Babcock Test for other Milk Products. 97 



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. 1 A brief description of the manipulations 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 cc. pipette full is 

 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 centrifuge. 



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- 

 bottle chamber of some machines, or by means of a 

 valve and pipe which will allow steam to be turned di- 

 rectly into the test bottle chamber. After this first 

 whirling the test bottles are taken from the centrifuge 

 and by being careful not to break the lump of curd 

 nearly all the whey or sugar solution can be poured out 

 of the neck. Ten cc. of water are then poured into the 



1 Wis. exp. station, report XVII, pp. 

 7 



