284 



MANUFACTURE: OF MILK POWDER 



as may adhere to the grinding surface. Baffle boards or dash 

 boards are provided to receive such of the milk, as may splash 

 from the cone. 



The patent claim covers the drying- of the milk by feeding 

 it to a continuously moving, heated surface, where it is permitted 

 to form a comparatively thin layer, heating it to evaporate the 

 water, and simultaneously subjecting it to a kneading, which 

 gradually changes to a grinding action, as the milk solidifies, 

 and forms a powder. 



The temperature of the heating surface is recommended to 

 be that of boiling water, but may be between 212 degrees F. and 

 270 degrees F. The milk enters the hopper without preheating 

 and without other treatment. 4 . 



The Passburg Process. This process was invented and 



Fig-. 95. The Passburg milk drier 



patented by Emil Passburg of Berlin, Germany, U. S. patent 

 No. 726,742, April 28, 1903. This film dryer operates under 

 reduced pressure. It consists of an outer casing (A) in which 

 revolves one steam heated, metal drum (T), an automatic milk 



