THE MILLING OF WHEAT 273 



early nineties. The mixing is done by means of the elevator 

 machinery. Each mill generally has its own elevators for stor- 

 ing the grain. Different bins receive the different grades of 

 wheat from the cars. The mixing and other manipulation of 

 grain may take place in the elevators, or by a separate system 

 of machinery in the mill proper. The quality of wheat varies 

 so much with climate and season that it is practically impos- 

 sible to prevent corresponding variations in flour without mix- 

 ing. In our country much winter wheat is grown, and the best 

 grade of flour can be made from it only by mixing it with the 

 hard spring wheat. The spring wheats bear a higher and more 

 uniform percentage of gluten, and herein lies their great value 

 for mixing purposes. It is also claimed that spring wheat flour 

 is more regular in the time required to mature in the bread 

 dough. These are the reasons why spring wheat brings a 

 higher price in the markets. 



Three Fundamental Processes are passed through by the grain 

 in the milling: (1) Cleaning; (2) tempering; and (3) grinding 

 or milling proper. 



CLEANING. In this three objects are held in view: The re- 

 moval of foreign seeds from the grain; the securing of clean 

 wheat berries that are free from dust and other adherent for- 

 eign matter; and the removal of small particles of bran which 

 would drop off afterwards and find their way into the flour. A 

 special machine has been designed for the removal of each kind 

 of foreign seed, such as that of other grain and of weeds. In 

 the main, two different methods are used in the removing from 

 the wheat berry all undesirable matter adhering or attached to 

 it. In each method, machines adapted to the purpose are 

 utilized. One method is known as dry cleaning, in which the 

 wheat is passed through scourers. In the other method, the 

 wheat is washed with water and subsequently dried. Each 

 method has its advantages for different conditions of the grain, 

 but some millers wash all wheat. 



TEMPERING consists of putting wheat in the best of condition 

 for milling. The coats of the berry must be so tough that the 

 bran flakes out in one large piece in the grinding, and the in- 

 terior of the grain must be in such condition as to give the 

 largest yield of flour. There are nearly as many methods of 

 tempering as there are mills, for each miller uses a process that 



