94 



Condensed Milk and Milk Powder 



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-acting, 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 contents rapidly and uniformly, and to 

 prevent the evaporated mi'lk from baking onto the sides of the cans. 



Loading the Sterilizer. — The sealed tin cans are placed in heavy 

 iron trays, usually holding twenty-four 16-ounce cans or six i-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 framework is put in motion. In some makes of 

 sterilizers the interior consists of a large perforated iron box re- 

 volving 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 there be 

 a free air space between every two layers of cans, so as to allow the 



steam to circulate 



freely and to come in 



direct contact with 



every can. When the 



cans are piled into the 



sterilizer six to twelve 



layers deep without 



any free air space be- 

 tween layers, the cans 



in the center do not 



receive as much heat 



as those at the sides, 



ends, top and bottom. 



This causes irregular 



heating and imperfect 



sterilization. 



A satisfactory means of insuring even distribution of heat is to 

 fill, the sterilizer about one-third full of water, so that, when the ster- 

 ilizer is in operation, the cans pass through this water, with each 

 revolution of the frame work. Water distributes the heat uniformly 



Fig. 42. Time control gauge 



Courtesy of 

 C. J. Tagliabue Mfg\ Co. 



Fig. 43. Diaphragm 



Courtesy of 

 C. J. Tagliabue Mfg. Co. 



