Stuck Lager. Repitch?

Brewed a Mai bock 3 weeks ago and over shot my gravity significantly. target 1.070 ended up with 1.090. I said what the heck and went with it hoping for the best. I realize at that gravity I was under pitching with my 2L starter but the fermentation got off to a great start so I thought i was ok.

the gravity has been stuck at 1.040 for the past week. I raised the temperature from 45 to 60 slowly and didnt notice any additional fermentation and now the krausen has dropped completely.

I’m considering throwing in another package of lager yeast and possibly aerating, but not seeing much support for this in the forums.

Any recommendations at this point?

More yeast will probably not help. Aeration is a bad idea. A couple things: Swirl the yeast to get them back into suspension, and add some yeast energizer – this is available at any homebrew shop. Sometimes yeast energizer plus temperature increase is the only thing that will get the fermentation going again. And sometimes, there is just nothing you can do.

I hope you did not rack the beer. Also… is this an extract beer? That might explain the problem if you used an extract with a lot of unfermentable sugars. Extracts differ from brand to brand. If this was an all-grain batch, what was the mash temperature and time? Perhaps you mashed too hot. Or your thermometer is not properly calibrated.

Not too many things you can really do – hopefully the yeast energizer will help. But lots of things to think about as to the possible causes, if you wish to learn from the experience.

its still in primary and this was an all grain batch. I used the Mai bock recipe from jamil’s BCS and mashed at 156 for an hour. I did calibrate my thermometer recently and it was only off by 2 oF, but I’ll check it again.

thanks for the tips. I’ll try the energizer. I was thinking of just bring it all the way up to rmtemp, 68oF. I’ll probably sacrifice some lager character.

Personally I would never mash above 154 F, no matter what “the pope” or anyone else says. I always shoot for 150 F, always mashing 148-152 F, so then it is very rare to have these kinds of problems.

Fermentation is getting close to completion, if it isn’t complete already. As such, it won’t hurt a flea if you warm this up to room temperature. They say you perform a diacetyl rest after 2/3 of fermentation is complete. For a 1.090, with an expected final gravity around 1.023, 2/3 of fermentation happens at roughly 1.045. So you are already past that point and can safely warm up even to 68 F as you have suggested, and it won’t hurt anything, and might help.

I wish you the best.

Are you using refractometer for your readings?

FWIW, Dave, I just mashed a dopplebock at 158, despite fears like yours. I figured, what the hell, it’s just a batch of beer, let’s see what happens. Good news…it worked great and I got exactly the FG I wanted. Although I won’t use higher mash temps all the time, I won’t be afraid to use a higher temp if it’s warranted.

To the OP: if the beer is truly stuck, not finished, you need to pitch a LOT of yeast to get it restarted. Like a qt. of slurry from a brewery or brewpub.

I just knew some crazy hippie like Denny would come on here and prove me wrong… :lol:

Still doesn’t change my mind about 148-152 F for every beer though. 8)

[quote=“dmtaylo2”]I just knew some crazy hippie like Denny would come on here and prove me wrong… :lol:

Still doesn’t change my mind about 148-152 F for every beer though. 8) [/quote]

In general, I almost always keep mash temps in the range you do. But based on my recent experience, I think you owe it to yourself to rethink that for certain styles.

[quote=“Denny”][quote=“dmtaylo2”]I just knew some crazy hippie like Denny would come on here and prove me wrong… :lol:

Still doesn’t change my mind about 148-152 F for every beer though. 8) [/quote]

In general, I almost always keep mash temps in the range you do. But based on my recent experience, I think you owe it to yourself to rethink that for certain styles.[/quote]

What styles have you found a higher temp beneficial?

Nope, I used a hydrometer for gravity readings.

I fermented 3 or 4 lagers in the past at 156 with no problem getting to FG. I was attempting a different lagering schedule that avoids the diacetyl rest by starting fermentation a little below the target temp. this way the fermentation is cleaner off the bat.

for future reference If I did want to repitch but didn’t have another lager cake to pitch onto, at this point in the fermentation would pitching on an ale cake change the beer’s character significantly? say if I kept it in the low 60s?

[quote=“mrv”][quote=“Denny”][quote=“dmtaylo2”]I just knew some crazy hippie like Denny would come on here and prove me wrong… :lol:

Still doesn’t change my mind about 148-152 F for every beer though. 8) [/quote]

In general, I almost always keep mash temps in the range you do. But based on my recent experience, I think you owe it to yourself to rethink that for certain styles.[/quote]

What styles have you found a higher temp beneficial?[/quote]

Specifically, the doppelbock I mentioned. Or pretty much any bock or maibock, too.

[quote=“alechemist”]Nope, I used a hydrometer for gravity readings.

I fermented 3 or 4 lagers in the past at 156 with no problem getting to FG. I was attempting a different lagering schedule that avoids the diacetyl rest by starting fermentation a little below the target temp. this way the fermentation is cleaner off the bat.

for future reference If I did want to repitch but didn’t have another lager cake to pitch onto, at this point in the fermentation would pitching on an ale cake change the beer’s character significantly? say if I kept it in the low 60s?[/quote]

I think if you used a clean ale yeast (something like WY1007) and kept it in the low 60s, it would be OK.

…since my first batch in 1993, we have only experienced a “stuck” fermentation once; the Oregon Common pale ale batch we’re fermenting now with Fermentis Safale K-97. What to do when it’s stuck? The best and only thing I will do is like what Charlie P. says, “Relax, have a homebrew.”

It is Spring in Portland, Oregon; therefore, weather, temperature, our brewhaus conditions, fermentation process: high pitching temperature and it had to be transferred from primary to secondary a week late, etc., all have an impact on yeast behavior. These conditions mean that the yeast we’re using requires patience and time to complete its task.

The extract/grain Oregon Common ale has been in a hibernation state in the secondary carboy. After five days in a warmer area, bubbles are forming on top of the brew, the carboy stopper is moving, fermentation has started to revive!

Adding additional yeast, or fermentables provides too many possibilities for mishaps, bad taste, or disaster: exploding bottles. Leave it alone.