ROPINESS IN MILK AND CREAM. 



BY ARCHIBALD R. WARD. 



Ropiness in milk is one of the most serious troubles with which 

 milk dealers have to contend. This condition which is objection- 

 able more on account of its unwholesome appearance than from 

 any known harmful effect which it produces, has received its pop- 

 ular designation from the viscid, slimj^ consistency which char- 

 acterizes the affected milk. The cause has been found to be 

 the action of certain bacteria, and a number of apparently dif- 

 ferent species have been described as possessing the power of pro- 

 ducing the ropy condition. Among those who have written on 

 this subject should be mentioned Adametz, Loeffler, Guillebeau 

 and Marshall. Nevertheless, few definite determinations have been 

 made concerning the natural habitat of these particular species of 

 bacteria and the channels through which they gain entrance to 

 the milk. Further information on these points is especially 

 desired in order to successfully combat the trouble and to pre- 

 vent its recurrence. 



This trouble which is wide spread and of considerable economic 

 importance to milk dealers and butter makers, should not be con- 

 fused with the abnormal changes in milk which accompany an 

 inflamed condition of the udder frequently called "garget." 

 Milk drawn from udders in this condition is more or less thickened 

 by the presence of pus or may in addition contain white, tough, 

 solid masses of casein which pass through the duct of the teat 

 with more or less difficulty. Milk in such condition is by some 

 called ropy and consequently it has been asserted that a diseased 

 condition of the udder is the cause of all ropy milk. The inves- 

 tigations which have heretofore been made do not throw any 

 definite light upon this alleged cause. They do not suggest a 

 necessary dependence upon a diseased condition of the udder, 

 although they do not preclude the possibility of such a combina- 

 tion. The fact that each of the authors referred to was able to 

 isolate a species of bacteria capable of producing this trouble 

 under artificial conditions, suggests that its source is very likely 



