1. Wheat grains consist of an outer covering, largely silica, removed before milling.

2. Three layers of bran coats, in the forms of cells, containing mineral matter, gluten, oil, etc.

3. A layer of cells, chiefly gluten and other proteid matter.

4. Centre and largest part of the grain made up of cells, of which starch is the chief content.

Starch And Gluten

Mix wheat flour and water to form a dough. Let stand a short time, then wash it on a sieve over a pan of water. Let the water settle; and, when it is poured off, a white mass, which, when dried, is fine as dust, is found in the pan. This is starch. And the doughy, gray, elastic mass left on the sieve, which may be taken up in the hands and pulled like candy, is gluten. These are the chief constituents of flour, and the relative proportion of these two substances determines the character of the flour. Gluten gives a strong, gray flour of slightly bitter taste, which will take up a large quantity of water. Such flour "spends well." Starch gives a more delicate flour of sweet taste, which takes up, relatively, a small quantity of water. The tenacious, elastic gluten is needed in yeast mixtures, to hold the carbon dioxide that lifts up the dough and makes it light. But it is not as desirable in cake and pastry, where tenderness and delicacy are sought for. The relative proportion of starch and gluten in grains depends largely upon the soil and the climate in which the grain is grown. Hard spring wheat, planted in the spring and harvested in August or early September in Minnesota and in North and South Dakota, is particularly strong in gluten, and contains a minimum quantity of starch. Flour made from such wheat is designated as bread flour. Winter wheat is a softer variety raised in the Middle and Southern States. It is planted in the fall, and harvested in the following June or July. Flour made from this wheat is designated as pastry flour, as it is well adapted to the purpose indicated by the name.