(2) Whole wheat flour—the first outer coat of cellulose with its valuable mineral contents is removed before the seed is ground.
(3) White flour—only the central white part of the seed is ground.
Note.—The pupils should be given specimens of fall wheat to examine, so as to compare the outer coat of cellulose with the central white part of the grain.
3. Composition of white flour:
(1) Starch—a fine, granular, white substance
(2) Gluten—a sticky, yellowish, elastic substance (a protein food).
To find the substances in white flour, each pupil should mix half a cup of bread flour with enough cold water to make a dough. She must then be taught to knead it. This knowledge will be of use later in the bread lessons. After it is thoroughly kneaded until it is smooth and well blended, the dough should be washed in several waters. The first washing water should be poured into a glass and allowed to settle, to show the starch. After all the starch is washed away, the gluten will remain.
The gluten may then be put into a greased pan and baked, to demonstrate that it admits of distention, and also to show that it may be stiffened permanently by heat into any distended shape. The baked gluten should be reserved to be used as a specimen in succeeding lessons.
4. Kinds of wheat flour:
(1) Bread flour—contains much gluten.