Decoction mashing

Decoction mashing

Decoction mashing involves boiling a portion of the grains and then returning them to the mash, raising the temperature. The boiling extracts more starches from the grains by breaking down the cell walls. It can be classified into one-, two-, and three-step decoctions, depending on how many times part of the mash is drawn off to be boiled. Decoction is a traditional method and is common in German and Central European breweries. It was used out of necessity before the invention of thermometers allowed for simpler step mashing, but the practice is still in use for many traditional beers because of the unique malty flavor it lends to the end product. Boiling part of the grain results in Maillard reactions, which create melanoidins that create rich, malty flavors.