FOODS AND NUTRITION 



389 



drop, until a faint blue color appears, but no precipitate. 

 Now add the solution to be tested. A violet color indicates 

 protein. 



Beans 



Eggs 



Milk 



Bread 



Cheese 



Sceak 



Rolled Oats 



Potatoes 



FIG. 347. Foods Containing Equal Amounts of Proteins. 



Carbohydrates. --This class of foods is made up of 

 the starches, sugars, and glucoses, and enters largely 

 into the composition of foods of vegetable origin. The 

 carbohydrates contain carbon, hydrogen, and oxygen, 



FIG. 348. Sugar and Starch are Foods that Produce Power and Heat. 



as the name indicates. They are essentially energy- 

 producing foods or fuel foods (Figure 348). 



Green plants make all of the carbohydrates which we 

 use as food, except milk sugar. In the presence of sun- 



