DAIRY FACTORY PREMISES. 15 



premises. A favourable breeze would carry a fine spray of this polluted 

 water through the factory. Then, since the diameter of the culture plate is 

 3 inches, into which at least 4,961 micro-organisms had fallen in fifteen 

 minutes, some idea might be gained as to the extent to which cream and 

 butter is subject to contamination with undesirable organisms from such a 



source. 



PLATES (B, C, D, E, AND F) EXPOSED TO ATMOSPHERE TO SHOW 



EXTENT OF MOULD INFECTION WITHIN THE FACTORY. 



B. An acid agar plate exposed to the atmosphere in the cream 

 attemperator room for five minutes, and after incubation for four days, 

 developed a total of thirty-six colonies of micro-organisms. Of these, twelve 

 were yeasts, three Micrococcus rosens T., one colony was of a sporing 

 bacillus, while the twenty mould growths were as follows : Cladosporium 

 sp. 9; Aspergillus sp. 2; Fusarius sp. 1 ; Spicaria sp. 6; Cephalosporium sp. 2. 



C. An acid agar plate exposed to the atmosphere in the churning room 

 for five minutes developed thirty-nine mould growths and four colonies of 

 yeast. Following are the moulds : Cladosporium sp. 23; Penicillium sp. 12 ; 

 Epicoccum sp. 2 ; Aspergillus sp. 2. 



D. Ordinary agar plate exposed to the atmosphere in the butter- working 

 room for five minutes developed a total of thirty-two colonies of micro- 

 organisms. Seven of these were mould growths comprising species of 

 Cladosporium and Epicoccum. Eleven were yeasts, while the fourteen^ 

 bacterial colonies were Sarcina aurentiaca, Micrococcus rosens, a sporing 

 bacillus and Cladothrix sp. 



E. Glucose agar plate exposed for five minutes to the atmosphere in the 

 storeroom for empty boxes, butter-paper, salt, &c. The total count of 

 micro-organisms was thirty-four. Twenty -one of these were mould growths 

 comprising species of : Cladosporium, Alternaria, Penicillium and Epicoccum. 

 Three colonies of yeast were counted, while amongst the bacterial colonies 

 were Staphlococcus albus, Sarcina and Cladothrix sp. 



F. Ordinary agar plate exposed five minutes to the atmosphere in -the 

 cold room. The total count of micro-organisms was forty-eight. Thirty- 

 eight of ' these were mould growths comprising species of Penicillium, 

 Alternaria and Cladosporium. Two colonies of yeast appeared, one 

 Cladothrix sp., three Bact. subtilis, and three yellowish slimy colonies of 

 a gram-positive bacterium which rapidly liquefies gelatin. 



Summary of Results. The large numbers of undesirable organisms found 

 in the cream before pasteurising suggests unsatisfactory and unclean con- 

 ditions on at least some of the dairy farms. Pasteurisation effectively 

 destroyed all vegetative forms of undesirable organisms. The holding of 

 the pasteurised cream in open vats, exposed to the air and dust of an old 

 factory with insanitary surroundings is disastrous, seeing that from the 

 plates over half a milkon per c.c. of undesirable organisms were added in 

 twenty hours. These would be sure to exert their deteriorating influence 

 upon the good-keeping qualities of the butter. 



