66 A DAIRY LABORATORY GUIDE 



EXERCISE XII 



BABCOCK TEST, LACTOMETER AND ACID 

 TEST 



1. Test by the Babcock method a sample of whole 



milk, cottage cheese and buttermilk. Fill 

 your lightning top sample jar about one-third 

 full of whole milk, add a preservative tablet 

 and shake at intervals until tablet is dis- 

 solved. Set the sample away in your desk 

 and test at the next exercise. 

 Use 9 grams of cottage cheese, and add 9 grams 

 of water. Test in whole milk bottle. Shake 

 well after adding acid. 



2. To about 54 grams of skimmed milk add 2 cc. 



of light machine oil, shake thoroughly and 

 test in duplicate by the Babcock method. 

 Compare the appearance of the fat column 

 with that obtained with ordinary butter. 



3. Test with the alkali tablet solution the acid in 



the whole milk and buttermilk. 



4. Take a lactometer reading of the whole milk. 



Add some water (about 25 cc.) to the 

 sample. Again take a lactometer reading 

 and make a Babcock test. Figure out T. S. 

 and S. N. F. and the per cent of the water 

 added. 



