CHAPTEK VI 



The Bacteria of Milk 



ALTHOUGH the functions performed by micro- 

 organisms in the dairy have only comparatively 

 recently come to be recognised, it has long been 

 realised, by the help of experience, that a very 

 necessary condition of successful dairying is cleanliness. 

 By working in a cleanly fashion in the dairy, con- 

 tamination with bacteria is avoided to a large extent ; 

 for the only dangerous constituents of dirt are these 

 minute living organisms dead dust is a harmless 

 enough article. 



The changes which micro-organisms may effect in 

 milk have been again and again exemplified by the 

 mysterious development of strange milk "faults," 

 already referred to in the preceding Chapter. Among 

 these may be mentioned such as manifest themselves 

 by the milk becoming ropy, stringy, or viscous ; by 

 its assuming a blue, red, yellow, etc., colour, or, at 

 least, the development of coloured patches in it, a 



