FARM DAIRYING 



well withhold food, but we expel moisture from 

 meat, fruit, etc., to preserve them. We cool milk 

 and place perishable foods in refrigerators for 

 no other reason than to hold in check the bacterial 

 growth, and so retard the souring or decompos- 

 ing process. 



The most favorable temperature for bacterial 

 growth is between 80 and 100 degrees. The aim 

 in caring for milk should be to lower the tempera- 

 ture quickly and keep it low, if the desire is to have 

 the milk remain sweet. At a temperature below 

 50 degrees, bacterial growth is practically at a 

 standstill. A temperature of 160 degrees kills 

 most of them if it be maintained for twenty min- 

 utes. Instantaneously heating to 185 degrees 

 destroys all but a few of the resistant spore 

 formations. 



Some three thousand different species of bacteria 

 have been identified. Most of them are helpful 

 agents in the world's economy. Some are unde- 

 sirable, but not dangerous. Others are harmful 

 and cause death when not checked. 



So many of these disease-producing germs find 

 a perfect medium for their development in milk 

 that too much care cannot be exercised to keep 

 the milk pure. When any contagious disease 

 breaks out in a family, those who are recovering 



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