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General Category => Yeast and Fermentation => Topic started by: rhcpfan4002 on June 01, 2013, 06:58:17 PM

Title: First Stuck Fermentation
Post by: rhcpfan4002 on June 01, 2013, 06:58:17 PM
So a friend and I made an American barley wine with an OG of .095. We pitched 2 packs of Wyeast 1332 in a 1 liter starter and 4 days later we poured in a vial of wlp545. During this time we kept the temperature at 60ish for 3 weeks and then raised the temperature to 70F for one week then placed the beer into a secondary. Once we moved to the secondary we took another hydrometer reading and only had a drop to .047. I was hoping for at least .030. We were planing on doing the following. Crash the beer to 50F for two weeks to get everything out of suspension and then raise the temperature back to 60 and place in another starter made from 1 vial of wlp545 along with yeast nutrients. After a week do another diacetyl rest and then bottle. Good idea?
Title: Re: First Stuck Fermentation
Post by: malzig on June 02, 2013, 05:43:12 AM
Your best chance of resuming fermentation is probably to make a fresh starter with a vial or pack of yeast and pitch the starter while it is highly active.  It is probably going to be tough, though.

It looks like you accidentally gave us a textbook example of the potential effect of underpitching yeast.  Unfortunately, that becomes more significant when making such a high gravity beer.  Not to say that's what happened, since I have no way of knowing the fermentability of the wort, but it is a distinct possibility.

Ideal pitch for an ale:
0.85e9 cells/LxP x 19 L x 23 P  = 371e9 cells

I've found that a vial of yeast pitched into a half-liter will grow about 1.25-fold, so you probably pitched ~225e9-250e9 cells, or about 1/2 - 2/3 of the recommended cell density.

For a high gravity beer like this, brewers often use a higher pitch rate, maybe half-again higher, which could put you down near 1/3 the recommended amount of yeast.

Edit: I didn't notice the third vial of yeast, but seeing the mash temperature you may have found the real culprit.
Title: First Stuck Fermentation
Post by: duboman on June 02, 2013, 06:03:51 AM
A recipe and mash temp would help. You may have had too much specialty grain or too high a mash temp creating a much less ferment able wort

Under pitching and poor aeration are also a concern.

Some additional info would help
Title: Re: First Stuck Fermentation
Post by: rhcpfan4002 on June 02, 2013, 09:48:21 AM
Thanks everyone, If it will help here is the recipe and mash temps. We used an aeration stone with oxygen as well.

Biscuit Malt 1.1 lb
pale malt 22.4 lb
crystal 90l 1.1 lb
crystal 60l .4 lb

cascade 2 oz at 60 min
amarillo .5 at 15 min
cascade .6 at 15
amarillo .5 at 5
cascade .6 at 5

Yeast two smack packs of wyeast 1332 and one vial of wlp545 4 days later

Mash Schedule:
sacc 158F for 120 min
mash out 167F
sparge 167F
Title: Re: First Stuck Fermentation
Post by: euge on June 02, 2013, 10:17:15 AM
I'd say 158F mash temp is a tad bit on the high side for an American BW. Any Barleywine for that matter...
Title: Re: First Stuck Fermentation
Post by: malzig on June 02, 2013, 11:17:12 AM
I'd say 158F mash temp is a tad bit on the high side for an American BW. Any Barleywine for that matter...
Yeah, I probably wouldn't waste more yeast on trying to get the gravity lower, since it might just be done.  You can try giving it a little more time and see if it is dropping at all, but more yeast isn't going to do much.

Edit: Sonething more like 149F might have been a beter choice.
Title: Re: First Stuck Fermentation
Post by: jeffy on June 02, 2013, 11:29:25 AM
I'd say 158F mash temp is a tad bit on the high side for an American BW. Any Barleywine for that matter...
Yeah, I probably wouldn't waste more yeast on trying to get the gravity lower, since it might just be done.  You can try giving it a little more time and see if it is dropping at all, but more yeast isn't going to do much.

Edit: Sonething more like 149F might have been a beter choice.
I agree with this.  For really big beers I usually shoot for lower mash temps to promote more fermentation.
Title: First Stuck Fermentation
Post by: duboman on June 02, 2013, 12:04:06 PM

I'd say 158F mash temp is a tad bit on the high side for an American BW. Any Barleywine for that matter...
Yeah, I probably wouldn't waste more yeast on trying to get the gravity lower, since it might just be done.  You can try giving it a little more time and see if it is dropping at all, but more yeast isn't going to do much.

