EEPORT OF THE ACTING CHEMIST. 



U. S. Department of Agriculture, 



Bureau of Chemistry, 

 Washington, D. C, September 2, 1912. 



Sir: T have the honor to transmit herewith the annual report of 

 the Bureau of Chemistry for the 3^ear ending Jime 30. 1912, together 

 with the plans for the work proposed for the next fiscal year. 

 Respectfully, 



E.. E. DOOLITTLE, 



Acting Chief of Bureau. 

 Hon. James Wilson, 



Secretary of Agriculture, 



FOOD INVESTIGATIONS. 



SPECIAL INVESTIGATIONS OF THE DIVISION OF FOOOa. 



Canned Foods. 



The study of the canning of food products for the purpose of 

 improvement in quality and processes of manufacture, as well as the 

 securing of information for the enforcement of the food and drugs 

 act, has been continued during the past year. The results of the 

 investigations as far as completed have been assembled in popular 

 form in Chemistry Bulletin No. 151, which gives a description of 

 the conditions and the methods followed in the better type of fac- 

 tories. The study of the quantity of material in each can and the 

 degree of temperature and length of time for proper processing 

 makes this work of especial interest to the canners. 



The work now in progress involves a detailed study of the can- 

 ning and preserving of fruits, especially in California. The num- 

 ber of questions involved are so numerous and some of them so com- 

 plicated that a special laboratory has been equipped for this work. 

 It is in fact a miniautre canning and ])res('r\inir factory, duplicating 

 on a small scale the equipment used in the best commercial plants; 

 it is provided with its own steam plant, sterilizers, retorts, exhauster 

 can-capping machines, various styles of jacketed kettles, two vacuum 

 pans, cooking coils, vacuum and pressure pump, vacuum glass sealer, 

 hydraulic press, clnrifier, and various testmg apparatus. A bacte- 

 riological laboratory is attached to study the organisms normally 

 present on tlie fresh products and those present in decay. The 

 chemical work is carried on in the San Francisco food and drug 

 inspection laboratory. 



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