364 TESTS NECESSARY IN CREAMERIES 



white cup and the rinsings of the pipette added to the cream in 

 the cup. Three or four drops of phenolphthalein indicator are 

 then added to the sample. The lime water is then added from a 

 graduated cylinder or a burette until a delicate permanent pink 

 color is reached. So long as. the mixture remains colorless, acid 



FiQ. 121.— Dairy School students checking up their work by means of tlie Babcock test. 



predominates. When a constant pink color appears it may be 

 judged that the free acid has been destroyed by the lime water. 

 The quantity of lime water used may then be read from the 

 cylinder. The amount of acid in the cream will be indicated by 



