CANNOT BE FILTERED OUT 19 



BACTERIA CANNOT BE FILTERED OUT 



Dirt and bacteria travel together. Because the 

 strainer removes dirt, some think it removes 

 bacteria. The fact is that the finest strainer 

 used by dairymen removes only the very coarse 

 dirt, and leaves still in the milk all of the fine 

 dirt. Bacteria are much smaller than even the 

 finest dirt, and easily pass through the strainer 

 with the milk. 



The cheese cloth or wire commonly used for 

 straining is 32 meshes to the inch. The finest 

 cheese cloth that can be purchased has 64 meshes 

 to the inch. Under a magnifying glass the meshes 

 of fine cheese cloth appear very large. Since 

 it takes 25,000 bacteria to cover I inch in length, 

 400 bacteria could be placed in a row in the 

 space between two threads of the finest cheese 

 cloth, and through one of the square openings 

 of such a cloth a regiment of 160,000 bacteria 

 could march abreast. 



Bacteria are much smaller than the drops of 

 butter fat in milk, therefore a strainer fine enough 

 to remove bacteria would also remove all of the 

 butter fat, and allow only skim-milk to pass 

 through. 



