BUREAU OF ANIMAL. INDUSTRY. 237 



started a movement which will eventually do much to raise the quality 

 of the Chicago milk supply. 



At the request of the Bureau of Chemistry in connection with its 

 work of administering the food and drugs act, the Dairy Division 

 has inspected and scored dairies producing milk for interstate ship- 

 ment and whose product did not conform to the law. 



A draft of a milk law recommended as applicable to most regions 

 has been sent on request to many persons interested in procuring 

 such legislation. 



A paper on '" The Care of Milk in the Home " was prepared during 

 the fiscal year and has been published in a Farmers' Bulletin. 



The Dairy Division has also assisted the movement for better milk 

 by lending for various exhibitions large photographs showing good 

 and bad dairy conditions. 



RESEARCH LABORATORIES. 



The research laboratories, in charge of Mr. L. A. Rogers, are 

 devoted to experimental work, largely of a bacteriological and chemi- 

 cal character, with special reference to the study of processes em- 

 ployed and problems arising in the manufacture of dairy products. 

 Besides the main laboratory in Washington there is a branch labora- 

 tory at Albert Lea, Minn., devoted to butter and Swiss cheese investi- 

 gations. In addition, cooperative investigations with state experi- 

 ment stations are being carried on at Storrs, Conn.; Madison, Wis.; 

 and Columbia, Mo. 



BUTTER INVESTIGATIONS. 



Various problems relating to butter are being studied. More recent 

 work has confirmed the results of earlier experiments in showing the 

 superiority of butter made from sweet cream for storing purposes, 

 and particularly when stored at a comparatively high temperature. 

 In continuing this work, butter for storage is being made in three 

 ways — from pasteurized sweet cream, from pasteurized ripened 

 cream, and from ripened raw cream. Portions of each lot are stored 

 at zero, 10° F., and 20° F. The butter is scored when put in storage 

 and again when taken out six months later. 



Experiments have been made to determine the proper temperature 

 for pasteurizing cream for butter making. Various temperatures 

 from 140° to 200° F. were used. Results show that an efficient tem- 

 perature from a bacteriological standpoint varies with the condition 

 of the cream, but that 1G0° F. seems to give the best results. The 

 scores of butter made from cream pasteurized at from 160° to 180° F. 

 seem comparatively uniform, but are variable below that range, and 

 the butter has a scorched 'flavor above it. 



The relative cost of making butter from pasteurized and un- 

 pasteurized cream is being investigated. For a period of one week 

 all the cream is pasteurized before it is churned. The next week it 

 is churned raw. For 19 periods this work has been in progress, and 

 it will bo continued. 



Much of the cream used in some creameries is very sour when it 

 reaches the creamery, and in order to get rid of the excess of acid it 

 is neutralized with lime. The detection of such butter is desirable, 



