FISHERY INDUSTRIES OF THE UNITED STATES, 1935 85 



retarding the development of rancidity in other oil-bearing or fatty 

 foods, such as salted peanuts, potato chips, and others and it was 

 decided to determine whether they also would be effective in the 

 preservation of several fish, including Boston mackerel, Spanish 

 mackerel, haddock, and mullet. W. J. Hart, research associate for 

 the foundation, was stationed in our College Park technological 

 laboratory for conducting this work. Since the experimental work 

 was not begun until the last of the year, it is too early to report any 

 conclusive results. As described elsewhere in this report, Lyle 

 Anderson, another research associate for the foundation, was sta- 

 tioned in our Seattle technological laboratory to make similar tests 

 of these cereal products on fish livers, fish-liver oils, fish meals, and 

 other miscellaneous byproducts. 



CHEMISTRY OF FISH PROTEINS 



Because little is laiown regarding the chemistry of proteins in fish 

 and shellfish and because this information is badly needed to add to 

 the general knowledge of the food value of these products, a study of 

 this subject was undertaken during the past year. Accordingly, late 

 in 1935, determinations were started at our College Park laboratory 

 of the four nutritionally important amino acids in some of the commer- 

 cially important fish and shellfish. The amino acids being thus studied 

 are: Cystine, lysine, histidine, and tryptophane. At the same time, 

 digestibility and metabolism experiments with white rats were inau- 

 gurated in our nutrition laboratory at College Park to determine, or 

 to learn more about, the biological value of these proteins simultane- 

 ously with the study being conducted on the chemistry of such pro- 

 teins. Also, arrangements for cooperative research were made with 

 Western Maryland College, Westminster, Md., for participation in 

 that part of the program relative to the study of the chemistry of the 

 proteins. Miss Theima Chell was employed by the Bureau as a part- 

 time graduate student assistant to aid in this work, and the college 

 donated the services of three undergraduate student assistants as its 

 contribution to the cooperative study. In addition, the college pro- 

 vided, free of charge to the Bureau, laboratory facilities, equipment, 

 and chemicals, and the work is being conducted at Western Maryland 

 College under the supervision of Prof. Samuel B. Schofield, head of 

 the chemistry department. 



Considerable difficulty was encountered at first in the determina- 

 tions of the chemical constituents of the fish proteins as very littlt 

 worK has been done on this problem. It, therefore, became necessary 

 for our technologists to modify existing chemical methods or technique 

 (wliich have been worked out primarily for amino acid determinations 

 of agricultural foods) so as to make them more adaptable to fish. 

 The development of new technique also has been necessary to a cer- 

 tain extent. Therefore, progress on this project necessarily has been 

 slow. However, many determinations have been made of the four 

 above-mentioned amino acids in cod, haddock, mackerel, and Spanish 

 mackerel, but the work has not progressed yet to a point where defi- 

 nite results can be reported. However, there is reason to believe from 

 the data available, that the protein of fish will supplement the defi- 

 ciencies in other types of protein. 



