Foods and Cooking. 143 



salted codfish is a nourishing and economical food. Fish 

 is not an especially valuable brain food, as commonly 

 believed. 



Eggs. Eggs contain considerable proteid, but their value 

 as food has been overrated. The yolk has a large amount 

 of fat. Although the egg has all the material needed to 

 form a chick, it is not a perfect food for man. 



Milk. Milk, as we have seen, is an ideal food, in that 

 it contains all the kinds of foodstuffs, and in the right pro- 

 portion for the young mammal. But the proportions are 

 not right for the adult. An adult would need four quarts 

 and a half daily, and then he would not get enough carbo- 

 hydrates (represented in milk by the sugar). The oily 

 material in milk is in the form of minute globules, which 

 can easily be seen under the microscope. Each of these 

 oil droplets is surrounded by a thin envelope of albumen, 

 by means of which it is enabled to remain suspended for 

 some time instead of rising quickly to the surface. Such a 

 mixture of oil in a liquid is called an emulsion. When 

 cream is churned the albuminous covering is removed and 

 the butter " gathers." 



Cheese. Cheese is very rich in proteid, much more so 

 than lean meat. Yet, as it is hard to digest, we do not use 

 it much as food; we regard it more as a luxury, while in 

 many parts of Europe it is largely used as food, taking the 

 place of meat. It is a cheap food, and might well be used 

 more extensively, especially by laboring men. When taken 

 with milk, it is said to be more readily digested. 



Vegetable Proteids. Peas and beans (dried) contain as 

 much proteid (legumin) as meat, and all the cereals contain 

 some proteid (gluten). 



