Fermentations in Milk. 79 



Overcoming taints by use of starters. Another method 

 of combatting abnormal fermentations that is often fruit- 

 ful, is that which rests upon the inability of one kind of 

 bacteria to grow in the same medium in competition with 

 certain other species. 



Some of the undesirable taints in factories can be con- 

 trolled in large part by the introduction of starters made 



FIG. 20. Curd from a badly tainted milk. Large ragged holes are mechanical; 

 numerous small holes due to gas. This curd was a " floater." 



from certain organisms that are able to obtain the ascend- 

 ency over the taint-producing germ. Such a method is 

 commonly followed when a lactic ferment, either a com- 

 mercial pure culture, or a home-made starter, is added to 

 milk to overcome the effect of gas-generating bacteria. 



A similar illustration is seen in the case of the " lange 

 wei" (slimy whey), that is used in the manufacture of 

 Edam cheese to control the character of the fermentation 

 of the milk. 



This same method is sometimes applied in dealing with 

 certain abnormal fermentations that are apt to occur on 

 the farm. It is particularly useful with those tainted milks 

 known as " sweet curdling." The ferment organisms con- 



