When flour is mixed with water, the proteins in the flour bond together to form a gum-like material called gluten. The gluten is found in the starchy center—the endosperm—of the grain (the only component that remains after the refining process). The bran of the whole wheat flour cuts those gluten strands and creates a denser and heartier bread product.
Gluten gives bread its elasticity and it traps the gas formed by leavening agents, like yeast or baking powder and soda.
Soft wheat flour has less protein, and therefore weaker gluten, which allows baked goods to have a more delicate texture. Soft wheat flours, like all-purpose flour, are usually about 8 to 12 percent protein, while hard wheat flours, like bread flour, contain around 12 to 15 percent protein.
Soft wheat flour
