Testing Milk for Taints. 621 



the action of a particular group of bacilli of the colon order which 

 get into the milk through the medium of dirt. Fig. 5 is from the 

 same milk as Fig. 8 but with the addition of a little whey from a 

 dirty tank. The effect of this was astounding and the curd came 

 out just like a sponge, which on being squeezed and freed again, 

 relaxed and expanded. This test was conducted to prove to the 

 suppliers the effect of carrying milk in improperly washed cans in 

 which whey had been previously taken home. By providing separate 

 vessels for the conveyance of the whey and then thoroughly ^washing- 

 and sterilizing the cans by steaming them at the factory this trouble 

 was overcome. Fig. G illustrates a cheese made from milk highly 

 contaminated by these gas producing organisms, the smooth, round, 

 shiny holes being very distinct. The same effect will be produced 

 by taking a sample of pure milk and adding a little cow dimg, when 

 the curd obtained will be full of pinholes. Until this taint is elim- 

 inated from the milk a good flavoured cheese cannot be made. 



