Concentrated Milk 319 
skimmed milk. The fresh milk is heated to about 
160° F. and condensed in vacuo at 130° F. to 150° F. 
The ratio of concentration is 3 to 4:1 (3 to 4 parts 
of fresh milk are condensed to one part of condensed 
milk). Before it leaves the vacuum pan, it is super- 
heated by live steam to swell or thicken it. It is sold 
in 10-gallon milk cans. It has the consistency of 
very thick cream, and has a specific gravity of about 
1.09. This product is largely sold to ice cream manu- 
facturers, and limited quantities of it are retailed in 
milk bottles to the direct consumer. It sells at from 
25 to 75 cents per gallon. 2 
Plain. condensed bulk milk is not sterile. Its keep- 
ing quality is similar to that of a good grade of pas- 
teurized milk. 
Concentrated milk.—Concentrated milk is made 
from fresh milk. Before condensing, the cream is 
removed, and the skim milk is condensed at 140° F. 
by blowing hot air through the milk. When the con- 
centration is completed, the cream is returned to the 
condensed product. The ratio of concentration is 
about 3:1 (about 3 parts of milk are condensed to 1 
part of concentrated milk). This product is used for 
direct consumption. It differs from plain condensed 
bulk milk only in that it has not been exposed to so 
high temperatures during the process. 
Concentrated milk is not sterile. It keeps about 
as long as a good grade of pasteurized milk. Its 
manufacture is very limited. 
The chief essential in the successful manufacture 
of all condensed milks is a good quality of fresh milk. 
