66 MODERN METHODS OF TESTING MILK 



OUTLINE STATEMENT OF SOME SPECIAL 

 PRECAUTIONS 



1. Always make tests in duplicate. 



2. Make sure that the sample is a representative one. 



3. Have the temperature of the milk and acid at 

 60° to 70° F. before putting in test-bottle. 



4. Use only acid of right strength. 



5. Alix milk and acid thoroughly as soon as acid 

 is added. 



6. ]\Iix a second time after a short interval. 



7. Alake sure that the tester runs at right speed 

 and does not jar. 



8. Use only clean, soft water in filling bottles. 



9. Read bottles before they cool and at about 130° F. 



10. To insure accuracy, read each test twice. 



SOME MODIFICATIONS OF THE BABCOCK TEST 



One frequently sees references in dairy literature 

 to other forms of tests for milk. As a matter of in- 

 iormation, we will notice a few of the modifications of 

 the Babcock test together with other forms that are 

 in use, giving good results. 



The Russian Test. — This is a modification of the 

 Babcock test, differing mainly in respect to some of 

 the mechanical details. A special automatic pipette is 

 used (Fig. 28), a special form of test-bottle (Fig. 28a), 

 the neck being separate from the rest of the bottle, and 

 also a special form of acid-measure. The pipette and 

 acid-measure are one-half the usual size. The milk and 

 acid are run into the bottle very easily, and the bot- 

 tles are filled with hot water automatically while the 

 machine is in motion, the tester also being of a special 

 form. 



