REPORT OF THE CHEMIST. 



The wheat as it enters the mill is subjected to a series of operations 

 which removes dirt, foreign seed, the fuzz at the end of the berry, and 

 a certain portion of the outer coats, through the agency of a run of 

 stones and brushes. The result of this operation is to lower the amount 

 of inorganic matter or ash, and to increase or decrease the other con- 

 stituents but slightly, the albuminoids being a few tenths of a per cent, 

 greater in amount. The point from which a convenient start may be 

 made is at the first break. 



The chop from the first rolls is very marked in its difference in com- 

 position from the original wheat. It of course has less fiber, and also, 

 it is seen, less ash, oil, and albuminoids j in fact, it is fttarchy. It con- 

 tains more water, owing to the fact that its comminution has allowed 

 it to absorb the moisture from the air, and in general it will be observed 

 that the coarser or more fibrous a specimen is the less water it contains, 

 while the finer material holds more. For example, the percentage of 

 water in several portions of the grain is as follows : 



Per cent 



OrigiDal grain 9. 66 



Ready for the break 8. 23 



Chop^from first break 12. 52 



Fifth break 7. 62 



Bran 10.91 



The heat caused by the friction of the process, of course, is an active 

 agent, as may be seen on comparing the original grain and that ready 

 for the break. The question of the relation of the various products to 

 humidity is, however, considered in greater detail in another portion of 

 this bulletin. 



The starchy chop from the first break is carried off to the various 

 purifying and grading machines, but for the present it will be left, as 

 it is desirable to follow the breaks to the end. 



The tailings from the first scalper, consisting of the wheat-grain split 

 open along the crease, which serve to feed the second break after the 

 cleaning which they undergo, vary but little from the wheat which goes 

 to the first break. There are slight differences which must be attrib- 

 uted to the difficulty of selecting and preparing for analyses samples of 

 the product of the different breaks, the finer chop having a tendency to 

 sift out from the lighter bran, but they are not great enough to vitiate 

 the conclusions. In the first break so little is done, except to crack 

 open the wheat and clean it for the following rolls, that only a small 

 change should be expected. 



The chop from the second break is more from the center of the wheat- 

 grain. It contains less ash, fat, and albuminoids than any of the break 

 products, and includes, as was shown by^our preliminary investigation, 

 the greater portion of the endosperm. 



The tailings supplying the third break already show, owing to the 

 greater amount of chop produced on the second break, a marked in- 

 crease in those constituents which are peculiar to the outer portions of 

 the grain ; that is to say, there has been a marked increase in ash, fiber, 

 and albuminoids. This increase becomes still more apparent from break 

 to break until the bran alone is left, which contains more ash and fiber 

 than any other product of the wheat. The several chops increase in a 

 like manner, the last or sixth break chop holding more albuminoids 

 than the bran, and even any other of the resulting material. This is 

 probably due to the comminution of the bran in the last break, and 

 consequently, as will be seen, the middlings from this chop are richer 



' 7 A — '84 



