i84 FERMENTATION IN MILK 



milk-pails with the leaves of the Bog violet {Pingincula vulgaris). 

 It is probable that the action is due to the infection of the milk 

 by a micro-organism which finds its general habitat in the leaf 

 rather than to any peculiar property of the plant itself 



Mention ought to be made whilst on the subject of Diseases of 

 Milk, of the Bacillus lactis niger of Gorini.^ The authors have, 

 however, been unable to trace any authentic evidence of any 

 coloration in milk due to this organism, which would seem to be 

 nearly allied to, if not identical with, the Bacillus aterrimus of Biel. 



The Prevention of Milk Anomalies 



The measures to be taken in order to check and put an end 

 to any of the above pests of the dairy industry should present 

 no difficulty to the dairy bacteriologist, although if the origin of 

 the infection is traceable to the byre rather than to the dairy, 

 drastic measures may be found necessary. 



The first step should be a thorough examination of both dairy 

 and byre — the latter at milking time and without notice to the 

 attendants. The general state of the byre — the litter, fodder — and 

 cleanliness or otherwise of the cows and their milkers should be 

 carefully observed, and deductions drawn therefrom. 



In the dairy, the general cleanliness both of utensils and their 

 surroundings should be noted and, if the outbreak can be traced 

 to no other cause, a careful examination of the water used in 

 cleansing utensils should be made. A portion of the milk from 

 each milking for some days, taken both at the time it leaves the 

 byre and at an interval of some hours after its admission to the 

 dairy, should be set aside in a sterile test-tube, and its condition 

 and changes carefully watched. In the case of bitter cream or 

 butter, a portion of the cream at each churning should be pre- 

 served, and should the resultant butter prove of bitter flavour, 

 this must be examined, and the organisms therein compared 

 with those of the butter itself This pest in particular is of such 

 an intermittent nature, that unless this precaution is taken great 

 difficulty may be experienced in isolating the particular organism 

 acting as causation of the disease. 



The following measures, which are the result of the personal 

 experience of the authors, will be rarely found to fail to eradicate 

 completely any of the above pests, even in cases when they would 

 appear to have become firmly established. 



Byres. — These should be thoroughly cleaned out, every trace of 

 ' Centralb.f. Bakt., xx. 94. 



