SOUR MILK 617 



There is no doubt that micro-organisms are far more 

 abundant in milk as supplied to the consumer than should 

 be. This arises from the ignorance and carelessness of 

 those charged with the duty of providing and distributing 

 this important article of diet. The udder and teats of 

 the cow and the hands of the milker (who should wear a 

 special dress) should be wiped before milking, and all 

 vessels should be clean and steamed or scalded before use. 

 The milk should be cooled at once, some more efficiently 

 closed vessel than the present form of milk churn adopted, 

 and the milk not stored, but forwarded without delay 

 by the railway companies in special refrigerator vans. 

 Distribution in bottles would be a great improvement. 



The following might be suggested as a bacteriological 

 standard for milk : * (a) Number of organisms not to 

 exceed 1,000,000 per c.c. ; (b) absence of excess of leu- 

 cocytes or of pus- cells ; (c) B. coli, B. Welchii, and strep- 

 tococci should not be present in 1 c.c. or less; (d) the 

 sediment after centrifuging should be less than 100 

 parts per million ; (e) the milk as delivered should not 

 have a temperature above 10 C. ; (/) absence of pathogenic 

 organisms. 



Sour milk. Sour milk is used as an article of diet in many parts 

 of the world, e.g. Bulgaria. In these sour milks a particular micro- 

 organism or a variety of it, the B. bulgaricus or " bacillus of Massol," 

 is generally present in association with lactic streptococci. It is 

 a large, pleomorphic, Gram-positive bacillus, non-motile, non- 

 sporing, growing best at about 40 C., but only in milk or in culture 

 media made with milk or whey. It has been much employed for 

 the preparation of a soured milk which is of considerable service 

 in the treatment of certain disorders. 2 



1 See " Rep. of a Committee on Milk Supply," Philad. Med. Journ., 

 October 1900, p. 758 ; Park, Journ. of Hygiene, vol. i, 1901, p. 391 ; 

 Houston, loc. cit. 



2 See Hewlett and others, Brit. Med. Journ., 1910, vol. ii (Bibliog.). 



