266 DAIRY TECHNOLOGY 



advertised " plasmon " is made in this manner. The 

 process was not economical as some of the milk nutrients 

 (sugar and albumen) were lost in the whey. This sub- 

 stance (plasmon) does not contain all of the elements 

 of milk, and therefore could not serve as a substitute for 

 milk. 



Milk powder became of commercial importance when 

 the Just-Hatmaker machine and process of drying came 

 into use. The patent for this process is dated May 23, 

 1902. The desiccating machine consists of two large 

 revolving polished rollers or cylinders placed parallel in 

 a frame. The rollers are about sixty inches in length 

 and twenty-eight inches in diameter. They revolve in 

 opposite directions at about six revolutions per minute. 

 Steam is introduced through the end of the spindle and 

 a pressure of 40 pounds is maintained. This insures a 

 constant temperature of 285° F. The condensed steam 

 is removed at the other end at the corresponding place. 



The two cylinders are about one eighth of an inch apart. 

 When the milk falls and spreads in thin sheets on these 

 revolving hot cylinders, it dries almost instantaneously. 

 The residue remains on the cylinders and is scraped off in 

 a powder-like consistency by means of scrapers attached 

 to the machine. The powder is now passed through a 

 fine sieve and is then ready for packing. 



Drs. George Doellner, Buttler and J. Maggo have all 

 patented homogenization of the milk previous to dry- 

 ing. It is claimed that this improves the keeping prop- 

 erty. The process reduces the size of the fat globules to 

 such an extent that decomposition proceeds very slowly. 

 This latter, however, is by no means a well-estabHshed fact. 



Dr. Eckenberg of Sweden has invented an ingenious 

 system of milk drying at a low temperature and in vacuum. 



