108 U. S. BUREAU OF FISHERIES 



The scope of the studies being made on the manufacture of this 

 product include the development of a method of manufacture where- 

 by: (1) The original nutritional value will be altered as little as pos- 

 sible, (2) the resultant product will stand up in color and taste during 

 storage, and (3) the flour will lend itself to satisfactory inclusion in 

 food recipes. Preliminary data indicate that these requisites can be 

 realized more closely by an extremely rapid removal of moisture at 

 relatively low temperatures. 



The work accomplished during the latter part of the past year has 

 consisted in the design and construction of an apparatus which will 

 disperse the fish material in a drying medium in such a manner that 

 •extremely rapid drying can be effected. Preliminary studies on the 

 nutritional value of this material have shown that different portions 

 of the waste are more nutritious than others. 



HADDOCK-LIVER OIL 



■ The increasing catch of haddock in the New England ground-fish 

 fishery has made it imperative that more be known concerning the 

 chemical nature and biological value of haddock-liver oil. This is 

 especially true since it is believed by some that the present specifica- 

 tions for cod-liver oil, as stated in the United States Pharmacopoeia, 

 place the producers of haddock-liver oil at a distinct disadvantage; 

 although the intention of the Pharmacopoeia is to permit the use of 

 haddock-liver oil along with cod-liver oil. At the present time but a 

 very small portion of the domestic supply of fish livers is converted 

 into oil, and any stimulation toward increased production of domestic 

 liver oil would be of considerable service to the fishing industry. 



The scope of the investigation now under way includes a study of 

 the oil rendered from livers removed from haddock taken on all the 

 important fishing grounds during an entire year. The data which 

 are being correlated consist of: (1) Date of catch, (2) location of fish- 

 ing ground, (3) color of oil, (4) specific gravity, (5) refractive index, 

 (6) free fatty acid content, (7) unsaponifiable matter, (8) saponifica- 

 tion number, (9) iodine number, and (10) vitamin potency. 



The data obtained up to the present writing show that haddock- 

 liver oil is subject to considerable variation with regard to some of its 

 physical and chemical properties. Further, on the basis of the trend 

 of these data, which includes the period from September to Decem- 

 ber, some of these properties during the warmer seasons may be 

 expected to fall beyond the limits of the Pharmacopoeia. 



IMPROVING THE TECHNICAL USEFULNESS OF DOMESTIC FISH OILS 



One of the important problems facing the fish oil industry in this 

 country is to find a better market for its output. In order to be of 

 assistance to the fish oil industry in this connection, the bureau has 

 undertaken a study to relieve this situation. The work on this 

 problem at the present time is concerned with the natural variations 

 in the properties of the oils from different sources; since one of the 

 principal objections made by consumers of fish oils is their apparent 

 lack of uniformity. On the basis of the data obtained it is hoped, as 

 the first step, to be able to recommend when the various oils are most 

 nearly fitted for the many uses which can be made of them. 



