EVAPORATKD MILK STERILIZING 



121 



the sterilizer and a water exhaust. The sterilizer carries on its 

 exterior a steam gauge, a vacuum gauge, a water gauge, a blow- 

 off valve and a high-temperature thermometer (registering to 

 about 280 degrees F.). In some makes of sterilizers the interior 

 frame-work does not revolve on its axis, but moves back and 



forth by means 

 of a direct-act- 

 ing, steam- 

 driven piston, 

 attached to the 

 back end of the 

 sterilizer. The 

 purpose of 

 keeping the 

 cans in motion 

 while heat is 

 applied, is to 

 heat the coti- 

 tents rapidly 

 and unifonn|ly, 

 and to prevent 

 the evaporated 

 milk from bak- 

 ing onto the 

 sides of the 

 cans. A still 



other form of sterilizer is the continuous sterilizer in which the 

 unsterilized cans pass into and the sterilized cans escape from 

 the heating chamber in continuous procession. 



Loading the Batch-Sterilizer. The sealed tin cans are placed 

 in heavy iron trays, usually holding twenty-four 16-ounce cans or 

 six 1-gallon cans. The loaded trays are slid and locked into the 

 framework in the interior of the sterilizer. The sterilizer is closed 

 with heavy iron doors and the frameAvork is put in motion. In 

 some makes of sterilizers the interior consists of a large per- 

 forated iron box revolving on its axis. In this case the cans are 

 simply piled into this box; no trays being used. 



Uniform Distribution of Heat. Where no water is used in 

 the sterilizer during the sterilizing process, it is important that 



Fig. 46. Sterilizer for evaporated milk 

 Courtesy of The Engineering Company 



