MANUFACTURE OF MII,K POWDER 



283 



The Gathmann Process. This process and equipment was 

 invented and patented by Louis Gathmann of Washington, 

 D. C., U. S. patent No. 834,516, October 30, 1906. 



In this process, similar as in the Just process, the milk is 

 dried in the form of a film on a revolving, steam-heated drum, 

 under atmospheric pressure. In this case, however, only one 

 drum is used, the drum (A) is cone-shape instead of cylindrical 

 and its surface is spirally grooved or corrugated (a) and the 

 adjacent surface against which the cone revolves is also similarly 

 corrugated but the spiral grooves (b 1 ) running in the opposite 



Fig*. 94. The Gathmauu milk drier 



direction from those on the cone, as is common in grinding- 

 mills. Hence when the cone revolves the drying milk is kneaded 

 and ground between the two surfaces and is gradually carried 

 or pushed by the corrugated surface of the revolving cone to 

 the smaller, or discharge end of the machine. 



The adjacent corrugated surface against which the surface 

 of the cone grinds, and which incases the lower half of the surface 

 of the cone, is steam jacketed (b 2 ), so that the milk is between 

 two heated surfaces. 



A hopper (D) regulates and feeds the flow of the milk to 

 the cone at its larger end and a brush (G) located near the 

 smaller end of the cone removes such parts of the dried milk 



