56 DAIRY ANALYSIS 



a mineral acid is added to milk, and this is usually seen 

 in the G-erber test. Other artificial colours are practically 

 never used. 



A pink colour is generally due to blood ; to detect 



FIG. 28. High-speed Centrifuge. 



this the milk isjwarmed to 50 C., and separated in a 

 high-speed centrifuge (Fig. 28) ; a bright red deposit 

 at the bottom of the tube may be taken as blood ; the 

 microscopic appearance of the corpuscles is given in 

 Fig. 29. 



