Dekoktiomäskäys

Dekoaktiomäskäys, also known as decoction mashing, is a brewing technique used in the production of beer. It involves periodically drawing off a portion of the mash, boiling it, and then returning it to the main mash. This process is believed to aid in the breakdown of starches into fermentable sugars, leading to a more efficient conversion of grain into alcohol.

The decoction process typically involves at least one, but often two or three, decoction steps. In a single decoction mash, a portion of the mash is removed and heated to boiling. This heated portion is then returned to the main mash, raising its temperature and activating different enzymes. Multiple decoction mashes involve repeating this process at different temperature rests, targeting specific enzyme activities.

Historically, decoction mashing was a common method, especially in Central Europe, as it allowed brewers to achieve precise temperature control in mash tuns that lacked modern heating mechanisms. The boiling step serves to gelatinize starches and denature enzymes, allowing for more complete starch conversion and a more robust malt flavor.

Modern brewing often utilizes infusion mashes, where the entire mash is heated gradually to different temperature rests. However, some craft brewers still employ decoction mashing for its perceived benefits in flavor development and to achieve traditional beer styles. The technique requires careful monitoring and execution to ensure optimal results.