SWEETENED CONDENSED MILK CONDENSING 



75 



pan atomizing- into a dense spray, which is partly drawn over 

 into the condenser, causing loss of milk. 



The body of the pan also usually carries, near its lower 

 portion, a sampling cup, or striking cup, which facilitates the 

 sampling and testing for density, of the contents of the pan 

 while the pan is in operation. 



A suitable, permanent covering should be provided for the 

 body of the pan for insulation against heat radiation. This will 

 not only economize fuel and speed evaporation, but it will also 



assist in keeping the pan room 



reasonably cool. 



The Dome rests on top of 

 the body of the pan. It is equip- 

 ped with a manhole, manhole 

 cover, thermometer, vacuum 

 gauge, sight glasses, lights, 

 blow-down valve or 

 vacuum breaker. The 

 manhole measures 

 about fourteen to 



Fig. 21. Vacuum gauge 



Courtesy of Arthur Harris & Co. 



eighteen inches in di- 



ameter. It is closed 

 by a solid brass cover 



with a well-fitting, ground surface flange. The cover 

 carries a five-inch spy-glass or sight-glass through 

 which the operator watches the boiling milk in the 

 pan. The stem of the thermometer is enclosed in a 

 brass casing and reaches to near the bottom of the 

 pan. Some processors prefer a short thermometer 

 which registers the temperature of the vapors instead 

 of that of the milk. As both, the milk and the vapors 

 are subjected to the same pressure, their respective 

 temperatures are the same. The vacuum gauge con- 

 nects with the interior of the pan, and indicates the 

 number of inches of vacuum. A mercury column may 

 be used in the place of the vacuum gauge. In the 

 rear of the dome there are two sight glasses. Through 



. . f , j t. Courtesy of 



these the interior of the pan is illuminated by means c. E. Rogers 



Fig. 22 



Mercury 

 Column 



