82 SWEETENED CONDENSED M1LK—CONDENSING 
value, as 1s the case in condensing milk, the barometric and wet- 
vacuum condensers are best suited; if properly constructed, their 
operation utilizes the cooling water most economically. 
Care of the Condenser.—In the operation of the spray and 
jet condenser, special attention should be paid to the condition 
of the spray pipe, or spray plate. Especially, when the water 
used contains much organic matter, as is the case with water 
from a creek, pond or lake, there is a tendency of the spray equip- 
ment becoming filled and coated with slimy organic matter, 
causing the perforations to clog. This renders the distribution 
of the spray irregular and the control of the pan difficult. It 
causes great waste of water because much of the water is dis- 
charged from the condenser and lost without coming into direct 
contact with the vapors. ‘The water is, therefore, not utilized 
economically and the difference between the temperature of the 
vapors and the discharge of the condenser is excessive. In order 
to avoid this the condenser should be cleaned out thoroughly at 
least once a week, or oftener if necessary, to keep the pores of 
the spray pipe or plate free from obstructions. It is advisable to 
install condensers equipped with a manhole, properly located, 
otherwise access to the spraying arrangement is not sufficiently 
convenient to insure frequent inspection and thorough cleaning 
by the average operator. 
The Expansion Tank, Catch-All, or Milk Trap.—This is a 
tank frequently installed between 
the dome of the pan and the con- 
denser. Its purpose is to collect and 
reclaim any milk that may be carried 
over from the pan and to prevent 
its escape and loss through the con- 
denser. 
If the pipe through which the 
milk enters the pan is turned down 
and its end is carried to near the 
bottom of the pan, so as to avoid 
the formation of excessive milk 
spray, if the pan is operated care- 
fully and if the milk is kept at a Fig. 29. eee with milk 
reasonably low level, there is very  Gourtesy of Arthur Harris & Co 
