Stuck or Finished? What should I try?

[rxp]

I brewed an RIS three weeks ago (https://www.homebrewtalk.com/f12/please-critique-my-imperial-stout-263404/index2.html#post3428261), but in the past week the gravity hasn't budged from 1.028 despite gentle rousing and words of encouragement. The tasted samples are beyond my expectations, but still slightly on the sweet side. I was initially aiming for a FG around 1.018, but got more efficiency than expected and had hoped to hit 1.020 for about 81% AA. In my step-up batch, WLP007 yielded ~71% attenuation and this time around it's ~73%; this is definitely within but on the low side of the advertised range, particularly for a strain for which brewers often get north of 80%.

I understand that I may have a large number of unfermentables, especially given that my boil ran for about 2 hours and 45 minutes in order to bring my volumes down. If that is the case, then I can certainly adapt to having brewed a sweet stout and be happy with the results, particularly knowing that carbonation will take some of the edge off.

On the other hand, if I can squeeze out some more points (maybe 10 or so), I'd really like to do that. I have some WLP550 cultured from previous batches that I'm considering using due to its high alcohol tolerance and my experiences of reaching 80% - 85% attenuation with it. This yeast should also be fairly clean below 67*F and I'd be maintaining 65*F.

Given this, is there a good reason I shouldn't pitch some wlp550? Otherwise, I have some US 05 packets on hand or would be up for buying a vial of something else.

Any recommendations?

 

[Kaz]

When you rouse, have you tried warming it up a few degrees? If you fermented at 65F, that's the bottom of the yeast's temp range and being highly flocculent, it may have settled out. Are you sure you hit your mash temp of 151F? Just a couple things I thought of.

 

[Lucky_Chicken]

I would doubt you would have much luck pitching yeast into a wort with little fermentables left in it. You could try warming it up to "wake up" the yeast again to finish a little higher if not then enjoy it for what it is, sounds like its pretty good just not what you were going for.

 

[Arkador]

there is nothing wrong with a malty RIS. Definatley no more yeast. at this point I would just cold crash, and keg it.

I am a fan of enjoying what I get, and improving on what was missed on my next try. I am sure you made a good beer, but trying to jack with it at this stage of the game can often cause more harm than good.

 

[TzeentchPlayer]

Did you hit your intended OG or did you go over? I added some unfermentables to my AHS Steamroller Stout and missed a number somewhere. I thought I was stuck at the dreaded 1.034 but it turns out I just can't add decimals.

 

[rxp]

Thanks for the responses!

Did you hit your intended OG or did you go over? I added some unfermentables to my AHS Steamroller Stout and missed a number somewhere. I thought I was stuck at the dreaded 1.034 but it turns out I just can't add decimals.

I went over. I was aiming for around 1.094 but must've had less grain absorption than expected and ended up with an extra gallon to boil off, taking my OG to 1.104.

When you rouse, have you tried warming it up a few degrees? If you fermented at 65F, that's the bottom of the yeast's temp range and being highly flocculent, it may have settled out. Are you sure you hit your mash temp of 151F? Just a couple things I thought of.

Not really; given my previous results and knowing that 007 was highly flocculant, I was expecting my rousing to be mostly preventative. I hadn't expected the yeast to not be doing anything at all the entire time. The temperature during the past week (~67*F) was the same as the week prior during which it went from 1.045 to 1.028, so I assumed it would be warm enough to continue. I did hit 151*F, I actually was aiming a degree or two higher...I'm glad I missed.

there is nothing wrong with a malty RIS. Definatley no more yeast. at this point I would just cold crash, and keg it.

I am a fan of enjoying what I get, and improving on what was missed on my next try. I am sure you made a good beer, but trying to jack with it at this stage of the game can often cause more harm than good.

Noted. My only reservation is that I wanted a stout with body and had already built "malty" into the recipe -- I'm a little beyond that now. I do have a tendency to screw with things a bit too much, so I might resist the urge to fuss with any additions and take your advice to keep something that is ninety percent of what I wanted.

I would doubt you would have much luck pitching yeast into a wort with little fermentables left in it. You could try warming it up to "wake up" the yeast again to finish a little higher if not then enjoy it for what it is, sounds like its pretty good just not what you were going for.

Okay, thanks. I think I'm leaning the warming route now. I've not traditionally had much luck with that and the current temps are the same as the temps it was using for the last 17 points, but I won't have to worry too much about wrecking it either.

 

[passedpawn]

Probably won't move, even with new yeast. Still, might as well try the new yeast. Something that definitely will work to get that down is in the following link. However, I suggest you thoroughly read and heed the warnings there. It will work. Just give it plenty of time before you bottle.

https://www.homebrewtalk.com/f163/escape-stuck-fermentation-mountain-ae-rescue-212926/

 

[Sacdan]

I'll bet it tastes fantastic in about 6 months to a year. Remember that it is still green at only 3 weeks. Keg it if you can and leave it at room temp. My RIS was okay in the beginning. It tastes excellent now.

 

[jigidyjim]

I'm in the same situation - stuck at 1.030 was hoping for 1.020. I've spent a bunch of time reading on here, and basically it seems like the only choices are a) try to wake the yeast up by turning up the temp and swirling the carboy or b) rack the beer on to a yeast cake from another brew.

(a) didn't work for me, and (b) isn't an option, so I'm bottling this weekend...