24 



THE STORY OF MILK 



in milk at ordinary room temperature, 68° to 70°, 

 which emphasizes the importance of keeping milk cool. 



If the milk had contained 1,000 bacteria per cubic 

 centimeter at the beginning, the part held at 50° F. 



Milk cooler 



The diagram (after Conn) shows the 

 rapidity with which bacteria multiply 

 in milk not properly cooled. A single 

 bacterium (a) in 24 hours multiplied to 

 5 (b) in milk kept at 50° F. ; (c) repre- 

 sents the number that develop from a 

 single bacterium in milk kept 24 hours 

 at 70° F. 



would have contained 4,100 bacteria at the end of 24 

 hours, while that held at 68° F. would have contained 



