Whole-wheat flour is produced from grinding the full wheat berry (kernel). All parts of the wheat berry are used in the flour including the bran, germ, and the endosperm, which when milled, creates the speckled brown color that is characteristic of the flour. Three granulations (particle size) of whole-wheat are produced: fine, medium, and coarse.
The particle size influences the rate liquid is absorbed into the flour. Finer grained flour absorbs liquid at a faster rate than medium or coarse grains, thus affecting the preparation of the dough.Fine grain whole-wheat flour is used for all types of baked goods, such as breads, rolls, and pastries. Medium grained can be used for the same types of foods, but will provide a coarser crumb. Coarse whole-wheat flour has a much larger bran particle and consequently is most often used to provide breads with natural, nutty flavors and rough textures.