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General Category => Yeast and Fermentation => Topic started by: etbrew on January 25, 2010, 02:20:46 pm

Title: Yeast alcohol tolerance concern
Post by: etbrew on January 25, 2010, 02:20:46 pm
I'm planning on brewing an imperial stout this week.  I'm estimating the OG to be approx 1.110+ and I'm shooting for a FG of the 1.022+ range.  I have made my starter with Wyeast 1056 and then realized the alcohol tolerance for this yeast is around 10% ABV This beer will be close to that level and I'm worried it won't ferment completely, or it get's most of the job done, look like it has finished fermenting, I bottle it, and I get no carbonation.

So I have a a couple questions:
Will this yeast be able to handle the alcohol level?
If not, do any of you have a suggestion for another yeast strain I should use?  (my fermentation temp will be around 66 F)
Is there a way I could tell if I killed the yeast before bottling?

-Eric
Title: Re: Yeast alcohol tolerance concern
Post by: denny on January 25, 2010, 02:35:46 pm
I've used that yeast for beers up to 12% and it worked fine.  I'd recommend brewing a mid 40s gravity batch first and using the entire slurry from that.  You will almost certainly need to add more yeast at bottling.
Title: Re: Yeast alcohol tolerance concern
Post by: etbrew on January 25, 2010, 03:56:36 pm
I've used that yeast for beers up to 12% and it worked fine.  I'd recommend brewing a mid 40s gravity batch first and using the entire slurry from that.  You will almost certainly need to add more yeast at bottling.

Thanks.

I do have about 2 cups of slurry from a batch of porter but there's a chance it could be contaminated (it started out as 4 cups but I dropped the jar on the floor and sprayed yeast all over my kitchen...it was great  :-[ )

So in the absence of a batch of slurry what are your thoughts?  My plan was to make a 2 quart starter today, then add another quart of starter wort to the original to give me a gallon starter.

This would be the first time I've added yeast at bottling.  How much yeast should I add at bottling?
 
Title: Re: Yeast alcohol tolerance concern
Post by: skyler on February 02, 2010, 12:05:16 pm
I'd recommend brewing a mid 40s gravity batch first and using the entire slurry from that.

So in the absence of a batch of slurry what are your thoughts?  My plan was to make a 2 quart starter today, then add another quart of starter wort to the original to give me a gallon starter.

 How much yeast should I add at bottling?
 

What he is saying is that you should brew a whole mid-40s (1.043-1.047) beer. You could do something along the lines of a K├Âlsch, a dry stout, or even an American Wheat beer.... Then pitch your Imperial Stout on top of that slurry. I would even go as far as brewing something in the low 50s, like a 1.052 pale ale, before pitching the full slurry.

As for the yeast to add at bottling, just pitch a pack (or maybe 2 in this case) of US-05 a day or two before you bottle. Some people recommend bottling with Champagne yeast in a beer that big, but I have never done that.
Title: Re: Yeast alcohol tolerance concern
Post by: a10t2 on February 02, 2010, 12:57:23 pm
So in the absence of a batch of slurry what are your thoughts?  My plan was to make a 2 quart starter today, then add another quart of starter wort to the original to give me a gallon starter.

That won't give you the cell count of a gallon starter, or even a 3 quart starter. You need to increase the volume at each stage to get substantial growth.

For a 1.110 beer, you need about 400B cells. I'm guessing you're limited by the use of a gallon jug? In that case make a 1 L starter, let it ferment out, chill and decant, then add another 2.5 L of wort. Shake up both stages as much as possible. Again, I'm assuming you don't have a stir plate.

To add yeast at bottling, just use the cheapest dry yeast you can find (probably Nottingham), rehydrate about 1/4 of the packet, and add it to the bottling bucket. You don't need much yeast to carbonate.
Title: Re: Yeast alcohol tolerance concern
Post by: Kaiser on February 02, 2010, 01:45:48 pm
Alcohol tolerance is partly genetic (i.e. dependent on the strain) but for the most part a function of the yeast health and the yeast amount. Both aspects should be considered. The greater yeast pitching rate will limit yeast growth and with it the thinning of the cell walls (simply speaking). But to be alcohol tolerant yeast needs to have strong cell walls to start with which comes from having sufficiency oxygen during their growth.

I second the suggestion that brewing a low gravity starter beer may be a better way to get enough yeast that making a large starter.

Kai

Title: Re: Yeast alcohol tolerance concern
Post by: etbrew on February 04, 2010, 02:50:45 pm
Thanks for all the advice. 
I ended up making a lower gravity stout (1.086) on the 30th before you folks posted and made the starter like I had mentioned in the earlier post.  We'll see how it comes out. 

 


Title: Re: Yeast alcohol tolerance concern
Post by: Hokerer on February 04, 2010, 07:48:34 pm
a lower gravity stout (1.086)

1.086 is "lower gravity"? Yikes!
Title: Re: Yeast alcohol tolerance concern
Post by: mikeypedersen on February 05, 2010, 08:31:00 am
a lower gravity stout (1.086)

1.086 is "lower gravity"? Yikes!
I think he means compared to the 1.110+ that he was talking about in the original post.
Title: Re: Yeast alcohol tolerance concern
Post by: etbrew on February 06, 2010, 06:56:19 pm
a lower gravity stout (1.086)

1.086 is "lower gravity"? Yikes!
I think he means compared to the 1.110+ that he was talking about in the original post.
Yes, compared to the 1.110  :)
Title: Re: Yeast alcohol tolerance concern
Post by: Kaiser on February 07, 2010, 09:43:26 am
Yes it might be lower gravity but I still think that a 1030-1050 beer would have made a better growth medium for the yeast.

Kai