THE EXAMINATION OF MILK 423 



bring about required changes in the milk. Green mould 

 {Penicilliwni glaucum) is the chief agent employed in the 

 ripening of Koquefort, Stilton, and Gorgonzola cheese, 

 Moulds also play an important part in the production of 

 Brie and other soft cheeses ; the growth of certain organisms 

 is encouraged upon the surface of these cheeses, so that the 

 special ferment which they produce can penetrate the body 

 of the cheese and bring about certain characteristic changes. 

 A certain yeast is used in the production of kephir (the- 

 national drink of the Caucasus), which is made by the^ 

 fermentation of cows' milk, similar to koumiss, which is- 

 produced by the fermentation of mare's milk. White^ 

 mould {OidiuTu lactis) is very frequently met with in milk 

 and other dairy products. When the milk becomes sour, 

 a white thick skin is found on the surface, which is wholly 

 formed of the mycelia and hyphse of this mould. 



In the report of a special analytical and biological com- 

 mission on milk-supply, held under the auspices of the 

 British Medical Journal (1895), the following reforms 

 were suggested by Rowland for the better management 

 of dairies, to secure a pure milk-supply : 



1. That all milking be carried on in the open air, the 

 animals and operators standing on a material which is 

 capable of being thoroughly washed, such as a floor of 

 concrete or cement. Such a floor could be easily laid down 

 in any convenient place which can be found. The site 

 chosen should be removed from inhabited parts as far as 

 possible, and should be provided with a plentiful water- 

 supply. Only in this way does it seem possible to avoid 

 the initial contamination with the colon bacillus. 



2. That greater care be expended on the personal cleanli- 

 ness of the cows. The only too familiar picture of the 

 animal's hind-quarters, flanks, and side being thickly 

 p astered with mud and faeces is one that should be 



