A Craft Beer & Brewing Magazine reader recently asked us the following question:
What is a triple-decoction mash, and why would I need to do one?
Triple-decoction mashing is a traditional brewing technique used extensively in Europe for brewing beer. A decoction mash includes at least one step where a portion of the mash, including the grains, is removed and heated in a separate vessel to boiling temperature and then mixed back in with the main mash to raise the temperature of the mash. By “decocting” a portion of the mash and heating it to a boil, you can raise the temperature of the mash for each step, much as you would when adding water for a traditional infusion mash.
As with other mash techniques, the mash may be completed in one or more stages or steps where the grain is rested at different temperatures. Decoction mashing was developed in the period before thermometers were in wide use. Drawing the correct percentage of the mash and bringing it to a boil at each step produced a consistent temperature for each step.