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 flux 

 is used, are prone to give the contents a puckery, metallic flavor, 

 due to the zinc 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 XXTV. 

 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. 1 



Addition of Artificial Fats. In order to lower the cost of 

 manufacture, attempts have occasionally been made to skim the 



1 For chemical tests of butter fat in condensed milk see Chapters XXXI 

 and XXXII. 