Edit: Sonething more like 149F might have been a beter choice.
I agree with this.  For really big beers I usually shoot for lower mash temps to promote more fermentation.

Definitely!
Title: Re: First Stuck Fermentation
Post by: rhcpfan4002 on June 02, 2013, 04:15:27 PM
Thanks everyone,
I'll discuss with my friend what we should do. I seriously never had this happen before. I always hit the  attenuation of what the yeast is suppose to hit. Then again, except for my tripel, all my beers are under .06. I am taking it that if you make beers with a greater o.g. you need to think differently than with a beer with a smaller o.g.
Title: Re: First Stuck Fermentation
Post by: malzig on June 03, 2013, 04:23:54 AM
158°F is a high mash temperature, even for a 1.060 beer, unless you want it to finish thick.  I sometimes use mash temperatures that high for beers down in the 1.035-1.040 range.  I'll occasionally use 155-156°F for a 1.048 beer.  They are noticeably full bodied and lower the attenuation by about 10% from a beer mashed down near 149°F.
Title: Re: First Stuck Fermentation
Post by: garc_mall on June 03, 2013, 08:32:10 AM
I agree with everything in here.

here is my 2 cents to add.

Remember, Big beers will finish higher than small beers by nature. This difference is magnified by mash temperature. If I am doing a low gravity mild (1.038-1.042), I mash at 162, and get about 50% AA. With my Scotch ale (1.080ish), I mashed at 152, and got about 70% AA. When I mash my APA (1.055) at 152, I get about 75-80% AA.

Some of this is yeast strain dependent, some is recipe dependent (my APA has 0 crystal), but a huge part of the difference is mash temperature.

regardless, this is a good learning experience. I would taste the beer. It might taste ok. If it is too sweet, I would not recommend throwing in more yeast (Sacc), because I think you are pretty close to the final gravity you are going to get. You might be able to get a brett strain to bring that down a bit further before the alcohol takes them out.
Title: Re: First Stuck Fermentation
Post by: Jo Diesel on June 03, 2013, 08:55:47 AM
Would it help any to raise the temp up to about 70 to get it to ferment out a little more? Don't know just asking.
Title: Re: First Stuck Fermentation
Post by: Jimmy K on June 03, 2013, 08:58:54 AM
You might get a few more points by raising the temperature and pitching an active yeast starter. If it goes nowhere, at least you can be confident bottling it.  If it's sweet tasting, bottle and stick it in a corner for a few years.
Title: Re: First Stuck Fermentation
Post by: ynotbrusum on June 04, 2013, 11:26:13 AM
I had a BW that was sickly sweet (extract batch of NB's Lord Fatbottom, so not a mash issue) - I bottled and stored it still and it improved over time (2 years).  I blend it with a simple ale (just a little) once in a while for serving and it comes out fine.
Title: Re: First Stuck Fermentation
Post by: euge on June 04, 2013, 03:29:43 PM
I had a BW that was sickly sweet (extract batch of NB's Lord Fatbottom, so not a mash issue) - I bottled and stored it still and it improved over time (2 years).  I blend it with a simple ale (just a little) once in a while for serving and it comes out fine.

+ Eleventy billion! There is nothing wrong with blending. In fact, you often end up with an excellent beer that could not have been brewed singly.
Title: Re: First Stuck Fermentation
Post by: svejk on June 04, 2013, 03:46:19 PM
One thing I will add to this conversation is that you could try a fast-ferment test.  Take a sample of the beer (at least enough to fill your hydrometer tube) and pitch an entire pack of Nottingham in it.  Since you're not drinking the sample and not worried about oxidation, shake the crap out of it and leave it at room temperature for a week or so.  Check the gravity again and if it hasn't moved with that much yeast, then you can be 100% sure that there aren't any remaining fermentables in the beer and it only cost you a few bucks.

On the other hand, if you do find that it fermented drier, then there is hope.  In this situation, I have tried just about every option out there (multiple packs of yeast, starters, etc.) and my only success came when I pitched a huge slug of healthy slurry from a local brewery or brewpub - on the order of a quart or more of a workhorse yeast like 1056.  Sure, it's overpitching, but I was able to take one of my larger (1.130+) beers down another 15 points using this method.

I also agree with the others who say you should set this aside.  Some beers that were cloyingly sweet when they were young turned into great beers with a few years on them.