60 SWEETENED CONDENSED Mirt,.K—H&a tine 
Solution of Sucrose.—It is very essential that all the cane 
sugar which is added to the mill be completely dissolved, in 
order to lessen the tendency of the sugar to form large crystals 
in the finished product. Undissolved sugar crystals in condensed 
milk act in a physical way much as bacteria in fluid milk do in a 
bacteriological way. “Chey multiply rapidly, and such condensed 
milk usually precipitates its sugar before the product reaches 
the market. The presence of excessively large sugar crystals 
makes the product gritty and causes the formation of a sediment 
in the bottom of the cans; this is objectionable to the consumers. 
When the milk is heated to-the proper temperature before con- 
densing, the solution of the cane sugar is facilitated and the 
tendency toward prittiness is minimized. 
Prevention of Burning Milk on Heating Surface—lIf cold 
mill comes in contact with a steam-heated surface and is not agi- 
tated vigorously, it bakes or burns onto this heatine surface. The 
mille in the vacuum pan is heated or kept hot by means of the 
steam jacket and coils. ‘Uhese radiators are charged with steam 
under pressure and consequently give off a high degree of heat. 
If cold milk is drawn into the vacuum pan, the milk remains 
calm for a considerable length of time. During this time it is 
bound to bake or burn on the heating surface, giving the product 
a burnt flavor, causing it to contain brown specks and retarding 
the process of evaporation. Jf the milk is hot when it enters the 
pan, the reduced pressure in the pan causes it to boil violently at 
once, avoiding all danger of sticking to and burning on the heat- 
ing surface and making possible maximum rapidity of evapora- 
tion. 
Temperature. In most factories the milk is heated to from 
180 degrees I. to 200 degrees I’. his temperature is sufficient 
to accomplish the three purposes. [leating the milk to the 
boiling point tends to give it a rather pronounced cooked flavor, 
which is objectionable. Tlowever, in the case of danger of con- 
tamination of the milk with resistant types of undesirable bac- 
teria, if may become necessary to practice boiling the milk, 
Manner of Heating. —'Thorouch, efficient and rapid heating 
of large volumes of milk to temperatures near the boiling point 
ig a problem that requires careful consideration, ‘The tendency 
