ADULTERATIONS OF CONDENSED MILK 271 
Evaporated milk may also show a metallic flavor as the result 
of chemical action of the acid in the milk on the can. This occurs 
usually only upon prolonged storage. Very old evaporated milk 
is very prone to have a metallic flavor from this source and 
particularly when stored at a rather high temperature. This can 
best be avoided by endeavoring to move the goods sufficiently 
rapidly to limit the age of the milk to a reasonable period of time 
and by avoiding high storage temperatures. 
Cans, in the manufacture and sealing of which an acid Hux 
is used, are prone to give the contents a puckery, metallic flavor, 
due to the zine chloride and hydrochloric acid present. This can 
be avoided by using cans only in the manufacture of which a 
non-acid flux, such as gasoline-resin flux, is used, and by using 
a non-acid flux for sealing the filled cans. 
CHAPTER XXIV. 
ADULTERATIONS OF CONDENSED MILK. 
It is the sense of the Federal Pure Food Act that the addition 
to condensed milk of any substance except sucrose, and the 
abstraction of any substance from milk except water, is an 
adulteration. 
Skimming.—Condensed milk made from partly or wholly 
skimmed milk must be labeled and sold as condensed skimmed 
milk in order to comply with the Pure Food regulations. How- 
ever, it is possible for condenseries receiving fresh milk, rich 
in butter fat, to skim a part of that milk and have their product 
still conform with the food standards. 
Skimmed sweetened condensed milk can readily be detected 
by its whitish color, while condensed whole milk has normally 
a rich yellow color. When diluted, to the consistency of ordi- 
nary milk, skimmed condensed milk, both the sweetened and the 
unsweetened, foams very profusely when shaken, while diluted 
condensed whole milk behaves similar to ordinary whole milk.! 
Addition of Artificial Fats—JIn order to lower the cost of 
manufacture, attempts have occasionally been made to skim the 
1For chemical tests of butter fat in condensed milk see Chapters XXXI 
and XXXII. 
