Re-kindling a stuck fermentation in carbonated beer

[stepcg6]

Hello everyone!

I had a dunkelweizen that didn't finish all the way. FG Was 1.020.

I was stupid and just went ahead and kegged it, carbed it up at 16 psi, and started drinking, hoping it wouldn't be a sugar bomb. It is.

I'd like to fix this.

My plan is to take the beer off tap, bleed it, and get it back to room temperature. I'm going to siphon to a carboy and pitch another vial of hef yeast to knock down that last bit of gravity, hopefully down to 1.040 or below.

My question to you all: will the fact that this is carbonated beer be a problem for restarting fermentation? I figure that much of the CO2 will leave solution as it warms to room temp and gets siphoned off, but this was at one point fully carbonated beer.

Anyone see any issues here?

Thanks in advance!

 

[Stealthcruiser]

I'll be watchin'!

 

[brew_ny]

subed

 

[flars]

Was this all grain or extract. Mashing grains at high temps will create unfermentable sugars. Your beer may be at FG for the amount of fermentable sugars present in the wort.

 

[stepcg6]

All grain, I can post the recipe:


STATS:
Original Gravity: 1.058
TARGET Final Gravity: 1.014
ABV (standard): 5.79%
IBU (tinseth): 16.67
SRM (morey): 11.85

FERMENTABLES:
6 lb - Belgian - Pilsner (45.3%)
6 lb - German - Wheat Malt (45.3%)
2 oz - United Kingdom - Chocolate (0.9%)
9 oz - German - Munich Dark (4.2%)
9 oz - Belgian - CaraMunich (4.2%)

HOPS:
1 oz - Tettnanger, Type: Pellet, AA: 4.5, Use: Boil for 60 min, IBU: 16.67

I always make 1.5L yeast starters on a stir plate with ferm temps in the high 60s.

I've never had a beer stall out like this, so I can't think of what the issue was besides just not finishing. I can't imagine a lack of unfermentables leaving an FG of 1.020 but please correct me if that thinking is incorrect.

Mash temp was 153F

 

[j1n]

It will prob work if you have enough yeast. I had a stuck fermentation with my Dead guy clone and it stuck at 1.021. fermented it at 60*F. i brought it up to room temp and it went all the way down to 1.010 (too much attenuation though). my mash temp was also 153. There's a lot of co2 in solution when its fermenting so i dont see why that would be an issue.

 

[stepcg6]

Other suggestions/input/DON'TDOITYOUIDIOT are welcome, but I'll deliver my results.

Plan on transferring and pitching tomorrow, then giving it about a week.

 

[flars]

Before you go all out, add some yeast to a sample of the beer. Check SG in a week for fermentation activity.

 

[trentm]

If you try it, I would suggest pitching a well aerated starter at high krausen. This will provide healthy yeast that won't have to go through lag phase.

 

[stepcg6]

UPDATE:

On the way to the homebrew shop I had an epiphany: Most of the esters and phenolics of the yeast had already formed in the past 3 weeks of fermentation...why not pitch a more alcohol resistant, clean yeast to help tackle the remaining sugars?

A buddy of mine at the shop suggested the dry yeast Nottingham Ale for the job, said it helped finish a trippel of his that stalled at 1022.

Most of the plan went off without a hitch. The single moment of contention was the keg blowing up all over my bathroom. It seems as though bleeding the keg a couple times a day did not release all the co2 of a fully carbed beer, and when moving the keg and popping the top, it started foaming out the top.

Luckily, I kept my cool, pitched my rehydrated yeast and syphoned right through the bubbling into a 5 gallon carboy. When all was said and done, there was, and still is, a lot of activity in there. I'm sure a lot of it is co2 already in solution leaving, but lets hope a good amount of it is the fresh yeast eating the remaining sugars.

I will post further results in one week when I take a gravity reading and hopefully re-keg this beer.

Thanks for the suggestions everyone!

 

[stepcg6]

UPDATE:

I was in fact able to get the beer down to about 1.014, have kegged it, carbing up now and we will see how it tastes!

 

[brew_ny]

UPDATE:

I was in fact able to get the beer down to about 1.014, have kegged it, carbing up now and we will see how it tastes!

thanks for the update

 

[bredle]

and how does it taste now? I have the same issue with my brown ale. Kegged without a hydro reading because I broke my hydro (typical). I have it carbed and its VERY sweet (likely stuck in the 20's).

So - should I siphon to a carboy and repitch (maybe Notti) like you did? Did it turn out good in the end?