ABV too high for yeast?

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johnnyc

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I posted earlier about a big Brown Ale I am making and had a few questions. First off it was a full 5 gallon boil, when I poured the cooled wort into the primary I had forgotten to close the spout after cleaning it and I lost a quart or 2 before catching the mistake. (Luckily I was in the garage not the kitchen)

Anyway I rehydrated dry yeast while cooling the wort and pitched it at the correct temp. The fermentation started well and 2 days later once the SG had dropped to roughly 1035 I added 8 oz of maple syrup dissolved in 1/2 cup of boiled water.

At that time the fermentation seems to hang, it sat at 1030~ for several days. I've read enough to let it go and just twisted the bucket to stir up the yeast w/o splashing a couple times a day for several days and then I started getting activity in the airlock again. I didn't bother opening the fermenter b/c I knew it had a while to go.

Its been 19 days and I checked it 2 days ago and the SG was around 1025. I tasted the hydro sample and while it tasted like a great beer, the alcohol bite was pronounced. I wonder if the alcohol is too high and killed the yeast. I'll post as much of the recipe below as I remember.

Steep 1/2 lbs Crystal Malt
6.6 lbs of LME
1 lb of Belgium candied sugar
8oz molassess
8oz light brown sugar
1 pk US-5

I forgot to check the damn OG but recipe called for 1070

I don't remember the hop schedule.

After the SG dropped to 1040-1030 I was supposed to add 8-10oz maple syrup.

I don't know the math to calculate the late sugar addition so I'm not sure what to expect right now.

Help anyone?
 
With an OG of 1.070 and a FG of 1.025, the alcohol content is around 5.8% ABV. With the addition of the maple syrup, I'm guessing you may have bumped that up to about 6-6.2% ABV. I can't find the alcohol tolerance of us-05, but I'd be really surprised if 6% was high enough to kill the yeast.

Beersmith estimates your OG around 1.065 and FG around 1.017, without the Maple Syrup addition. What temp have you been fermenting at?

Personally, I would let it sit a while longer, especially with the late addition of the MS, but I'm a noob, so take my advice with a grain of salt. :)
 
I've tried it keep it around 68-70 to hopefully keep it moving. I've had to move it around the house some to keep it at that temp, I left it in a basement closet overnight once and it dropped to 60-62 but I promptly moved it to a warmer area. I supposed the yeast could have gone dormant but wouldn't think a short dip would cause it.

In any case I don't plan to do anything but wait, but the recipe called for a final ABV of 9%. My thought is that since I lost the 1/2 gallon at the beginning and still added 8 oz of MS it may be even higher than that.
 
60-62 should have been fine, it's within the range of us-05. 9% seems a bit high for a beer with an OG of 1.070. With most beers finishing in the mid teen range, you would have to have an OG of around 1.085 to reach that ABV, or ferment out to around 1.000, which is awfully dry for a beer.
 
You can use the Fermcalc to figure out what the gravity adjustment might be, since adding sugar later also adjusts volume and can throw your numbers off.
 
You are well below the tolerance for any beer yeast. I think any yeast will get you to 10% ABV and most are good to 12+%.

I'm not sure how fermentable maple syrup is. It may be that that combined with your significant starting gravity that 1.025 is as low as it will go. Bring the temp up to about 70F and give it another swirl. 4 weeks in the primary would not be unreasonable for this beer. Give it some time.

Craig
 
how long should you wait for the fermentation? i'm in a similar situation. I have a beer that started out at 14o P and stopped at 5o P. I was estimating it would be around 2 or 3 P. When i pitched the yeast it was rocking and fermenting in a few hours. went strong for a day and then stopped at the 5 P gravity. I am going to rack it to a secondary so i can see whats going on (its in an opaque fermenter right now). But it was still really hazy when i took the last sample on tuesday. what do you think?

-nick
 
I think the reason it has that alcohol 'bite' is because its still really green. Trust me - let that beer condition in the bottles or keg and I can guarantee you that 'bite' will rather subside. I said the exact same things with my first brews - like Revvy says time makes beer better!
Good luck!
-Me
 
how long should you wait for the fermentation? i'm in a similar situation. I have a beer that started out at 14o P and stopped at 5o P. I was estimating it would be around 2 or 3 P. When i pitched the yeast it was rocking and fermenting in a few hours. went strong for a day and then stopped at the 5 P gravity. I am going to rack it to a secondary so i can see whats going on (its in an opaque fermenter right now). But it was still really hazy when i took the last sample on tuesday. what do you think?

-nick

How long has it been in the primary?

Airlock activity is NOT an indicator of fermentation being complete. Leave that sucker for another week or so THEN come back to it :) You arent hurting it by leaving it longer.
-Me
 
about 2 weeks in the primary, its an american ale style and i used safbrew s-33 dry yeast if that helps. i know air lock is not the fail safe way to show fermentation but the hydrometer has held at 5 plato for over a week.

-nick
 
The convention on this site is to use SG not Plato. Your call on whether you want to follow it. I tend to follow convention myself.

OP, As far as the FG goes on this beer you are pushing it with the molasses and maple syrups. Those will potentially add enough unfermentables to have you finish in the mid-20's. Not a problem for a brown really. Those can be pretty sweet.

As far as the alcohol bite. This has been covered fairly well but I will just say that with that much adjunct sugar you HAVE to expect strong hot alcohol for 4-8 weeks post bottling. You are at, what?, ~ 33% adjunct sugar? That is just going to take a long time to mellow out. Again, not a bad thing, but a reality.

Don't feel bad, I have a Belgian Dark in bottle for 5 weeks now that I will not even sip again for at least 8 weeks, the first bottle was SOOOO hot at 3 weeks I dumped half of it.
 
US-05 will handle at least 13% alcohol. I've personally gotten it up to 12.6% with no off flavors, it fermented like a beast and attenuated in 11 days. I'm guessing you could get it to 14% if you pitched a lot of yeast, stepped the gravity, and double aerated.

It sounds like you're stuck at 1.025. If you only pitched one package of yeast and didn't aerate really well, it's probably stuck, but only time and a hydrometer will tell if it's really done; it might just be finishing slowly. Your options at this point are to leave it alone, make a big starter adding some of your beer to it and pitching the starter at full krausen, or brew a small beer and then pitch this one on the yeast cake. Or you could even brew another batch and blend the two. Plenty of options.

At 1.025 I'd just leave it alone. It'll be sweet but it will still be good.
 
Ok, here's a question. I don't plan to bottle it soon, no problem waiting except my primary is also my bottling bucket and I have another beer I'd like to get in the bottle this weekend. If the fermentation is moving very slowly but still going if I rack it to a secondary would that risk completely stopping it? I need to get another bucket to avoid this issue in the future but for now...
 
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