DAIRY LABORATORY GUIDE 



EXERCISE 1 



OPERATION OF THE BABCOCK TEST 



Object: To determine the percentage of butter-fat in 

 dairy products by the Babcock method. 



Apparatus: Samples to be tested, two milk bottles, 17.6 

 c. c. pipette, acid measure, beaker, tester, acid, and water. 



Steps: 1. Number the test bottles 1 and 2. 



2. Mix the samples well by pouring from one beaker to 

 another; then measure into each bottle with the pipette 17.5 

 c. c. of the milk. 



3. Add 17.5 c. c. of sulfuric acid to each bottle and mix 

 well by rotary motion until all of the curd is thoroughly 

 digested. 



4 . Put the bottles into 

 the tester and whirl at full 

 speed for two minutes. It 

 may be necessary to whirl 

 longer. 



5. Add hot water to 

 each until the butter-fat 

 rises to the neck of the 

 bottle. 



6. Whirl again at full 

 speed for two minutes. 



7. Add hot water until the butter-fat rises half way up 

 the neck of the bottle; then whirl one minute and read 

 the test. 



8. Always read each test carefully and record all data 

 accurately in the exercises that follow. 



Reading the Test. The whole-milk test is read from the 

 extremes of the top meniscus to the bottom of the fat column, 

 as indicated by Nos. 1 and 2, Fig. 8, page 50. 



7. Proper method of filling the test 



"ig. 7. 

 bottle. 



