FISHERY INDUSTRIES OF THE UNITED STATES, 19 3 7 185 



fish meal but would also provide useful means in furthering study of 

 changes taking place during storage and the effectiveness of improved 

 storage practice. 



During the past year attention has been given to determining the 

 relative amounts of extractable material removed by different solvents 

 from fish meal soon after being prepared and after extended storage 

 under conditions known to lead to oxidative deterioration. Sixteen 

 solvents were tested on two separate types of fish meal. The most 

 significant aspect of the data secured on these tests illustrated the 

 widely differing effectiveness of individual solvents and the fact that 

 effectiveness is closely related to chemical structure. This will 

 materially facilitate the work contemplated during the ensuing year. 



In addition to the studies mentioned above, which were conducted 

 in the Seattle laboratory, the Bureau's nutrition laboratory at College 

 Park, Md., has been studying the physiological eft'ect of the develop- 

 ment of rancidity or oxidative deterioration in the fat of various fish 

 meals, and other chemical changes, in the feeding of both white rats 

 and baby chicks, as laboratory animals. This latter investigation 

 particularly emphasizes the effect on these animals of any physiological 

 and chemical changes which may be induced under varying conditions 

 of manufacture, handling, and storage, which may cause the develop- 

 ment of rancidity of the fat or the partial digestion of the protein in 

 these fish meals. These studies have not progressed to a point where 

 any conclusions can be reported. 



CHEMICAL PRESERVATION OF FISH AND FISH WASTE 



Several years ago the Bureau established a cooperative arrange- 

 ment with the Aquacide Co., Washington, D. C, for the conduct in 

 the Bureau's College Park technological laboratories of a study of 

 methods of chemical preservation of fish and fish waste. At many 

 points in the United States and in Alaska there are relatively small 

 accumulations of fish waste or waste fish, not sufficient to justify the 

 installation of machinery or mechanical equipment for the production 

 of byproducts, but sufficiently large to merit the development of 

 cheaper methods of utilization. The problem has been attacked 

 from two standpoints. One is the temporary chemical preservation 

 of the waste until it can be transported to some central point for more 

 complete mechanical reduction and the other is outright chemical 

 preservation or reduction for use as fertilizer stock, etc. 



As in 1935 and 1936, the Aquacide Co., during 1937, employed 

 and stationed in our laboratories Harold E. Crowther, R. H. Flowers 

 and C. E. Swift, research associates. Already, results of considerable 

 practical value have evolved from this program of cooperative research. 

 A chemical solution developed by the above company has been tested 

 on various types of fishery waste and has been shown to be very effec- 

 tive in its preservative qualities. In recent years its effectiveness 

 has been improved by numerous tests on fishery waste. One very 

 important commercial possibility, as a result of this work, is the 

 temporary chemical preservation of cod livers and other fish livers 

 at sea until these livers can be transported to a central plant for the 

 extraction of the oil. The widespread application of this method has 

 promise of saving from spoilage many fish livers which now do not 

 reach the plant quickly enough for the extraction of an oil of good 



