170 DESCRIPTION OF IMPORTANT FISHERIES AND THEIR PRODUCTS 



Size grades of shrimp are expressed as ''count/' meaning the average 

 number of tails to the pound. Commercial size categories in common use 

 are shown below: 



Number of shrimp per 

 Classification pound {heads off) 



Extra jumbo Less than 15 



Jumbo 15 to 20 



Large 21 to 25 



Large-medium 26 to 30 



Medium 31 to 42 



Small 43 to 65 



Very small or bait 66 or more 



The price received for shrimp varies with the size, the largest shrimp 

 bringing the highest price. 



Refrigerated Brine. In some fisheries, especially in the Northwest, 

 refrigerated brine has been successfully used to replace ice as the cooling 

 agent for fresh fish on board vessels^^ Experiments in the southern 

 shrimp industry suggested that this might be a promising technique^- ^^ 

 Temperatures as low as possible above the freezing point of the brine 

 and the shrimp are desirable, these being about 29 to 32°F. Off-odors of 

 the shrimp held in this way can be combated by small concentrations 

 of aureomycin (five parts per thousand). Some early commercial trials 

 in the southern United States shrimp industry were discouraging and 

 the system was abandoned. Refrigerated brine is used by shrimp boats 

 in some other countries, including Panama and Colombia. In the Alaskan 

 shrimp industry, trials have been made involving the use of refrigerated 

 brine, but in the early 1960's this technique had not been perfected^'^-^'^^ 



Freezing at Sea. It is possible to freeze shrimp at sea as shown by 

 experiments by Dassow^ At present it appears not to be economically 

 feasible to carry out this processing on the vessels, however, due to the 

 extra costs associated with the freezing equipment and the skilled men 

 needed for such an operation. 



Processing 



Shrimp are marketed in several forms— fresh, frozen, breaded, canned, 

 cured, and as specialty products. In the past most shrimp were sold 

 fresh, but this restricted the market to areas close to the port of landing. 

 In recent years consumers have received shrimp mostly as frozen tails, 

 shell on. An increasing proportion of shrimp are being sold as frozen 

 breaded or as peeled and deveined shrimp. Canned shrimp now supply a 



