68 



FIRST LESSONS IN DAIRYING 



cumstances permit. Doctor Conn has shown that at 

 a temperature of 50 bacteria multiplied five times 

 in 24 hours, while at 70 they multiplied 750 times.* 

 Cooling may be done by surrounding the can of 

 milk with cold water or running it over a cooler 

 through which cold water is flowing. Most coolers 

 are also aerators, exposing the milk to air. If this 

 aeration is done where the air is free from dust and 



CHAMPION MILK COOLER AND 

 AERATOR 



CHAMPION COOLER AND AERATOR, 



SHOWING INFLOW AND OVERFLOW 



FOR RUNNING WATER 



odors, it is usually an advantage, permitting as it 

 does the escape of gases more or less commonly 

 present in the milk. It has been pretty conclusively 

 shown that much of the so-called "cowy odor" is 

 due to manure in the milk. 



Care of hand-separator cream. The marketing of 

 the dairy product of the farm as cream is one of 

 the most convenient methods available, involving 



*See "Practical Dairy Bacteriology," by Dr. H. W. Conn, 

 published by Orange Judd Company, 1907. 



