70 MILK PRODUCTS 



mercial condensed milks usually represent whole 

 milk concentrated to about one-third or two- 

 sevenths of its original volume. A small amount 

 of invert-sugar may be present. The most com- 

 mon defect in condensed milks is deficiency 

 in fat, due to preparation from closely skimmed 

 milks. Preservatives (other than sucrose) and 

 coloriiig-matters are rarely used, nor is it likely 

 that foreign fats will be present. 



The fat of unsweetened condensed milk can be 

 readily determined by theL-B method (page i8). 



In a recent publication, Bigelow andFitzgerald 

 give the following detailed description of the 

 application of the Leflmann and Beam method 

 to the examination of unsweetened condensed 

 milk: 



Weigh 9 grams of evaporated milk into an 

 8% Babcock milk bottle. Add lo c.c. of water. 

 Thoroughly mix by shaking and add 3 c.c. of a 

 mixture of equal parts of amyl alcohol and con- 

 centrated hydrochloric acid. Shake thoroughly 

 and add 10 c.c. of concentrated sulfuric acid 

 (1.84 sp. gr.) in three or four portions, mixing 

 after each addition. If too much heat develops 

 the bottle may be cooled somewhat in water 

 during the addition of the acid. 



Fill the bottle to near the base of the neck with 

 a hot fresh mixture of equal parts of sulfuric 

 acid and water. Thoroughly mix the contents 



