PASTEURIZATION 189 



time of exposure on each bottle, as well as the date on which 

 the milk was heated. 



Pure milk is better than purified milk 



It is self-evident that pasteurization is an expedient 

 and not an ideal. It must be quite evident to any one who 

 gives the matter thoughtful attention that the heating of 

 milk is like the use of antiseptics. Antisepsis was a great 

 improvement in surgery, but asepsis, or the absence of 

 germs, is the ideal. The surgeon however must have anti- 

 septics to attain asepsis. In the same sense the heating im- 

 proves bacteria-laden and infected milk, but clean milk is 

 the end we must seek. 



The question of obtaining a safe milk in the enormous 

 quantities necessary to supply large cities is so far from 

 solution that some milk experts believe that pasteuriza- 

 tion is not a temporary expedient, but will always be 

 necessary because it is economically justifiable for the milk 

 used by adults and for ordinary household purposes. This 

 opinion is perhaps justified because the heating of milk 

 does not injure its nutritive value. If the heating is prop- 

 erly done, pasteurized milk cannot be distinguished from 

 raw milk either by taste, odor, or appearance. Even labora- 

 tory tests cannot tell with certainty whether a milk has 

 been heated to 60 C. for twenty minutes or not; yet such 

 milk is free from the danger of conveying tuberculosis, 

 typhoid fever, diphtheria, scarlet fever, and dysentery, 

 and is safer for infants. 



Preventive measures are better than corrective ones v 



Milk should be produced under clean conditions and 

 kept clean, and then it would not have to be purified. But 

 we must guard against enemies so long as they exist. We 

 would all like to do away with the necessity for armies 

 and navies, but present conditions demand their main- 

 tenance. The same is true of the harmful bacteria in milk. 



