Imperial Stout S.G. question

What went wrong? Was this supposed to happen? Should I throw it out? What do I do now?

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bredmakr
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Imperial Stout S.G. question

Post by bredmakr »

I racked an imerial stout Saturday afternoon O.G. 1.080 and the S.G. at racking was 1.036. The target final gravity is 1.024-1.028. Very little activity remains. Should I try to revive the yeast? The primary fermentation was at 68F and I've moved the carbouy to bring it up to 72-74F hoping that this would help. I did oxygenate the wort very well.
BillyBock
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Dextrinous Wort? Sluggish Yeast?

Post by BillyBock »

Could you post some details of your recipe? I suppose rousing the yeast wouldn't hurt. My guess for now: if you aerated the wort well and you had decent temps, I'd suspect the fermentability of the wort or yeast type/health. Was this an extract batch? What brand did you use? Some are more fermentable than others. If it was AG, what was your mash schedule? Again, maybe it was a dextrinous wort. What type of yeast did you use and how much did you pitch? Did you have an otherwise short lag time? Hope this gives some areas to think about. Looking forward to seeing your recipe. Let's crack this nut!

v/r
Bill
bredmakr
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extract with wyeast

Post by bredmakr »

this was an extract kit that I bought from MoreBeer.com. The imperial stout kit comes with 12 lbs light malt extract syrup, 1/2 lb crystal, 1/2 lb dry maltodextrine, 1/2 lb black roasted barley, 1/2 chocolate malt, and 1/3 black patent. I don't have the recipe in front of me so these totals could be +/- 2 oz. I boiled 6 gallons down to 5, chilled to 76F, gave it two 30-40 second bursts of 02 and pitched a 175 mL smack pack of WYEAST 1056. Probably not the best but I had this one in the fridge and yes I know this was a super high gravity (o.g. 1.080) and I should have pitched a starter. I had noticeable fermentation within 12 hours and full krausen at 20 hours. At that point I moved it to the basement to bring it down from 74F to 66F. It stayed there for the next five days until the krausen fell and activity pretty much came to a hault. I then racked it to secondary. At the time of my first post I had moved it back upstairs to try and raise the temp back up a few degrees and revive what ever yeast were still in suspension. The flavor is good but way too malty. Any and all advice is gratefully accepted.

Mike
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Underpitched new yeast.

Post by Brewer2001 »

Mike,

This has happend to me with a Stout. It was the first generation of Wyeast 1084 Irish Ale. The body and head was good initially but the batch did not age well (off flavors due to diacetyl conversion). This yeast is on its 9th generation and still going strong.

Assuming that your yeast was not too old and it was still viable here are some suggestions.
The addition of O2 was good. You should always build up your yeast to pitching 'volume' (which improves viability if all is right). New yeast may need a couple of generations to acheve their optumum fermentation ability, especially if they are pitched in high gravity wort(due to product inhibition they become lazy/over fed and do not multiply). Try to schedule your brews so that you are able to use repitched yeast. Bring your pitch volume up to a quart for pitching.

If you still want to drop the SG you could make a PINT of starter and pitch it into your secondary at fermentation temperature. You may have to 'crash' chill and rerack to clear the ale because of the active fermentation in the secondary.

Good luck and Good brewing....

Tom
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Relax...

Post by Monkey Man »

I too brew big beers- some as high as 1.131. Give it time. If I read your post right it has only fermented for five days. It will come down some in the secondary. Relax. Your yeast is in the final stretch. Running the last lap. Provided it don't pull a Dale Ernhardt you'll probably be okay.
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