with moisture-vapor-proof, heat-sealable overwraps is widely used. Some 

 cartons have covers with a cellophane window to display the contents of 

 the package but because of the high incidence of breakage the trend is 

 away from this type of package. 



Self -locking cartons are made in two general sizes, consumer 

 and institutional. The consimer sizes range from about 3 ounces to about 

 2-1/2 pounds. The more expensive products, such as shellfish meats, 

 are generally packaged in sizes from 3 to 12 ounces. Institutional packs 

 generally come in 5-> 7-1/2-, 10- and 20-pound sizes. 



Trays made of molded pulp are now widely used for prepackaged 

 meat products and, to a smaller extent, for some fishery products, such 

 as small fish, fish steaks, and fish sticks. One form of tray consists 

 of a sheet of paperboard with its four sides folded at right angles and 

 fastened together at the corners. Two trays may be used to form the top 

 and bottom of a complete teles cope -type box. The filled tray is over- 

 vrrapped with a transparent film which is heat-sealed. The trays are 

 sometimes lacquered to provide a high gloss. 



Metal cans have not been used to any extent to date in the 

 packaging of frozen foods. The need for a distinctive package to differ- 

 entiate the product from canned or heat-processed foods is probably 

 the principal reason for this. Tests recently conducted at the Seattle 

 laboratory of the United States Fish and Wildlife Service have shown 

 that fish frozen and stored in evacuated tin cans maintain their quality 

 much better than in other packaging materials. Changes in flavor and 

 color are almost eliminated. Among the advantages cited for packing 

 frozen fish in tin cans are (l) higher quality fish, (2) availability 

 in packaged frozen form of species not hitherto handled in the frozen 

 state, e.g. pink salmon, and (3) labor saving in preparation and pack- 

 aging through the use of high-speed can-handling equipment. Possible 

 disadvantages to this method of packaging frozen fish are (l) spoilage 

 hazards from improper storage, (2) difficulty of freezing round cans in 

 existing plate-type freezers, and (3) the usual mechanical fish-can 

 fillers cannot be used if the fish are processed in the form of fillets 

 or steaks. 



Another form of the metal package is a semi-rigid aliuninum 

 container or pan package. By using aluminum-pan packages producers of 

 prepared fish dinners can package their products so that the housewife 

 can prepare and serve the dinner without removing the fish from its 

 original container. A pan package is made of a sheet of heavy aliuninura 

 foil that is stamped or folded into a pan shape. The packages, made 

 in the form of trays, dishes, and plates, are generally tapered so 

 that they vrill nest for storage and are available with printed lids or 

 without lids if a transparent overwrap is to be used. VJhen used for 

 frozen foods they are generally placed in individual, rectangular car- 

 tons for added protection during distribution. 



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