ILLINOIS STATE D URYMEN'S ASSOCIATION. q^ 



We may consider the white of an egg, or the cheese part of miik the 

 best examples of protein. The gluten of flour, the lean part of m^eat are 

 also protein sub&tances. Oil meal, gluten meal, peas, bran, and mid- 

 dlings are all rich in protein. Oats contain a fair quantity of protein, 

 while Indian corn is relatively poor in that constituent. The stems of 

 leguminous plants, such as clover, alfalfa, cow pease, the common field 

 peas, etc., are quite rich in protein when cured into hay, while oat straw, 

 corn stover (shock corn from which the ears have been husked) are com- 

 paratively poor in protein. Instead of saying "protein substances," we 

 frequently use the term "nitrogenous substances," to characterize this 

 group of materials for the reason that they all contain nitrogen, an 

 element not found in the group o which I shall next speak. 



The higest use of protein or the nitrogen substances is tO' build up the 

 muscles of the body and to replace their waste. The protein substances 

 also constitute the organic part of the bones, most of the hide, hair, horns^ 

 nerves, and blood of the body. The word "protein" means, first in im- 

 portance, and we will readily agr ee that it was. well named. 



In its secondary use protein is broken down in the body and furnisher 

 heat and energy, or it may be coi! verted into fat foT storing in the tissues 

 against time of need. 



CARBOHYDRATES. 



Here is a long word, but let us learn to use it. Sugar is a pure, crys- 

 talized carbohydrate, and I am sure no one need ever forget the meaning, 

 of the word hereafter. Starch is another carbohydrate, as is also the- 

 woody portioin of plants. The carbohydrates, as we shall soon see, con- 

 stitute a Large portion of all the food consumed by man or animal. In the 

 body the carbohydrates furnish heat and energy. They also serve as the 

 main source for furnishing fat to the tissues. The carbohydrates can 

 not build up the muscles, but the y may nourish them and preveint their 

 waste. The sugars in plants an d fruits, the starch in tubers, roots and 

 stems, and the woody fiber of the leaves, stems, etc., constitute the car- 



