Conical Fermenters How Do I Use Them?

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Conical Fermenters How Do I Use Them?

Post by steve_flack » Sun Jan 13, 2008 9:40 am

I have the luxury of a temperature controlled conical which the normal MoreBeer/eBay/Blichmann conicals aren't as standard, but here's what I do.

1. Rack beer to conical (I aerate inline but you could do it after).
2. Chill to pitching temp (18C for most Ales 8C for lager).
3. Pull any trub - especially for lagers.
4. Pitch yeast
5. Allow to warm to 20C for most ales (10C lager) under own steam
6. Allow beer to ferment as normal at appropriate temp.
7. Lagers only: When at 50% apparent attenuation raise temp to 15C.
8. Allow fermentation to finish.
9. Hold at final fermentation temp for 2 days.
10. Crash cool to 5C (or as low as will go).
11. Pull yeast off every day (some yeasts set hard if you let them)
12. Rack after a week to keg.

Ales you can generally rack earlier but I'm pretty methodical about getting most of the yeast to drop with lagers before racking. If using auxilliary finings they are added after the beer has been cooled to 5C for a couple of days. I don't routinely use them however.

The low pitching temp for lagers and the rise to 15C towards the end of fermentation are to reduce diacetyl in the finished beer. Most of the precursor to diacetyl is produced early in the fermentation so by keeping the fermentation cool at that stage you reduce diacetyl. The temp rise at the end just helps the lager yeast clean up after itself and attenuate properly. The downside of a low pitching temperature is that you need more yeast.