12 



THE WHEAT INDUSTRY 



Aleurone 

 Layer 



Seed Coats 



Pericarp 



quality and use of the grain. What we have 

 studied about the physiology of foods may help 

 us to understand the meaning of such terms as 

 cellulose, starch, sugar, fats and oils, and ash. 



All of these mate- 

 rials are in thewheat 

 grain. 



The kernel has 

 several layers in its 



outer portion. The 

 outer ones are com- 

 posed principally of 

 cellulose. They produce the bran in flour mak- 

 ing. One of these layers contains considerable 

 coloring matter. The bran layers make up about 

 five per cent of the weight of the entire kernel. 



Starch Cells ^^^je^> Germ 



FIG. 7. Diagram showing structure of wheat 



Pericarp or Outer Seed Coat 



--Inner Seed Coats 

 "Aleurone Layer 



-Starch Cells 



FIG. 8. Highly magnified section of a portion of wheat grain. 



Just inside the bran, between it and the endo- 

 sperm, is the cereal or aleurone layer of large 

 gluten cells. This division makes three to four 

 per cent of the weight of the grain. 



