fish is to use a 

 hose with a special spray nozzle, similar to that employed in white- 

 washing. The nozzle plays a finely-divided stream of clean water 

 on the piles of frozen fish, and this, freezing rapidly, reglazes them 

 more or less satisfactorily. The glaze naturally evaporates most 

 rapidly from the outer surface of the pile most exposed to air, and 

 these parts fortunately are most accessible to the reglazing spray. 



