The yield of flour obtained from wheat in the milling process. A 100% extraction (or straight-run) is wholemeal flour containing all of the grain; lower extraction rates are the whiter flours from which progressively more of the bran and germ (and thus B vitamins and iron) are excluded, down to a figure of 72% extraction, which is normal white flour. Patent flour is of lower extraction rate, 30–50%, and so comprises mostly the endosperm of the grain. See also bread.
Flour. Cross-section of a grain of wheat
Subjects: Medicine and Health.