Author Topic: Lager Fermentation - Stuck??  (Read 1075 times)

Offline cmooreseymour

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Lager Fermentation - Stuck??
« on: January 09, 2015, 12:38:31 PM »
My first attempt at using lager yeast has hit a wall.  I used Zainasheff's dopplebock recipe and two vials of WLP 820 yeast for a huge starter.  Fermenting at 50 degrees (with a diacetyl rest at 58 degrees from day 14 to day 18), here is my gravity schedule:

OG = 1.086, Day 16 = 1.052, Day 24 = 1.038, Day 31 = 1.032, Day 38 = 1.028. Transferred off yeast cake, set up fermentation/blow-off in keg. Day 59 = 1.028. My FG goal is 1.020, but I'm afraid I'm stuck.

Any suggestions on how to reach my FG??  Thanks in advance for the help.

Offline HoosierBrew

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Re: Lager Fermentation - Stuck??
« Reply #1 on: January 09, 2015, 12:45:40 PM »
I would move the beer to a room that's 70F or over and gently rouse the yeast. These two things might spur the yeast into action and (hopefully) eat a few points.  Let it sit there a week and check gravity. Hopefully it'll move a little. If it does, obviously leave it there until you reach a steady reading. Good luck.
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Offline duboman

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Re: Lager Fermentation - Stuck??
« Reply #2 on: January 09, 2015, 01:05:49 PM »
While the fg may be off I have two questions:

Is this with a hydrometer or refractometer?

Have you properly calibrated either device?

If using a refractometer did you convert to account for the presence of alcohol? Either way I would verify with a properly calibrated hydrometer. It should read 1.000 in distilled water at its calibration temp which is usually 68oF. The paper slip will tell you.
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Offline brewinhard

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Re: Lager Fermentation - Stuck??
« Reply #3 on: January 09, 2015, 01:50:00 PM »
When you say a "huge" starter with two vials, what size starter was it?  Stirplate?  How fresh were the vials?  For a lager that big, you would probably need to do at least a gallon starter with the 2 vials on a stir plate to get close. 

My other thought immediately goes to proper aeration and recipe formulation along with what the above poster stated involving your hydrometer readings. 

Big lagers are a tough nut to crack...Be patient, warm it up to 70's and let it sit.  If you are overly concerned with that high of a FG you could always try pitching an active starter of an attenuative neutral ale strain (think 1056/001) to try and get a few more points shaved off.

Offline cmooreseymour

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Re: Lager Fermentation - Stuck??
« Reply #4 on: January 09, 2015, 02:13:07 PM »
Great ideas so far!!

My hydrometer is brand new and I calibrated it in distilled water at 68 degrees at 1.000. 
I can taste the residual sugar in this beer right now. 
My starter was one gallon, but don't have a stir plate.
I aerated the wort as much as humanly possible before pitching the starter.

My plan is to move from my temp controlled freezer to a closet to increase the temperature.
My temp controlled freezer is in the garage and have tried heating it to 60+ in the winter with no luck.

Keep the suggestions coming.  I greatly appreciate the speedy feedback!

Offline brewinhard

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Re: Lager Fermentation - Stuck??
« Reply #5 on: January 09, 2015, 02:15:34 PM »
Is your hydrometer calibrated for 68F then?  I only ask b/c some are 68 and some are 60.  That would not make an 8 point difference though.  It sounds like you might have under pitched a bit and probably did not get as much O2 into the wort as was required for such a cold lager. 

Offline Wort-H.O.G.

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Re: Lager Fermentation - Stuck??
« Reply #6 on: January 09, 2015, 03:33:24 PM »
Great ideas so far!!

My hydrometer is brand new and I calibrated it in distilled water at 68 degrees at 1.000. 
I can taste the residual sugar in this beer right now. 
My starter was one gallon, but don't have a stir plate.
I aerated the wort as much as humanly possible before pitching the starter.

My plan is to move from my temp controlled freezer to a closet to increase the temperature.
My temp controlled freezer is in the garage and have tried heating it to 60+ in the winter with no luck.

Keep the suggestions coming.  I greatly appreciate the speedy feedback!



1gal no stir plate starter may have been under pitched for beer this big. not knowing everything, you would have wanted about 700B cells to pitch, and with 2 vials and say 1.035OG starter just swirling occasionally, you'd be under pitched by as much as 300B cells. might be some of the issue- just something to consider next time.
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Offline cmooreseymour

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Re: Lager Fermentation - Stuck??
« Reply #7 on: January 14, 2015, 04:40:06 PM »
I repitched a 1500 mL starter with WLP 001 yeast at 68 degrees to attempt to save this beer that is stuck at 1.028.  Most likely won't be the best beer I've ever made, but I figured it was that or pour it down the drain.

I've taken OGs of 1.080+ to my goal FG with 2 vial/1 gallon starters before, but not with lager yeast and reduced temperatures.  Next time, I'll have to consider 1.5 gallon and a stir plate.

Any idea if repitching will lead to a drinkable beer?