552 



U. S. BUREAU OF FISHERIES 



protection is not used ; but at best it is expensive and troublesome to 



Gelatin in 3 or 4 per cent solution has been tried. This holds the 

 moisture even when the fish is defrosted, but is not impervious to 

 water or to gases soluble in water. While the gelatin film remains 

 on the fish water can diffuse through it slowly and evaporate. Tests 

 recently made with a gelatin glaze indicate that it offers no 

 advantages. 



BOXING, MARKING, AND WEIGHING 



Before frozen fish are placed in the cold-storage room they are 

 boxed or not, as the case may require. Boxes, as will be seen later, 

 afford a certain amount of protection to fish and make for more ex- 

 peditious handling. Breakage of fins, tails, and snouts is prevented, 

 and drying and rusting are not extensive. Boxes also provide an 

 easy means of marking weights, dates, names, and lot numbers. 

 Boxed fish also are more economical of space, for they make it pos- 

 sible to fill to the ceiling a room that otherwise could not be so filled 

 with assorted varieties and lots for which bins would have to be built. 

 Pan-frozen fish usually are boxed, especially in public freezers. 

 Large fish, such as halibut, salmon, carp, sturgeon, cero, king mack- 

 erel, red snapper, cod, and shad, which are frozen singly, often are 

 stored unboxed. The maximum economy of space is attained in 

 private freezers where pan-frozen fish are stored not boxed, the 

 rooms being filled entirely with the cakes, closely stacked. 



The boxes are made of any suitable wood — spruce, pine, fir, etc. 

 They are generally constructed as the " Style 4 " standard of the box 

 manufacturers. This style has the cleats on the ends of the boxes 

 and is preferred because, when the boxes are stored on end, the cleats 

 serve as battens to keep the boxes separated by spaces in which the 

 cold air can circulate. Salmon and halibut boxes to be used for 

 long-distance shipments usually are reinforced with a triangular 

 strip nailed in the corners. For packing cakes of pan-frozen fish 

 the boxes are made of a size just large enough to accommodate 4 or 6 

 cakes — that is, 100 to 150 pounds. Some inside dimensions of boxes 

 in use are as follows : 



Table 10 



The thickness of wood is %, ■&, or y 2 inch in the smaller boxes 

 and % or % inch in the larger ones. In public freezers, where each 

 lot of fish must be kept strictly intact, use is made of shallow extra, 

 or " ex " boxes. These are made to fit one, two, or three cakes of 



