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 contains 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 bac- 

 teria, yeast, molds and enzymes that cause it to undergo un- 

 desirable fermentations which, if allowed to pass into the con- 

 densed milk, may tend to shorten the life and impair the whole- 

 someness and marketable properties of the latter. 



