METHODS OF REDUCING THE GERM CONTENT 



539 



one of the milk bottles. Experience has shown that home treat- 

 ment of water or milk is not always successful. For the greater 

 part of the population, milk pasteurized on a large scale is prob- 

 ably the safer milk. 



Directions for home pasteurization of milk are given by Rogers 

 as follows: A small pail with a perforated false bottom is used. 

 An inverted pie tin with a few holes punched in it answers the 

 purpose. The bottles of milk are placed on this false bottom and 



Fig. 219. Desirable arrangement for 

 pasteurizing milk for infants' use. 



Fig. 220. An especially con- 

 structed pail devised in dairy labo- 

 ratory for efficient pasteurizing and 

 cooling of milk. Can be made by 

 any tinner. 

 (Frandsen in Bull. No. 39, Univ. of Neb. Agri. Exp. Sta.) 



a good thermometer inserted into one of the bottles. The pail is 

 filled with water nearly to the surface of the milk, and heated until 

 the thermometer shows a temperature of not less than 145 F. 

 nor more than 150 F. (Figs. 219, 220). The bottles are then re- 

 moved and covered with a towel to hold the temperature for 

 twenty to thirty minutes. The milk is cooled by placing the 

 bottles first in warm water to avoid breakage and then in cold 

 water. Lastly they are placed on ice. A wire basket can be used 

 to hold the bottles, as shown in Fig. 221. In this case the bottles 



