Flour production

Milling of flour is accomplished by grinding grain between stones or steel wheels. Today, "stone-ground" usually means that the grain has been ground in a mill in which a revolving stone wheel turns over a stationary stone wheel, vertically or horizontially with the grain in between. Many small appliance mills are available, both hand-cranked and electric.

Flour dust suspended in air is explosive, as is any mixture of a finely powdered flammable substance with air,[1] see Lycopodium. Some devastating and fatal explosions have occurred at flour mills, including an explosion in 1878 at the Washburn "A" Mill in Minneapolis, the largest flour mill in the United States at the time.[2]