How much should I care about not breaching 12% ABV?

It seems like 12% is the max you see listed for any yeast strain. I'm formulating a simple English barley wine and I'll be using WLP007. I have fair experience with it, although I don't think ever over 9% to date. My average attenuation with it is about 82%. White Labs doesn't give numbers for alcohol tolerance, but I know that this stain has a good, high tolerance.

I'm planning on a nice long boil, probably 120 to 150 minutes. I keep track of a lot of my brewing stats since I jumped into AG this year. My boil-off rate jumps around a bit, and I can't nail down with great confidence that my boil-off rate will be X gal/hr. And, if my end volume strays one way or the other, my recipe can easily jump from 11% to 12.75%.

I would like to push this decidedly over 10%. Do I need to worry about going a bit over 12%, per calculations? Might my yeast give up along the way?

 

I would just go for it and see what happens. I would make a yeast starter, and make sure the wort is very well aerated before adding it. Use yeast nutrient, just in case, and it will probably work out.

Revisit this thread when you find out the FG and alcohol level, and let us know what happened. We could use your data. Good luck!

 

I've gotten the less tolerant Wy1318 to nearly 12% so WLP007 should be able to surpass 12%. pitch a ton, mash low-ish, oxygenate well, & use some nutrient to help it out. personally i'd make a smaller beer & just use the cake from that.

 

I was surprised to find that there isn't really a wall. It's more of an effect over time. Yeast can function in a very high ABV environment for longer than you may think.

If you are concerned you can re-pitch the yeast when you prime.

Details here:
http://woodlandbrew.blogspot.com/2013/01/abv-effects-on-yeast.html

 

Most yeast can be driven well past their listed attenuation and alcohol tolerance rates by treating them correctly. Some things I've found that really help are:

• Mashing low - 146F to 148F
• Oxygenating (not aerating) plenty at pitching time, and again prior to the start of active fermentation
• Pitching at a rate that might be considered 'overpitching' based on the various yeast calculators
• Adding simple sugars one or more times as fermentation starts to wind down

As others have said, nutrients and re-pitching a neutral ale yeast if bottle conditioning are good ideas too.

 

• I do plan to mash low, but also long. I mash in a cooler, so I'll probably aim for 150F and expect it to drop from there over 90 minutes.
• Unfortunately I can't oxygenate. I'll be aerating with a power drill.
• I'll be making a starter with multiple step-ups. How much should I "overpitch"? I know on yeastcalc.com, which is what I use, there's now a couple different stir plate rates of growth assumption available. I usually use the higher growth rate assumption, but I could definitely use the more conserve in my calculations as a start.
• I don't think I'll add sugars during fermentation, but definitely will use yeast nutrient.
• I plan on bulk aging in secondary for at least 8 months, so I plan on re-pitching at bottling regardless.

 

There's a great section in the first few chapters of the book "Yeast" about getting beers up in the 15% range. It involves all the things mentioned here already including multiple simple sugar additions. What hasn't been mentioned is it recommends fermenting the first 3 days I think with whatever character strain you want, and then pitching something clean and agressive like US-05 with the sugar additions. Pretty crazy stuff...

 

Oh, I was also thinking, should I change the temp schedule to help this along? With WLP007, I usually pitch around 65F, keep it at cooling-cut-in at 65F with a 1 degree diff (i.e. 63-65F) for the first 48-hours-ish, basically until visible signs of fermentation slowing, and then let it rise as it will closer to ambient 67-68ish. Should I start higher off the bat to gain momentum? Or, should I pitch at 65F, but start ramping during active Krausen?

 

i definitely wouldn't start higher off than usual, if anything i'd start lower. temps get out of hand quick in big beers

 

It's been a while since I racked to secondary, but I thought I'd post back. This ended up at an OG=1.121 and FG=1.029. Those numbers alone would put me just over 12% ABV. However, I pitched a fair amount of un-decanted starter, and after adjusting for dilution my actual ABV is more like 11.3%.