specifications for maximum sodium and fat 

 content must be met. Problems, for example, 

 in the penetration of excessive amounts of 

 salt during brine freezing of tuna may make 

 such a specification difficult to meet. 



Maintaining quality becomes a problem 

 in processing tuna at various stages of the 

 canning process. The problem of keeping 

 green tuna and other forms of rejects at 

 a suitably low level has to be met. During 

 the cooling of the precooked fish the fish 

 is susceptible to oxidation or other dete- 

 riorative changes. During the heat process- 

 ing and cooling of the cans, problems with 

 respect to scorch may develop. 



All these various types of quality 

 problems have made necessary the use of 

 careful quality control in the tuna in- 

 dustry. A few years ago it was unusual 

 to find a food technologist in any but the 

 largest tuna canneries. Today with mount- 

 ing problems and new specifications which 

 have to be met, even the smallest canneries 

 are introducing quality control into their 

 operations . 



Efficiency 



Another type of problem concerns the 

 efficiency of operation of the cannery, of 

 obtaining maximum yield from the fish, ef- 

 ficient utilization of manpower, and im- 

 provement in equipment to achieve greater 

 mechanization. Possibilities exist for 

 rather drastic alteration in operational 

 methods. For example, changes in storing 

 of tuna aboard the vessel might result in 

 unloading the frozen fish either without 

 any thawing or only partial thawing with 

 transfer for intermediate holding in a 

 cold storage warehouse for use as needed 

 in the cannery. 



Utilization of Byproducts 



Finally, we come to problems concern- 

 ing utilization of byproducts of the tuna 

 industry. Perhaps the most important of 

 these concern tuna meal and solubles on 

 the one hand and tuna oil on the other. 

 These byproducts are, of course, in compe- 

 tition with similar products produced not 

 only by other fisheries, but from other 

 sources as well. Since competitive prod- 

 ucts are constantly being improved, 

 parallel improvement in tuna byproducts 

 are required if their relative position 



in the markets is to be maintained. 



Fish meals, in general, are a premium 

 poultry feed which sell at prices somewhat 

 above competing protein sources such as 

 soybean meal. This is based upon the bet- 

 ter balance of amino acids in the fish 

 meals and the presence of other nutritional 

 factors including some of the known vita- 

 mins as well as unidentified growth factors. 

 Tuna meals, unlike most other fish meals, 

 are of highly variable quality because of 

 the practice of using different portions 

 of the cannery waste for meal manufacture 

 in different plants or at different times. 

 Thus diversion of dark meat (which formerly 

 all went into tuna meal) into pet food 

 production has altered, perhaps lowered, 

 the quality of tuna meal. Use in some in- 

 stances of visceral portions for a homo- 

 genized tuna product again diverts raw 

 material from tuna meal production and 

 alters quality. This variation in tuna 

 meal quality jeopardizes the premium 

 position which fish meals in general pos- 

 sess. It means that efforts along other 

 lines to maintain high quality and uni- 

 formity are needed. Similar considerations 

 also apply to tuna solubles production. 



Tuna oils likewise are not in the fore- 

 front of quality among fish oils. Condition 

 of raw material tends to produce a somewhat 

 lower quality oil for many purposes than 

 other fish oils. This is reflected in the 

 recent slow movement of tuna oil. One 

 solution to this problem would be develop- 

 ment of new uses for fish oils where the 

 qualities of existing tuna oil are not a 

 disadvantage. The other solution might be 

 improvement in processing to produce a 

 higher quality of oil. 



Diversion of tuna waste into animal 

 feed, particularly pet food has introduced 

 nutritional problems such as, for example, 

 the difficulties involving steatitis. A 

 considerable amount of research is needed 

 not only to solve this specific problem 

 but also to get a better understanding of 

 the problems involved in developing a 

 better balanced pet food. 



GOVERNMENT HELP IN SOLVING 

 PROCESSING PROBLEMS 



These, then, are some of the problems 

 of the tuna processing industry. Just 

 what is the Bureau doing to help the tuna 



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