With using an igloo cooler for a mash tun, I have mainly stuck with single infusion mashes for the simplicity. These are easier to maintain, and with today's well-modified malts lessening the need for stepped mashes, a lot of recipes that can be found in various sources today only call for a single infusion mash. However, I recently came across a recipe that called for a stepped mash and I was interested in trying to replicate this recipe as closely as I could so I looked at ways to achieve the steps and decided on using decoction.

The June-July 2020 issue of Craft Beer and Brewing had an article on "Why Decoction Matters" which outlined some of the reasons for still using this method and some different ways of achieving it. It suggests that the traditional styles of Bavaria and Bohemia - pilsner, bock, schwarz-bier, hefeweizen, and others can't truly be replicated without a decoction mash. For lagers, decoction provides two clear differences: taste and mouthfeel with a fuller body and richer flavor, as well as other advantages.

The Craft Beer and Brewing article lists two techniques for decoction mashing schedules.

Hochkurz Decoction Technique

The Hochkurz technique is highly recommended for homebrewers as a standard decoction and works really well for pale lagers and weissbier. This approach skips the protein rest. The steps to perform a Hochkurz include:

• Start with a standard infusion mash starting at 144°F for 30 to 45 minutes.
• To hit the next rest, pull about a third of the mash to a separate pot, boil for 5 minutes, and then return it to the main mash until you bring it up to the target temperature of 160-162°F
• Hold at this temperature for another 30 to 45 minutes.
• Again, pull about a third of the mash to a separate pot, boil for 5 minutes, and then return it to the main mash until you bring it up to the target temperature of 170-172°F to mash out for about 10 minutes.

The first time I attempted this using about a third of the mash to boil resulted in not reaching the target temperature likely due to my lower boiling temperature at altitude so I need to pull more than a third of the mash. Palmer's "How to Brew" has a calculation using the volume and boiling temperature to more accurately achieve the target temperature. I will add this to my calculation page at some point.

Kesselmaische Decoction Technique

The Kesselmaische technique is highly recommended for homebrewers who can directly heat their mash tuns. The steps to perform a Kesselmaische include:

• Start with a standard infusion mash protein rest starting at 122°F for 10 minutes.
• Follow by directly heating the mash up to 142°F
• At this point, the thin, liquid portion of the mash - roughly 20 percent - is pulled out and held at temperature while the thick mash itself is boiled as a decoction for 10 to 30 minutes.
• The thin part of the mash is then added back to the mash tun for a saccharification rest at about 162°F for 30 minutes before continuing to mash out.