98 THE MODERN MILK PROBLEM 



to indicate dirt.* Since the use of pasteurized milk is rapidly 

 increasing, the ultimate failure of the total count is obvious. 

 As to determining the number of B. coli and using the data 

 to indicate manure, this method will fail for the same reasons 

 that the total count must fail. In addition, the determina- 

 tion of B. coli requires rather too elaborate a technique to 

 make it generally available. Up to the present time the 

 method appears to have gained little favor. When the test 

 is made sufficiently early and before the milk is pasteurized 

 it has been shown f that the method is an excellent one for 

 the purpose. The dairy in which the method was applied 

 received its supply from a comparatively limited area and 

 from only twenty dairymen. Special endeavors were made 

 to produce only superior milk. 



At present the determination of visible dirt appears to be 

 in greatest favor and has proven itself a valuable asset to the 

 sanitarian in checking up supplies. The ease with which 

 the determination is made and the tell-tale nature of the 

 evidence presented speak highly in its favor. The Wizard 

 Sediment Tester J has proved very satisfactory in our hands. 

 Indeed the method leaves little to be desired so long as the 

 producer does not become wise and adopt clarification 

 methods such as heavier strainers or centrifugation. Ob- 

 viously the method will fail as soon as better clarification 

 methods are adopted. Such clarification cannot lessen the 

 number of manurial bacteria in milk or the soluble portion 

 of the manure, but rather aids in their better distribution. 

 From these considerations it is quite clear that we have no 

 method for determining manurial pollution which does not 

 fail at some critical point. The total count and B. coli deter- 

 minations fail in milk that has been held for some time or has 



* Except in that samples taken before pasteurization indicate general 

 sanitary quality. J. S. M. 



t Weinzirl, John, and Felder, H. A., unpublished data. 

 J The Creamery Package Mfg. Co., Chicago, 111. 



