112 APPLIED PHYSIOLOGY 



or of too poor quality to be sold as good milk. While such milk may 

 not be injurious, yet it is a fraud to sell it at the price of good milk. 

 Skim milk is bluish in color from the loss of its cream. To make it 

 the color of new milk, burnt sugar is often added, and it is then some- 

 times sold as new milk. It is very apt to become sour from its being 

 kept for some days. 



164. Condensed milk. Large quantities of milk are boiled 

 until its water is evaporated and the milk is like thin jelly. This is 

 condensed milk. In order to keep it, sugar is added. Condensed milk 

 contains all the nourishment of new milk, with some sugar added. It 

 can safely be used in place of new milk for all cooking purposes. It is 

 too sweet to be used as a drink, but babies take it readily. Still it is 

 undesirable as a baby food, for it contains too much sugar. 



165. Imitation cheese and butter. Cheese made from skim 

 milk contains but little fat. It easily ferments and becomes dry, so 

 that it is very indigestible. There is an imitation of butter made from 

 beef fat, called oleomargarine. It scarcely can be distinguished from 

 real butter. Butterine is another imitation of butter made from beef 

 fat and butter. The manufacture and sale of both kinds of imitation 

 butter are permitted so long as the products are sold under their right 

 names. 



166. Eggs. Hens' eggs consist of 



Water 70 per cent 



Albumin 15 " 



Fat 14 



Mineral matter i " 



Since they contain no starch or sugar, they are not a 

 complete food for man, although a perfect chicken may be 

 formed out of the egg, as the hen furnishes heat. The 

 white of egg is almost pure albumin dissolved in water. 

 The yolk is a mixture of albumin, fat, and water. Both 

 the albumin and fat of eggs are digested with little expend- 

 iture of time and energy, and develop a large amount of 

 heat and energy in their oxidation. They do not easily 

 ferment in the stomach and intestine, and only about one 



