160 Dairy Bacteriology. 



The thin layer of paraffin excludes the moisture from the 

 wood, and also prevents the mold from obtaining a sup- 

 ply of oxygen for its growth. The tubs may be steamed, 

 treated with hot water, or filled with a dilute solution of 

 formaldehyde, and allowed to stand overnight. Soaking 

 in brine as is usually done in the creameries is of some 

 effect, but will not completely kill mold spores. 



.Butter may mold where the tubs have been thoroughly 

 treated, because of the mold spores on the paper used for 

 the lining. One of the black molds is able to thrive on 

 parchment paper whenever the air is damp. In the past 

 but little attention has been paid to the paper as a source 

 of trouble. It is certain that it is often at fault, and 

 that as much attention should be paid to the paper as 

 to the tub. A most efficient way of treating paper, ei- 

 ther for tub liners or print wrappers is to place same in 

 boiling water for a few minutes. 



