Milling
Milling is the mechanical processing of grain to separate or reduce it into flour, meal, bran, and other fractions.
Roller mill: A machine that uses pairs of rotating rollers to crush or shear grain into progressively finer particles. Its staged, adjustable rolls are the basis of modern flour milling.
Wheat: A cereal grass cultivated for grain, widely milled into flour for food. Its kernel structure and protein composition make it the principal grain for bread flour.
Flour: A finely ground powder made from cereal grains or other starchy plant foods. Flour is the principal product of grain milling and varies with extraction and grain type.
Quern-stone: A hand-operated stone tool for grinding grain into meal or flour. Querns represent an early direct method of mechanically reducing grain.
Stone grinding: A grinding method that reduces grain between opposing stones. Stone grinding contrasts with roller milling in its surfaces, action, and typical product.
Milling fractionation: The separation of grain into distinct products such as flour, bran, and germ during processing. Separating these fractions lets millers control flour composition and yield.
Cereal grain: The edible seed of a grass crop, including wheat, rice, maize, and barley. Milling methods begin with the structure and composition shared by cereal kernels.
Whole-wheat flour: Flour containing the bran, germ, and endosperm of the wheat kernel in their original proportions. It retains fractions that conventional white-flour milling separates out.
Saddle quern: A stationary concave stone on which grain is ground with a handheld rubbing stone. Its back-and-forth motion shows how early milling relied on human power.
Hammer mill: A mill that reduces material by repeated impacts from rapidly rotating hammers. Impact milling offers a different particle-reduction mechanism from roller systems.