366 ANNUAL REPORTS OF DEPARTMENT OF AGRICULTURE. 



In addition to solving problems of a nonregiilatory nature de- 

 scribed elsewhere in this report, these laboratories collect data and 

 study methods to be employed in applying the terms of the food and 

 drugs act to products upon which necessary knowledge has been 

 lacking. 



FOOD CONTROL INVESTIGATIONS. 



The investigation on the composition of egg noodles referred to 

 in the last report was continued. The data obtained will be used 

 in the application of the law to products deficient in egg solids. 



A study of w^heat flour, its manufacture, grading, and use, was 

 continued. Special attention was given to methods for the deter- 

 mination of moisture in flour. About ninety commercial self-rising 

 flours were analyzed chemically and microscopically and subjected 

 to baking tests. Most of the samples examined were of satisfactory 

 quality. 



The sardine and clam packing industries in Maine and the oyster 

 industry in New Jersey were investigated. The entire time of one 

 chemist has been devoted to the development of chemical methods 

 for detecting spoilage in canned salmon. 



Considerable work was done on canned fruit and vegetables. The 

 technique for the quick detection of small quantities of carminic 

 acid, an added color in tomato products, has been perfected. 



An extensive experimental pack of canned grapefruit was pre- 

 pared by the Savannah and Porto Rico stations. This is now being 

 examined and its keeping qualities in tin observed. 



Authentic samples of malt extracts were analyzed, with a view 

 to differentiating between an all-barley malt extract and one made in 

 part from corn. The determinations made do not show any char- 

 acteristic differences between the different kinds of extracts from a 

 chemical standpoint. Much work was done on dairy products. 



STOCK FOODS. 



Studies to determine standards and definitions for various cattle 

 feeds sold on the American market w^ere continued. Attention was 

 given to flour by-products and an information sheet on the subject 

 was issued. Work was done on oat and meat by-products as feeds. 

 Studies on the milling of buckwheat and barley are under way. An 

 investigation of the manufacture of precipitated bone and of its mer- 

 its as a mineral constituent of mixed feeds was made. A method for 

 determining the presence of starch in linseed meal and similar ma- 

 terials containing interfering polysaccharides has been developed 

 and published. A study of the composition of grain sorghums was 

 completed. 



Work on the utilization of waste by-products as cattle foods was 

 continued. Department Bulletin 1166, Apple By-Products as Stock 

 Foods, has been issued. 



MICROBIOLOGICAL INVESTIGATIONS. 



An investigation of oyster spoilage was made. Because of the 

 perishable nature of oysters and the fact that they are often shipped 

 for long distances, studies were made to determine the effect of time, 

 temperature, and methods of handling upon the keeping quality of 



