312 



CITY MILK SUPPLY 



the doctrine that it offers absolute protection against this or any other 

 disease is to deceive. Pasteurization is a mechanical process operated 

 by men and in this imperfect world both fail at times, so that a very high 

 degree of protection is the most that can be honestly promised. The 

 process may be likened to the mechanical nitration of water; this sort of 

 water treatment when operated efficiently with machinery in first-class 

 condition is capable of materially reducing water-borne diseases, but if 

 the apparatus breaks down or is allowed to get into Condition unfit for 

 use or if it is either incompetently or dishonestly operated it will fail 

 in greater or less degree according to the gravity of the injury or 

 mismanagement. 



Pasteurization of milk is accepted as a necessary treatment of the 

 public milk supply not because it is ideal but because it is practicable. 

 When the pasteurization is done right and the milk protected against 

 subsequent infection and when the pasteurized milk is marketed on its 

 merit without extravagant claims in its behalf the process is a great boon 

 to the milk consumer, but when the milk is pasteurized in any old way 

 that will prevent souring, or when milk is pasteurized over and over again 

 before the consumer gets it, or when pasteurization is used as a club to 

 kill off inspection of dairy farms or tuberculin testing or any other legiti- 

 mate phase of control of the milk supply, it can be made a curse instead of 

 a blessing. The process probably has enough intrinsic merit to survive 

 any abuse to which it is likely to be subjected but if dairymen and their 

 customers are to enjoy in full the benefits it is capable of conferring it 

 must be used honestly under severe inspection. 



Use of Pasteurization in the United States. The general tendency 

 in the United States at the present time is toward the pasteurization of 

 all market milk except that which is certified and that which comes 

 from tuberculin-tested herds. This trend may be observed in Tables 87 

 and 88. 



TABLE 87. THE EXTENT OP USE OF PASTEURIZATION IN CITIES OF THE UNITED STATES 

 OF A POPULATION ABOVE 25,000 (AYRES) 



