PART II. 



MANUFACTURE OF SWEETENED 

 CONDENSED MILK 



Chapter IV. 

 DEFINITION 



Sweetened condensed milk is cow's milk, condensed at the ratio 

 of 2^ to 2^ parts of fresh milk to 1 part condensed milk. It con- 

 tains considerable quantities of sucrose, usually about 40 per cent, 

 to preserve it. It is of semi-fluid consistency and reaches the market 

 in hermetically sealed tin cans, varying in size from eight ounces to 

 one gallon, and in barrels similar to glucose barrels, holding from 

 three hundred to seven hundred pounds of condensed milk. When 

 made properly, sweetened condensed milk will keep for many 

 months, but is best when fresh. 



HEATING 



Purpose. — The first step in the process is to heat the milk to 

 near the boiling point. There are three chief reasons for which the 

 milk is heated, namely, to destroy most of the bacteria, yeast, molds 

 and other organized and unorganized ferments, to facilitate the 

 solution of the sucrose, and to prevent the milk from burning on to 

 the heating surface in the vacuum pan. 



Destruction of Ferments. — When the fresh milk arrives at 

 the factory it contains micro-organisms in varying numbers and of 

 different species. In some cases disease-producing bacteria may be 

 present, rendering the milk dangerous to the health and life of the 

 consumer, were it not heated to temperatures high enough to destroy 

 these germs. Again, milk may contain bacteria, yeast, molds and 

 enzymes that cause it to undergo undesirable fermentations which, 

 if allowed to pass into the condensed milk, may tend to shorten the 

 life and impair the wholesomeness and marketable properties of 

 the latter. 



Solution op Sucrose. — It is very essential that all the cane 

 sugar which is added to the milk be completely dissolved, in order 



