Am I asking too much of my US05?

[Publius]

I brewed a 1 gallon batch of barleywine 3 weeks ago, OG 1.125. Pitched a packet of US05, and it churned along steadily at about 62 degrees for the first 10 days or so. When the krausen subsided I raised the temp to 67 and the yeast became active.again for another few days. The gravity seems to have settled now at 1.030, which I believe puts me at about 75% attenuation and 12.5% ABV. So here is my dilemma:

I know I'm right at the limits of my yeast in terms of alcohol tolerance and attenuation, but I like where my beer is right now. The body and residual sweetness are right in line with what I was shooting for. Therefore, I would prefer not to add a higher alcohol tolerance yeast to bottle carb if I can avoid it. Do you think I can get away with just adding some priming sugar and hoping those yeasties are down for one last meal before the alcohol kills em off completely? I was thinking about maybe running a test by drawing out a small amount of wort into a cup, adding some table sugar, and watching for any signs of activity. Does that seem valid?

If I do try to bottle carb with just my existing yeast, would it be prudent to bottle now, as opposed to keeping it in primary longer or racking to secondary? I realize it would probably be better overall for the beer if it were to sit on that yeast cake for awhile longer, but if yeast viability is my foremost concern I feel like I should go ahead and prime/bottle?

Any thoughts / advice will be much appreciated!

 

[eastoak]

adding yeast for carbing will not affect the body or sweetness of the beer since it's limited by the amount of priming sugar you add to the batch. if it was my beer i would just go with it as is, no additional yeast, it's unlikely that all of the yeast will be dead.

 

[Chadwick]

I made a barleywine with these same numbers about a year ago. I also just used a single pack of US-05. I got my gravity down to 1.022 before I bottled.

I suggest rousing the yeast and warming it up into the low 70's. I gave my beer 5 weeks in the primary before bottling. I skipped the secondary completely. The gravity kept falling up into the 4th week. Although very slowly. I didn't add any priming yeast when I bottled. I primed it for medium-low carbonation and I ended up with very very high carbonation after 8 weeks of bottle conditioning. My final ABV was almost 15%. US-05 is a beast of a yeast.

 

[Publius]

Thanks guys. I will try bringing the temp up and will let it sit in primary for another couple weeks before bottling.

 

[Publius]

Update: after raising the temp up to low 70s, gravity dropped another 8 points and is now at 1.022. I went ahead and racked it to secondary, as I was anxious to free up my primary fermentor. Before cleaning out the yeast cake and the minute amount of wort sitting on top of the cake, I dumped a few tablespoons of table sugar into the fermentor. Intent was to see if I could detect any activity that would give me some reassurance that I still had some viability left in my yeast. Within hours, I was seeing significant bubbling/churning! US05 is amazing stuff...seems to be more than ready to carb my bottles for me, even at 13.5% ABV!