Kunze on Maturation

Kunze’s Technology Brewing and Malting covers many approaches to fermentation and maturation. I made notes below on a few that look useful in my brewery.

All these methods are meant for use with a cylindroconical tank, which I don’t have. Temperatures below are converted from the Celsius ones Kunze provides (why I use Fahrenheit for temperature when I use metric for everything else is a different topic) and rounded to the nearest degree. Homebrewers can probably ferment a couple degrees warmer since we don’t have the middle-of-the-tank hotspots big breweries have.

Cold Fermentation—Cold Maturation

1. Pitch at 43-45ºF
2. Let rise to 46-48ºF over two days
3. Maintain for two days
4. Cool to 37-39ºF
5. Transfer
6. Cool slowly to 30ºF
7. Store 1-5 weeks

I’m not a fan of this one because the lack of a diacetyl rest makes me nervous.

Pressureless Warm Fermentation—Cold Maturation

1. Pitch at 46ºF
2. Let rise to 54-57ºF over two days
3. Wait about a week for diacetyl to break down
4. Crash to 30ºF
5. Store 1-5 weeks

Promising. I normally put about 0.5 bar on every fermentation, just to make it easier to take samples and such, but I consider that basically “pressureless.”

Pressure Fermentation

1. Pitch at 50ºF
2. Let rise to 57ºF over two days
3. At 50% attenuation, raise pressure
4. Crash to 30ºF
5. Store 1-5 weeks

Also promising. I would consider 1 bar or more to be a “pressure fermentation.” Some brewers have claimed great success going as high as 3 bar, but I consider that extreme and impractical on my system.

Cold Fermentation—Warm Maturation

1. Pitch at 43-45ºF
2. Let rise to 46-48ºF over two days
3. At 50% attenuation, let rise freely to 54-55ºF
4. Once diacetyl has broken down, transfer & crash to 30ºF

Also promising and similar to what I’ve done in the past.

Again, Kunze covers several other approaches that are worth reading about. I’m just much more likely to use one of the above on my current system.