Babcock Test for other Milk Products. 99 



1:1). He finds that this aids in giving a clear separa- 

 tion of the fat and obtaining satisfactory results. 1 



107. Sweetened condensed milk. The testing of 

 sweetened condensed milk presents peculiar difficulties, 

 whether it is to be tested by the Babcock test or by 

 chemical analysis. It may, however, be readily tested 

 by the Babcock test by introducing certain changes in 

 the manipulation of the test, as worked out by one of 

 us. 2 A brief description of the method of analysis 

 adopted is here given. 



About sixty grams of condensed milk are weighed 

 into a 200 cc. graduated flask, to this 100 cc. of water 

 are added and the solution of the condensed milk ef- 

 fected. The flask is then filled to the mark with water 

 and after mixing thoroughly, a 17.6 pipette full of 

 measured into a Babcock test bottle. About three cc. 

 of the sulfuric acid commonly used for testing milk are 

 then added and the milk and acid mixed by shaking the 

 bottle vigorously. The milk is curdled by the acid, and 

 the curd and whey separated somewhat. In order to 

 make this separation complete and to compact the curd 

 into a firm lump, the test bottle is whirled for about six 

 minutes at a rather high speed (1,000 rev.) in a steam- 

 heated turbine tester. 



The chamber in which the bottles are whirled ought 

 to be heated to about 200 F. This can be done either 

 by the turbine exhaust steam which leaks into the test- 



1 For analysis of unsweetened condensed milk, see also Jr. Ind. and 

 Eng. Chem., 1913, pp. 131 and 168. Good results may be secured by 

 adding 3 cc. of a mixture of equal parts of amyl alcohol and C. P. 

 hydrochloric acid to the milk, then 10 cc. of C. P. sulfuric acid, and 

 proceeding as given above (Amott). 



2 Wis. exp. station, report XVII, pp. 86-89. 



