#25P Decoction Wheat

Eureka, yet another post about a recipe from the old days. April 2011 in this case. This time about my first decoction batch I conducted. Decoction is basically a technique where one heats up only a small part of the mash in a separate kettle and pours it back to the main mash to raise the temperature. Therefore a different technique to raise the temperature of your mash instead of direct heat. Decoction mashes are very common in wheat breweries and some say that it has a major impact on the flavor of a beer.

I did a decoction mash on a small-scale to test how it works. The recipe is straight forward with some acidified malt to adjust the mash pH at the beginning.

Recipe: Decoction Wheat
Numbers: Volume [L] 5 (1.3 gal)
Original gravity 13.5°P (1.054)
Terminal gravity 5°P (1.020)
Color Around 4 EBC
ABV 4.7% (v/v)
Grains: Pilsner malt (4 EBC) 0.52 kg
Wheat malt (4 EBC) 0.65 kg
Acidified malt (9 EBC) 0.025 kg
Hops: Hallertauer (8% AA) 3.3 g and boil for 90 min
Yeast: Wyeast’s #3068 Weihenstephan
Water: Burgdorf Mash: 4 L (1.1 gal), sparge: 5 L (1.3 gal) @78°C (172°F)
Rest: Mash in @40°C (104°F),
25 min @50°C (122°F),
20 min @64°C (147°F),
60 min @71°C (160°F),
10 min @ 78°C (172°F)
Boil: Total 90 min
Fermentation: Primary 14 days @18°C (64°F) in plastic fermenter
Secondary N/A
Maturation: Carbonation (CO2 vol) 3.5 with sugar addition
Maturation time > 3 weeks

04/16/2011: Another pilot batch brew day. Crushed all the grains and mashed in at 40°C (104°F) and then let the temperature rise to 50°C (122°F) by directly heating the mash. After the 25 min rest, I removed 50% of the mash and heated this share up to 71°C (160°F), then let this share rest for 15 min and heated up to a boil and boiled for 20 min. Afterwards, the boiled share was poured back to the main mash to increase the mash temperature from 50°C to 64°C (147°F). After a 20 min rest I increased the temperature again by direct heat up to 71°C (160°F), rested for 60 min and then prepared for the mash out at 78°C (172°F). Sparged with 5 L of 78°C (172°F) water and collected the runnings. Then boiled the wort with the small Hallertauer hops addition for 90 min, cooled the wort down to 20°C (68°F) and added freshly propagated #3068 Weihenstephan yeast.

05/01/2011: Bottled the beer after a primary fermentation step of roughly 14 days and added enough sugar to get a carbon dioxide level of 3.5 vol. Then stored the bottles at room temperature for another seven days and then stored the bottles in my refrigerator.


Aroma: Slight banana aroma, grainy and a bit of sulphur detectable.

Appearance: Yellow-gold, white creamy head, nice carbonation level. Poured the yeast sediment into the glass as well.

Flavor: Rather subtle banana character, hint of grains…

Mouthfeel: Light to medium body, lively carbonation level, short light grainy aftertaste. Easy to drink.

Overall Impression: This is a wheat beer but without any special character I expected from the decoction mashing like some caramel or even some burnt character. In my opinion, the decoction mash did not contribute to additional flavors or aroma I could taste. Either the technique was not right or I simply can’t taste the differences.

I haven’t done any decoction mash since simply because I do not brew any wheat beers anymore (brewed enough of it). However, all future batches of Lambics will be brewed using the traditional turbid mash technique which is kind of a decoction mash technique as well. In this case, my Lambics improved a lot since I switched from traditional infusion mashes to the turbid mash. And I can clearly taste the difference there. Cheers!