PRESERVATIVES 299 



purposes. In Budde's process of sterilization, the milk 

 is heated to 48 or 50 C, and to it is added .035 per 

 cent, (about I 2 c.c. of a 3 per cent, solution) of hydrogen 

 peroxide. After keeping the milk at this temperature 

 for half an hour, during which time it should be stirred 

 or gently agitated, the temperature is raised to 52 C., 

 and this degree of heat maintained for two or three 

 hours. The milk is subsequently cooled rapidly, and 

 sent out in sterile bottles. 



The chief objections to the use of hydrogen peroxide 

 for this purpose are these : 



(a) A very small amount of the compound remains 

 undecomposed in the milk, and the effect of this upon the 

 health of small children is not known with certainty. 



(fr) Comparatively minute quantities give the milk a 

 taste which is disliked by some persons. 



(c) Much of the hydrogen peroxide which is sold 

 contains traces of hydrochloric acid, 'arsenic, and barium 

 compounds, and the pure solution is too expensive at 

 present for general use. 



