Ropy Milk 377 



washed. The organism of ropy milk is frequently present 

 in water, and the latter may, therefore, become the source 

 of this milk fault. 



Ropy milk is harmless to those who consume it. 

 In some localities, the ropy-milk bacteria are even en- 

 couraged in their development, and the products of 

 their activities prized for their palatability. It is stated 

 that ropy whey is successfully utilized in Holland in 

 the preparation of Edam cheese. In Scandinavia, ropy 

 milk is artificially prepared by the rubbing of the in- 

 terior of milk vessels with the leaves of butter-wort, 

 a plant that harbors large numbers of ropy-milk bac- 

 teria. 



The cause of the ropiness is apparently not the same 

 for the different species producing this milk fault. It 

 is believed that some of the organisms make the viscous 

 substances out of the milk-sugar. This view is borne 

 out by experiments in which pure cultures of such bac- 

 teria were found capable of producing viscosity in so- 

 lutions of various sugars. Other species undoubtedly 

 bring about a ropy condition of the milk by causing 

 the decomposition of its nitrogenous substances, while 

 still others, by means of the mucilaginous sheaths 

 surrounding the bacterial cells, produce the same effect. 



