PART III 
MANUFACTURE OF UNSWEETENED CON- 
DENSED MILK 
EVAPORATED MILK 
Crarter VITT. 
DEFINITION. 
There are three kinds of unsweetened condensed milk on 
the market, namely, evaporated milk, formerly called evaporated 
cream, plain condensed bulk milk and concentrated milk. 
Evaporated milk is cow’s milk condensed in vacuo at the 
ratio of about two to two and one-half parts of fresh milk to one 
part of condensed milk. It is of the consistency of thin cream 
and reaches the market in hermetically sealed cans varying in 
size from eight ounces to one gallon. Evaporated milk is pre- 
served by sterilization in steam under pressure. \When properly 
made, it will keep indefinitely, but is best when fresh. 
QUALITY OF FRESH MILK. 
In the manufacture of evaporated milk the physiological 
normality and the chernical purity and sweetness of the fresh 
milk are factors even more important than in the case of sweet- 
ened condensed milk. A uniformly satisfactory and marketable 
product cannot be manufactured. unless the milk is normal and 
pure in every respect. The reason for this largely les in the 
fact, that defects the fresh milk may have, are greatly magnified 
and intensified by the high sterilizing temperature to which the 
evaporated milk is subjected. While, from the biological point 
of view, contaminations of this milk are largely rendered harm- 
less by sterilization, defective fresh milk cannot be made into 
a marketable product, because such milk usually does not survive 
the process. 
It should be understood that any condition or factor that, 
in the slightest degree, increases the tendency or ability of the 
