MILK AND ITS PRODUCTS 



175 



so that the amount of acid can be calculated from the 

 amount of alkali used. 



Harrington's Alkaline Tablet Test. In this test the 

 alkali is used in a dry tablet form in which it is easily 

 handled. Each tablet contains enough alkali to neutralize 

 .034 gram of lactic acid. 



Apparatus Used for the Test. This is shown in Fig. 

 48, and consists of a porcelain cup, one 17.6 c.c. pipette, 

 and a 100 c.c. rubber-stoppered, graduated glass cylinder. 



PIPETTE 



Fig. 48. Farrington Acid Test Apparatus. 



Making the Solution. The solution is made in the 

 graduated cylinder by dissolving 5 tablets in enough water 

 to make 97 c.c. solution. When the tablets are dissolved, 

 which takes from six to twelve hours, the solution should 

 be well shaken and is then ready for use. The solution 

 of the tablets may be hastened by placing the graduate in 

 a reclining position, as shown in the cut. 



