Author Topic: Lagering on or off yeast?  (Read 644 times)

Offline dak0415

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Lagering on or off yeast?
« on: June 18, 2010, 07:09:36 AM »
Just wondering what the experts have to say.  Rack to secondary for a couple of weeks at 32 deg.  Filter-->keg, carbonate and ignore for 4-8 weeks at 32 deg or leave in secondary for 6-8 weeks.  I'm talking Lite Lager, german pils and Oktoberfest (<1.055 OG), not Dopplebocks.

Dave
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Offline majorvices

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Re: Lagering on or off yeast?
« Reply #1 on: June 18, 2010, 07:11:45 AM »
The real experts say you are better off getting it off the yeast if possible. That said, I often lager on the yeast because I'm lazy. I can't really tell a noticeable difference. Of course, never longer than 2 weeks or so.
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Offline dmtaylor

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Re: Lagering on or off yeast?
« Reply #2 on: June 18, 2010, 07:45:38 AM »
As an experiment, I left my last Vienna lager in primary for over 2 months.  Plastic bucket.  I did the primary and the lagering in the same bucket.  It turned out just fine -- in fact it scored a 2nd place ribbon in competition.  http://buzzbrewclub.org/wp/brew-off/16th-boneyard-brewoff/

No worries.

Of course, maybe I just got really lucky.  But I do think the fears of autolysis and whatnot are FAR overblown.  At least for homebrewers, where we don't have zillion-barrel systems and several FEET thick of yeast settled out on the bottom of the fermenter.
Dave

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Offline redbeerman

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Re: Lagering on or off yeast?
« Reply #3 on: June 18, 2010, 07:57:29 AM »
At normal (for homebrewers) lagering temperatures, the autolysis process will be very slow.  It doesn't surprise me that you had no ill effects on the beer from two months on the yeast.  If temps are in the mid 50's and above, however, I doubt the results would be the same.
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Offline wingnut

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Re: Lagering on or off yeast?
« Reply #4 on: June 18, 2010, 08:02:41 AM »
Dave,

Based on my experience over the past few years with Vienna Lager (9 batches bottled so far, one lagering right now), I have the following thoughts:

If you have a healthy pitch of yeast, you can leave the beer on the yeast once fermentation is done… popular wisdom these days is that you can leave the beer on the yeast for an additional 3 to 5 weeks without any negative effects.  (I once did 7 weeks with the beer constantly below 55F with no noticeable negative effects)  Essentially, if you start with healthy yeast and keep the yeast cool after fermentation, the yeast will last a long time before dying off and passing negative flavor compounds. 

I personally, think my best lagers (and the BJCP judges tend to agree), are the ones that I leave on the yeast for a few extra weeks. 

At the end of fermentation, the yeast tends to re-adsorb many of the flavor active compounds produced while multiplying.  The more contact the yeast have with the beer, the more of these compounds can be adsorbed.  One way to increase beer/yeast contact is what  Budweiser does by tossing in steamed Beechwood chips during the aging process.  This creates a lot of surface area for the yeast/beer contact and this greatly speeds up the “cleaning-up” process.  However, by letting the beer sit in the carboy/bucket for an extra week or two, this accomplishes the same thing. 



As for Filtering… I do not filter, but I would recommend waiting 6 weeks to filter, weather you leave the beer on the yeast or not, since filtering strips out the yeast from the beer, and much of the flavor change in lagers is due to yeast presence.    However, in my opinion, after 6 weeks, the yeast are no longer doing much to help the beer and filtering them out will have no negative effects.

Hope that helps!
-- Wingnut - Cheers!

Offline dak0415

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Re: Lagering on or off yeast?
« Reply #5 on: June 18, 2010, 08:04:27 AM »
You misunderstand.  I don't mean leaving it in primary to lager.  I mean, lager in secondary, or filter and lager in the keg for 6-8 weeks.

Dave Koenig
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Offline richardt

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Re: Lagering on or off yeast?
« Reply #6 on: June 18, 2010, 08:08:59 AM »
dak0415,
If you filter (presumably to remove the yeast and colloid-proteins that may cause haze) and keg, then what is the reason for lagering for 6-8 weeks in the keg?  What is happening then (and how)?

Offline dak0415

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Re: Lagering on or off yeast?
« Reply #7 on: June 18, 2010, 09:09:34 AM »
dak0415,
If you filter (presumably to remove the yeast and colloid-proteins that may cause haze) and keg, then what is the reason for lagering for 6-8 weeks in the keg?  What is happening then (and how)?
I would guess aging out of some sulfur compounds, I don't know, that's why I'm asking you guys!
Dave Koenig
Anything worth doing - is worth overdoing!

Offline pyrite

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Re: Lagering on or off yeast?
« Reply #8 on: June 18, 2010, 09:37:34 AM »
When you lager a lager beer, the yeast is what softens and cleans up the undesirable by-products.  Even if you rack off the yeast cake there are still plenty of yeast cells in-suspension to get the job done (that's why we lager), but if you filter the yeast out then the yeast can't help you out and you will still be left with undesirable components.  If you want to get rid of sulfur, you can just scrub the sulfur out.  To scrub the sulfur out, you can just drop a diffusion stone into the bottom of the vessel and purge through diffusing CO2 into the sulfur containing beer..
« Last Edit: June 18, 2010, 09:39:23 AM by pyrite »
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