2 12 MILK AND THE PUBLIC HEALTH chap. 



28 cases ( = 87 per cent), while B. enteritidis sporogenes was 

 present in about half the samples. 



Dold and Garratt ^ found that while bacilli were invariably 

 present, the number was, on the whole, much smaller than 

 that usually found in the same quantities of ordinary market 

 milk. £. coli commionis and £. enteritidis spo7'ogenes were 

 found to be absent from 1 c.c. of the condensed milk in all 

 the 19 samples examined. Streptococci were found in 1 c.c. 

 in 8 cases (32 per cent), in O'l c.c. in 3 cases. Pathogenic 

 organisms could not be detected in any of the samples, either 

 by microscopic examination or animal inoculation. 



Gordon and Elmslie' examined samples of 15 different 

 brands of condensed milk, 5 consisting of full cream sweetened 

 milk, 4 of full cream unsweetened milk, and 6 of machine- 

 skimmed sweetened milk. None of the samples were sterile. 

 The 4 unsweetened milk samples contained no organisms that 

 were likely to have existed in the original milk before con- 

 densation, streptococci, £. coli group organisms, and spore-bear- 

 ing anaerobes all being absent. Streptococci with characters 

 similar to those found in milk were present in all the 11 

 sweetened samples. These investigators concluded that while 

 in the process of condensing of unsweetened milk sterility is 

 secured, the organisms found being subsequently introduced 

 from the air, in the condensing of sweetened milk sterility is 

 not attained, some at least of the organisms in the original 

 milk surviving the process of condensation. No organisms of 

 the B. coli group were isolated from any of the samples. 



Deldpine^ specially investigated the resistance of tubercle 

 bacilli to the processes involved in the preparation of 

 condensed milk. Fresh cows' milk was used mixed with milk 

 rich in tubercle bacilli obtained from a tuberculous cow and 

 with milk artificially infected with bovine tubercle bacilli. 

 The mixture was condensed in a milk factory, the whole of 

 the processes being carried out exactly in accordance with the 

 usual procedure of manufacture. Del^pine made inoculation 

 experiments with the milk obtained at various stages of the 

 condensing process and with the finished product. Although 



1 Journ. Royal Inst. Public; Health, 1910, xviii. p. 294. 

 ^ Report by Dr. Coutts to Local Government Board om Condensed Mill; 1911. 



3 Ibid. 



