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rod like bacteria. In fact, nearly twenty species of bacteria 

 have been found that will produce ropy milk. In some cases 

 the ropiness appears to be due to " the swollen outer cell 

 membrane of the bacteria themselves; in others it is due to 

 different substances formed from the proteids in the milk, 

 and, occasionally, the milk sugar." (Russell.) 



Ropy milk bacteria can be eradicated from the dairy by 

 cleanliness, disinfection, and possibly by sterilizing. In Hol- 

 land slimy or ropy fermentation of milk is desired in the 

 manufacture of Edam cheese. The Norwegians make a pop- 

 ular drink by producing a slimy change in milk ; the milk is 

 infected by introducing the leaves of the common butterwort. 



Chroniogenic or Color-Producing germs are sometimes 

 found in milk. Red Milk maybe due to the presence of blood 

 from an injured or diseased udder. In such cases the milk 

 will appear red at the time of milking. Milk may appear red 

 when one or more of pigment-producing germs grow in it. 

 The most common germ that produces this red tinged milk is 

 called the bacillus prodigiosus. This germ is reported to be 

 rarely, if ever, found in America. However, in October, 1897, 

 the writer isolated it from a rotten cotton boll. Another red 

 milk germ is the bacillus lactis erythrogenes (Hueppe). Sar- 

 cina rosea is also said to produce a red color in milk. These 

 red milk germs not only develop a red pigment in milk, but 

 also produce coagulation of the casein. The bacillvs jjrodigi- 

 osus may form trimethylrain, which gives milk a herring like 

 smell and taste. Cleanliness and disinfection are the means 

 of getting rid of the red milk germs. 



Blue Milk may be a result of the growth of certain geims 

 in milk. This must not be confounded with what is com- 

 monly known as blue milk, which is blue-tinted, poor milk, 

 or milk that appears blue after the cream has been removed. 

 The blue pigment, developed by the baciUus cyanogenns, will 

 appear, in from one to three days after infection or inoculation, 

 as isolated, bluish colored patches on the surface of the milk ; 

 after a time the entire surface of the milk may become coated 

 with a blue film. The action of this germ on the milk is 

 unknown. Butter made from infected cream will not 



