Fermentations in Milk. 71 



causal organism seems to be B. lactis viscosus. a form first 

 found by Adametz in surface waters. 1 This organism pos- 

 sesses the property of developing at low temperatures 

 (45-50 F.), and consequently it is often able in winter 

 to supplant the lactic-acid forms. Ward has found this 

 germ repeatedly in water tanks where milk cans are cooled; 

 and under these conditions it is easy to see how infection 

 of the milk might occur. Marshall 2 reports an outbreak 

 which he traced to an external infection of the udder; in 

 another case, the slime-forming organism was abundant 

 in the barn dust. A defect of this character is often per- 

 petuated in a dairy for some time, and may therefore be- 

 come exceedingly troublesome. In one instance in the 

 writer's experience, a milk dealer lost over $150 a month 

 for several months from ropy cream. Failure to properly 

 sterilize cans, and particularly strainer cloths, is frequently 

 responsible for a continuance of trouble of this sort. 



The slimy substance formed in milk comes from vari- 

 ous constituents of the milk, and the chemical character 

 of the slime produced also varies with different germs. In 

 some cases the slimy material is merely the swollen outer 

 cell membrane of the bacteria themselves as in the case of 

 B. lactis viscosus; in others it is due to the decomposition 

 of the proteids, but often the chief decomposition product 

 appears to come from a viscous fermentation of the milk- 

 sugar. 



An interesting case of a fermentation of this class being 

 utilized in dairying is seen in the use of u langewei" 

 (long or stringy whey) which is employed as a starter in 

 Holland to control the gassy fermentations in Edam cheese. 



1 Adametz, Landw. Jahr., 1891, p. 185. 



2 Marshall, Mich. Expt. Stat., Bull. 140. 



