148 MODERN DAIRY PRACTICE. 



contained in it by means of a separator, and is then evap- 

 orated in a vacuum-pan till it contains 37$ of dry substance. 

 The condensed milk is filled into tin cans by a special 

 measuring and filling apparatus, and these are then sol- 

 dered and heated in the sterilizer under steam-pressure. 

 This method seems to possess many advantages over the 

 first-mentioned one. The condensed milk is free from 

 milk dirt, has no disagreeable sweet taste, and contains 

 always the same quantities of water; it has therefore 

 always the same consistency. 



As already stated, the condensed milk has not found 

 application on the milk markets proper, although its keep- 

 ing qualities have been all that could be wished for. Its 

 consistency is too different from that of ordinary milk, and 

 its price has been too high. The effort has therefore been 

 made to preserve milk by sterilization without changing 

 its physical properties. This sterilization of the milk may 

 be effected in two different ways : first, by filtration, and 

 second, by heating.*' 



Sterilization by Filtration. Different kinds of mate- 



* I pass by the method proposed by the Frenchman Guerin to keep 

 milk in a frozen condition. By this method the bacteria are certainly 

 prevented from starting fermentations, but the method is not prac- 

 ticable, since the milk undergoes certain changes in freezing which 

 decrease its application. [Notices occasionally appear in the agricul- 

 tural press concerning the sale of frozen milk in foreign countries. 

 In the Danish Landmandsblade (vol. 37, p. 305) the following 

 item was thus given, the correctness of which I am not in position 

 either to confirm or deny : "Frozen milk is an article of food of late 

 years introduced to an appreciable extent in France and Siberia. 

 The frozen milk is comparatively easily transported, will keep for a 

 long time, and when melted is said to be as palatable as fresh new 

 milk." W.] 



