1912.] 



Ropy Milk. 



999 



2. Milk which is ropy at the time of milking may or may 

 not be due to the growth of bacteria ; but though it may not 

 cause an outbreak of this trouble, it should not be used for 

 food and should be regarded as more harmful than ropy milk 

 proper. 



3. In cases of garget or inflamed udders, special care should 

 be taken against the infection of other cows by the hands of 

 milkers, &c. 



4. With the exceptions mentioned in 2 and 3, ropy milk 

 is wholesome and does not endanger public health. 



5. The organism may come from water used for washing 

 dairy utensils, &c, or from water in which cows have been 

 standing, or which has otherwise been splashed on their 

 flanks or udders. 



6. The trouble may also come from dust and straw, as 

 well as from the butterwort and probably other plants. 



7. Some forms of ropy milk organisms grow at the tempera- 

 ture of cooled milk. 



8. Wooden vessels tend to encourage the persistence of the 

 trouble, as do also dilute solutions of soda if these are not 

 freshly made from boiling water. 



9. Most of the organisms require air for their growth, and 

 the cream layer, therefore, tends to go ropy before the lower 

 layers of the milk. 



10. Some forms of ropy cream make butter which quickly 

 goes rancid; but on the other hand other organisms are 

 prized as "starters " in the making of Edam cheese. 



Tests to be used in cases of Ropiness in Milk, — 1. It should 

 first be ascertained whether the outbreak is caused by bacteria 

 by adding a few drops of the affected milk to some sound new 

 milk in a clean glass. This glass should then be placed in 

 a warm room and kept loosely covered to prevent dust getting 

 in. The time taken for ropiness to appear should be noted. 



2. The cows should be examined, and samples taken in 

 clean glasses from the milk of individual cows and from 

 the mixed milk after straining, cooling, &c. The' time taken 

 in each case for ropiness to appear should be noted. 



3. To a glass of clean fresh milk from another source 

 should be added some of the water used for washing the 

 churns and pails and to another glass some of the water 



