368 ANNUAL REPORTS OF DEPARTMENT OF AGRICULTURE. 



Special attention was given to determining the cause of swells in 

 canned sauerkraut and the proper procedure in canning to prevent 

 this difficulty and at the same time produce the most desirable 

 product. In this work No. 3 cans, subjected to a 10-minute exhaust 

 in steam during the canning process without further processing, 

 were sterilized. They were much less subject to swell than were 

 cans handled in the ordinary commercial manner, which usually in- 

 cludes a very short exhaust and a very short process in the retort. 

 Cans handled in the ordinary commercial manner were found to be 

 unsterile and in most cases produced gas and corroded the metal of 

 the container. 



The work done upon soy sauce fermentation was published as 

 Department Bulletin 1152, Soy and Related Fermentations. 



MICROCHEMICAL INVESTIGATIONS. 



An investigation of decomposition in filberts imported from Italy 

 was made. Experimental work was continued on the decomposition 

 of small fruits, especially cherries and strawberries, both in the 

 field and in the laboratory. The manufacture of apple butter was 

 studied and a general survey of apple butters on the market was 

 made, with a view to determining the quality of the various materials 

 employed. An investigation of the pollen in honey was continued. 

 Investigational work is in progress to determine what effect the 

 fineness of the grind has on calculating the quantity of cacao shell in 

 cacao products. Work on tomato products was continued. 



The method on the microscopical examination of flour referred 

 to last year has been simplified and the new method is described in 

 Department Bulletin 1130, Significance of Wlieat Hairs in Micro- 

 scopical Examination of Flour. 



The results of a crystallographic study of the calcium oxalate 

 crystals in official plant drugs have been published in collaboration 

 with the Laboratory of Crop Chemistry. 



The preparation of a table of optical constants of various organic 

 crystalline compounds is in progress. 



A large number of flour and feed mills in the Middle West have 

 been visited to obtain information on the source and methods of 

 handling grain by-products used in feeds. The handling of pack- 

 ing-house by-products was also studied. 



WATER AND BEVERAGE CONTROL. 



Sanitary surveys of certain springs from which mineral waters are 

 sold were made. A method for the examination of imitation grape 

 flavors was perfected. Several samples of alleged radioactive pads 

 and of water and drugs, the labels of which bore statements that 

 the products contained radium, were analyzed. 



In the interest of the shellfish industry, trade waste surveys were 

 made of the Housatonic River and the New Haven Harbor, Conn., 

 in cooperation with the Bureau of Fisheries. 



Methods were developed for the manufacture of flavoring sirups 

 and extracts from cassina leaves. An investigation of the suitability 

 of various solvents for extracting vanilla beans was begun. 



