For fishermen with larger boats and the required capital for 

 a freezer installation the solution of the quality problem has been the 

 freezing and packaging of raw headless shrimp aboard vessel. Other 

 methods successfully applied for the purpose of preserving quality are 

 the holding of fresh shrimp aboard vessel in refrigerated sea water or 

 the provisional freezing of shrimp at sea in low-teaaperature brine 

 followed by thawing, packaging, and refreezing ashore. 



Technologists of the United States Bureau of CoBmercial 

 Fisheries are inclined to favor the freezing of shrimp in brine as a 

 method of quality preservation. The primary advantage of this method 

 is to reduce the spoilage which results from allowing shrimp to remain 

 out of water too long before processing. Other advantages lie in the 

 reduction of storage space required aboard vessels since ice does not 

 have to be carried; shrinrp frozen in this manner are individually glazed 

 so that any amount may be removed and thawed without damage to the 

 remainder. The method so far has failed to gain full acceptance by 

 the Industry because of certain attendant disadvantages. Primary among 

 the latter is the high cost of the installation required (see Chapter 

 II - Agents of Production). Also, crews must be trained in the opera- 

 tion and maintenance of the refrigeration equipnent. 



Experiments have indicated that shrimp held in sea water 

 chilled to 29-32° F. are superior in flavor and appearance to shrinrp 

 held in crushed ice. "Black- spotting" is eliminated. A weakness of 

 the method is the development of undesirable odors in the shrimp. 



Results of additional tests conducted by the University of 

 Miami, Florida (see above), further proved that: (a) concentrations 

 of 5 to 10 p. p. m, aureomycin hydrochloride eliminated the undesir- 

 able odors of shrine* , (b) no measurable differences in quality coaild 

 be detected among shrimp held in three sizes of ice particles, (c) 

 shrimp dipped twice for 1 minute periods in 2-1/2 percent concen- 

 trations of sodium bisulfite showed marked reduction in the amount of 

 melanosis or "black-spot" after being held on ice. 



In Canning Establishments 



In the processing segment of the industry quality control is 

 most advanced in canning establishments. Tixe canners adhere to to 

 established set of standards. In most instances, these standards are 

 based on those developed either by the National Canners Association or 

 by the United States Food and Drug Administration. The plants fre- 

 quently hire the service of consulting food technologists who together 

 with regular plant personnel peurtidpate in the inspection of the 

 product. 



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