SWEETENED CONDENSED MILK ADDITION OF SUGAR 61 



the presence of excessive amounts of cane sugar in condensed milk 

 tends to reduce its digestibility and its wholesomeness as a food. 

 Again, while normal milk is a well-balanced food in itself, the pres- 

 ence of large amounts of cane sugar in it causes this equilibrium to 

 be disturbed, the condensed milk being excessively rich in carbo- 

 hydrates and relatively poor in proteids. These facts are specially 

 significant where condensed milk is used for infant feeding and by 

 persons with weak digestion. 



On the other hand, sweetened condensed milk depends for its 

 preservation on the sucrose. This class of condensed milk is not 

 sterile and is prevented from rapid deterioration by the preservative 

 action of the sucrose only. Therefore, the smaller the amount of 

 sucrose it contains, the greater the danger from the activity of fer- 

 ments and the less its keeping quality. 



The relative prices of cane sugar and of fresh milk also govern 

 the amount of cane sugar used in many factories. In summer, milk 

 prices are low and sugar prices are high, while in winter the rela- 

 tive prices are reversed. Hence there is a tendency on the part of 

 the manufacturer to use less sugar in summer than in winter. 



Again, the amount of cane sugar used varies according to the 

 kind of market for which the condensed milk is intended. Milk put 

 on the market in hermetically sealed cans is generally exposed to 

 more unfavorable conditions and is older by the time it reaches the 

 consumer than milk sold in barrels. It is customary to use about 

 sixteen pounds of cane sugar for every one hundred pounds of fresh 

 milk for canned goods, and about twelve to fourteen pounds of cane 

 sugar for barrel goods. 



Finally, there is a strong tendency in some localities for sweet- 

 ened condensed milk made in May and June, to thicken rapidly 

 and become cheesy with age. This can easily be prevented by the 

 use of more cane sugar in the milk manufactured during these 

 months. (See Chapter XXIII on "Condensed Milk Defects.") 



Mixing the Sugar. The sugar is added to the hot milk before 

 the latter enters the vacuum pan. In some factories a separate tank 

 is provided for this purpose. Small portions of the hot milk are 

 allowed to flow into this tank. To these the sugar is added. This 

 tank is called the sugar well. It is usually equipped with a mechan- 



