First Lager: Questions...

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Evan!

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Last Friday, I brewed my first Lager (and second AG brew), a Pilsner. OG was 1.055, about 73% efficiency. Good so far. I pitched a large (1000mL) starter of Wyeast Bohemian Lager yeast and aerated fully. Here's where my inexperience with lagers comes in...

From all I've read and heard, lagers take like 4 weeks to finish fermenting. And about the time it's done, you raise the temp up for a diacetyl rest. Okay. So here's what I did: I pitched the starter, aerated, and waited at 60f for signs of visible fermentation. As soon as I saw airlock bubbles and krausen, I moved the carboy to the lagerator and dropped the temps to the low 50's. Fermentation was pretty steady for a few days.

Here we are at day 5. I figured this would be a long slow process, but it looks like it's done. The krausen has fallen and airlock activity has slowed considerably...maybe a bubble every 15-20 secs.

So, what's the deal? First off, if lagers are bottom-fermenting, why was there a krausen? I didn't expect that. Second, why did it ferment so quickly? Or is it probably not done? Is there some kind of "initial fermentation phase" where it's quick, and then 3 weeks of very slow fermentation? When should I do the diacetyl rest? Also, since the top stays closed (obviously) on my lagerator (chest freezer), when I open it up, the blast of CO2 hits me in the face and knocks me back a few feet. Strong shyte. Is all this cooped-up CO2 a problem for the beer?

Of course, the only way to know whet the deal is, is to take a hydro reading, but I wanted to get your thoughts on it before I bothered popping the stopper out. Thanks in advance. :mug:
 

david_42

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Generally, I've seen 65-70% attenuation in the first week and then very slow fermentation down to 80% or so. 1-2 bpm. My Schwarzbier took three weeks for the last 5 points and finished 3 points lower than the London ale yeast I used on the other half of the batch.
 

sonvolt

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Primary fermentation times can be short. It secondary fermentation/lagering that you should do for 4 weeks. I have had lagers ferment out completely in as little as 10 days. After that, you should slowly lower temperatures to near freezing and then lager for 4 weeks.

Krausen is normal in lagers.

Do a hydrometer reading to see where the beer is at in terms of gravity.
 

boo boo

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It started fast because you made a nice starter, areated well and pitched into relatively warm wort (60f). I pitch the same into wort that is at 50f and get fermentation times of 2 weeks to 3 weeks including a few days for a rest.
BTW, my starter is at 45f when I pitch.
 
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Evan!

Evan!

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How about the diacetyl rest? I've heard that I should bring it up to room temp, while Wyeast's product description for the Bohemian says the rest should be @ 58f. So, when do I do the rest, and for how long, and at what temp?

Sorry, I don't mean to bombard you guys with q's, but there's so much conflicting information out there, I just need some firsthand experience.

EDIT: I consulted Palmer's How To Brew. He said I should have pitched it into cooled wort...but that my method will work, just that there's a chance of more diacetyl. So he says to rest it at 55-60f for 24-48 hours, then slowly drop it to near-freezing temps.

A couple other points he mentions:

-The temperature difference between the primary phase and the lager phase should be roughly 10°F.
-Nominal lagering times are 3 - 4 weeks at 45°F, 5 - 6 weeks at 40°F, or 7 - 8 weeks at 35°F.

So, since my primary has been around 52f, I should lager at about 42f for 4-5 weeks. He also said that darker, stronger beers require more lagering...but since this is a pilsner, I shouldn't need more than this, I suppose.
 

boo boo

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when you lager is estimated to be 2/3 done then raise the temp to around 60ish until finished. Rack and lager at 34f for a few months. Temperture and time are important to lagering.
 
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Evan!

Evan!

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okay, so, if my OG was 1.054, and I'm expecting 69-73% attenuation with this strain (probably on the higher end because my mash temps were on the lower range, and I made a huge starter and aerated fully), my FG should end up being about 1.014 or 1.015. so, 2/3s of the way there would put me at 1.027, roughly. So at 1.027, bring 'er up to 58f for 2 days, then rack to secondary and slowly drop temps to about 40f, where it sits for 4-5 weeks.

Right?
 

boo boo

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That should get you there. If you lager at a higher temp (40f) then your lagering time decreases but the lower temp/longer time frame makes for a smoother lager.
 

Mikey

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Evan! said:
A couple other points he mentions:

-The temperature difference between the primary phase and the lager phase should be roughly 10°F.
-Nominal lagering times are 3 - 4 weeks at 45°F, 5 - 6 weeks at 40°F, or 7 - 8 weeks at 35°F.

So, since my primary has been around 52f, I should lager at about 42f for 4-5 weeks. He also said that darker, stronger beers require more lagering...but since this is a pilsner, I shouldn't need more than this, I suppose.
He might be on to something, but this flies in the face of German and Czech brewing traditions.

His is just one guy's opinion.
 

dantodd

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boo boo said:
when you lager is estimated to be 2/3 done then raise the temp to around 60ish until finished. Rack and lager at 34f for a few months. Temperture and time are important to lagering.
Just to clarify, boo boo meant fermentation is 2/3 done not lager.

Most folks recommend lagering as close to freezing as you can.
 
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