Germ particles will be flattened by later passage through the smooth reduction rolls and can be easily separated. The reduction rolls reduce the purified, granular middlings, or farina, to flour. The process is repeated over and over again, sifters to purifiers to reducing rolls, until the maximum amount of flour is separated, consisting of close to 75 percent of the wheat. The various grades of flour produced in the milling process are shown on the chart below. The remaining percentage of the wheat kernel or berry is classified as millfeed - shorts, bran and germ.
Bakers buy a wide variety of flour types, based on the products they produce.
Occasionally short patent flour is available in retail stores. This process produces a higher quality whole wheat flour than is achieved by grinding the whole wheat berry. It has been known for centuries that freshly milled flour makes a lesser quality baked product. In the old days, flour was stored for a few months to mature, or naturally oxidize. This whitened the flour and improved its baking characteristics.