Burr mill

Burr mills do not heat the ground product by friction as much as blade grinders ("choppers"), and produce particles of a uniform size determined by the separation between the grinding surfaces.

[1] Food burr mills are usually manufactured for a single purpose: coffee beans, dried peppercorns, coarse salt, spices, or poppy seeds, for example.

Domestic pepper, salt, and spice mills, used to sprinkle a little seasoning on food, are usually operated manually, sometimes by a battery-powered motor.

The size of the grind is determined by the width between the two burrs, into which the coffee beans fall and are ground a few at a time.

[5] A finer grind allows a larger surface area to come into contact with the water, which yields a more complete extraction of caffeine and flavor.

Lower-cost models generally use a small electric motor to drive a series of reduction gears, while better constructed and more costly examples use a larger commercial motor and a belt, with no gear reduction to spin the burrs.

Doserless versions remove the bin and dosing function, and the grinder outputs the ground coffee directly into an espresso machine portafilter or into another container.

Many hard spices are available in containers incorporating a simple cone burr grinder, intended to be discarded when empty.

Laura Ingalls Wilder's novel The Long Winter describes a family grinding wheat in a coffee mill to make flour during months of hardship.

The grooves on the Peugeot mechanism were individually cut into the metal and then case-hardened, making them very durable.

Stainless steel: One of the most suitable and durable materials for grinding peppercorns and coffee beans.