66 A DAIRY LABORATORY GUIDE 



EXERCISE XIII 



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. Using 

 the whole milk test bottle, test the sample 

 in duplicate by the Babcock method. Com- 

 pare 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. 

 S- Test for salt a sample of butter using 10 grams 

 of butter and 300 cc. of water. Titrate sev- 

 eral 17.5 cc. portions of the water and check 

 results carefully. 



