136 MODERN DAIRY PRACTICE. 



in 1888 concerning the behavior of the lactic acid bacteria 

 after repeated inoculations in sugar-free gelatine.* 



Putrefactive bacteria appearing in the ice also showed 

 a considerably diminished peptonizing power. By inocu- 

 lating for a long time slightly virulent bacteria of this kind 

 successively on new fermentable mediums I have again 

 been able to awaken their fermentative power and gradually 

 return the normal virulence to the organisms. 



Uses of Purified Water in Factories. In some cases boiled 

 water had better be applied in creamery and dairy work, and 

 in other cases recently melted ice-water had better be ap- 

 plied, as will be apparent from the following examples : 



The last rinsing of milk vessels ought always to be 

 made with boiling-hot water. By this we gain both that 

 the vessel dries more rapidly and that the water in evapo- 

 rating does not leave behind living bacteria. The same is 

 true in rinsing the churn, butter-worker, and all other 

 utensils coming in direct contact with milk, cream, or 

 butter. 



Before the cream is poured into the churn the walls of 

 the latter ought to be given the temperature proper for 

 churning by the application of recently-melted ice-water. 

 When the butter, as is often the case, especially in making 

 " Paris butter," is to be washed in the churn we ought 

 generally to use water of comparatively low temperature, 

 according to the experience gained at several creameries. 

 40 F. (4 C.) is considered the best temperature at many 

 places. Water containing pieces of ice is well adapted 

 to this purpose; the pieces of ice ought not, of course, to 

 go into the churn. 



* " See Saprofyta mikro-orga'nismer i komjolk," pp. 36-42. 



