Probably the most striking difference in the average mineral
composition of the grain of wheat is the very much lower proportion of
phosphoric acid, and of magnesia also, in the dry substance of the
best matured grain; and it is now known that these characteristics
point to a less proportion of bran to flour, or, in other words, of a
greater accumulation of starch in the process of ripening, and
consequently of a whiter and better quality of bakers' flour. The
study of the chemical composition of wheat and its products in the
mill, therefore, and of the amount of fertilizing matters (nitrogen,
phosphoric acid and potash) removed from the soil by the crop, becomes
of direct interest not only to the producer from whose soil these
ingredients are removed, but to the consumer of the byproducts as
well, who desires to know what proportion of these elements of
fertility he is returning to his own soil in the different products he
may use as animal food. It is desirable also to determine what is the
average composition of wheats and the flour made from them, in order
to see in what direction efforts should be turned, by the selection of
seed wheats, to improve the present varieties for the production of
the best quality of flour. This can only be done after we determine
what variation there is for different years due to climatic influences
and variations of soil, for it has been shown in our former papers
that environment very largely influences the quality of wheat grain,
and also of the flour. When these have been determined, than we may
hope to be able to determine which factors under our control enter in
to permanently improve the better flour-producing quality of wheats.
A mixture, in equal proportions, was made of Clawson, Mediterranean,
and early amber wheats, and submitted to the mill, using the Hungarian
roller process. From this mixture for each one bushel of the grain of
60 lb. weight was furnished the following proportion of products:
Lb. per
Bushel. Per cent.
Flour. 44 73.3
Middlings. 4 6.7
Shipstuff. 2 3.3
Bran. 10 16.7
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Total. 60 100.0
These data furnish us a means of estimating the amount of the
different ingredients removed in the various products in one bushel of
wheat with the foregoing component parts.