This section is from the book "Elements Of The Theory And Practice Of Cookery", by Mary E. Williams. Also available from Amazon: Elements Of The Theory And Practice Of Cookery; A Textbook Of Domestic Science For Use In Schools.
Having explained the milling process, the miller may show you a quantity of yellow disks the size of a pinhead. These are germs flattened out by the smooth rollers, and sifted out. If this were not done, the diastase in them (p. 81), which prepares the starch for digestion by the seedling, would spoil the flour by working in it the same change that it does in the seed.
Lastly, you may see the finished flour packed by machinery into barrels and sacks to be sold, some of it, perhaps, to the farmers who raised the wheat it is made of, some to city people who never saw a wheat field.
Flour made by the process described above contains as much of the foodstuffs of the wheat as can be retained while excluding the germ and the bran. Most mills make several grades of such flour. The best quality, known as "high-grade patent," is made from middlings, as described above. Lower grades are sifted out after each break.
True graham flour is unbolted meal made from whole wheat including the bran. Imitations sold as graham flour are mixtures of low-grade flour, bran, and other by-products of milling. So-called "entire wheat" or "whole wheat" flour has not always been what its name indicated. It contained the aleurone but lacked part of the bran and much valuable mineral matter. It has been proposed to call such flour bolted wheat meal, and graham flour whole or unbolted wheat meal, so that the housewife may know what she is getting.
Hard spring wheat, being rich in gluten, yields such flour.
You may know it (l) by its creamy white color, (2) by its gritty feeling, (3) by its caking but slightly when squeezed in the hand, and (4) by its capacity for absorbing water.
One quart of good flour will take up nearly one and one-half cupfuls of water in making dough stiff enough for yeast bread.
For further development of topics treated in this section see: -
Edgar : Story of a grain of wheat.
Grant : Chemistry of breadmaking. Ch. VIII, Milling.
Sherman: Food products. Pp. 268-279.
Doolittle : Why bleached flour should not be used. (In Housewives'
League Magazine, June, 1914.) Snyder : Human foods. Ch. 10. U. S. Dept. of Agriculture : Bureau of Chemistry Bulletin.
164. Graham flour. Bureau of Plant Industry. Bulletin 20.
Manufacture of Semolina and Macaroni.