SWEETENED CONDENSED MILK ADDITION OF SUGAR 57 



steam to be "wet." It is estimated that the amount of extraneous 

 water thus added to the milk increases the bulk of the milk by about 

 one-sixth of its original volume. The steam is often associated 

 with impurities, such as cylinder oil from the engine, boiler com- 

 pounds used in the boilers, scales from the inside of the pipes, etc. 

 These various impurities cannot possibly improve, but may seriously 

 injure the quality of the milk. It is quite probable, also, that the 

 direct contact of live steam with milk has no beneficial effect on its 

 ingredients. It is generally conceded by those who have given this 

 matter careful thought, that the turning of steam direct into the 



Fig. 12. Steam rosette for heating milk 

 Courtesy of Arthur Harris & Co. 



milk shortens the life of the product and causes it to develop a stale 

 flavor, which may degenerate into an oily flavor. The same defect 

 is noted also when cream is heated by turning steam into it. The 

 prolonged exposure of the milk to the condensing process, as the 

 result of the addition to the milk of considerable quantities of con- 

 densed steam, further may be injurious to the milk. 



Any method of heating that does not require direct contact of 

 the steam with the milk is preferable, provided that it makes possible 

 thorough heating to the required temperature without burning the 

 milk. Practically all of the other methods above referred to accom- 

 plish this when properly applied. 



ADDITION OF SUGAR 



Considerable quantities of sucrose are added to the condensed 

 milk for the purpose of preserving it. 



Kinds of Sugar. In order to convey to the milk preservative 

 properties, that kind of sugar must be used which does not readily 



