Imperial Stout Fermentation

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benchharp
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Imperial Stout Fermentation

Post by benchharp » Sun Oct 31, 2021 2:45 pm

Hi,

I usually do NEIPA's and am happy with my fermentation process on that. No need to comment on how NEIPA's are hoppy messes and not as hard to make as a brite beer, i like them, so i make them :roll: :D

My latest brew is a 9% imperial stout.

For my NEIPA's i would usually do both a diacetyl rest (ramp up 2 degrees toward the end fermentation) and a 2 day cold crash due to the amount of hops.

Would i need to do both or either on the Imperial stout or keep a consistent temperature throughout.

Any thoughts?

Many thanks in advance.

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Jocky
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Re: Imperial Stout Fermentation

Post by Jocky » Mon Nov 01, 2021 8:10 am

With that level of alcohol it doesn’t hurt to give the yeast a hand by bumping up the temperature when the fermentation is slowing down.

Most yeasts will be close to their alcohol tolerance at that point and the more complete you can get the fermentation the less creep you will have in the bottle as it ages (and you will want to give this a few months).
Ingredients: Water, Barley, Hops, Yeast, Seaweed, Blood, Sweat, The swim bladder of a sturgeon, My enemies tears, Scenes of mild peril, An otter's handbag and Riboflavin.

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Jocky
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Re: Imperial Stout Fermentation

Post by Jocky » Mon Nov 01, 2021 8:11 am

Oh, and I’d not be so bothered about a cold crash. There’s no hop matter to cash out and you’ll probably just want to let this ferment as long as possible rather than rush the yeast out of suspension.
Ingredients: Water, Barley, Hops, Yeast, Seaweed, Blood, Sweat, The swim bladder of a sturgeon, My enemies tears, Scenes of mild peril, An otter's handbag and Riboflavin.

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Re: Imperial Stout Fermentation

Post by f00b4r » Mon Nov 01, 2021 8:49 am

Check the alcohol tolerance of your planned strain and swap out as needed.
You will need a lot of healthy yeast cells, consider brewing a lower ABV beer (and/ora smaller batch) and the using that yeast cake, or part thereof, to ferment with on kegging/bottling day.

benchharp
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Re: Imperial Stout Fermentation

Post by benchharp » Thu Nov 04, 2021 12:17 am

Jocky wrote:
Mon Nov 01, 2021 8:11 am
Oh, and I’d not be so bothered about a cold crash. There’s no hop matter to cash out and you’ll probably just want to let this ferment as long as possible rather than rush the yeast out of suspension.
Thank you very much - I've realised that I forgot to add a Yeast Nutrient during the boil which is normal process. There was alot going on in the last 15 minutes and it slipped my mind. I imagine this could have helped to get some more robust results.

It's gone from 1.103 to 1.045 (on my float digital hydrometer - which tends to read higher than my refractometer reading)

Slow progress the last couple of days even with a temperature ramp.

I'll let it keep running for a few more days and see where we're at. 7.6 ABV isn't bad - Was aiming for 8.9.

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MashBag
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Re: Imperial Stout Fermentation

Post by MashBag » Thu Nov 04, 2021 8:50 am

General question.

Why is yeast nutrient added during boil?

benchharp
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Re: Imperial Stout Fermentation

Post by benchharp » Thu Nov 04, 2021 10:08 am

They're the instructions.

https://www.themaltmiller.co.uk/product ... -nutrient/

Homebrew notes: Add by breaking open 1 capsule and pouring the supplement in 10 minutes prior to the end of the boil. OR, if your fermentation does not require a boil, open the capsule and pour in the supplement before you pitch the yeast.

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Jocky
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Re: Imperial Stout Fermentation

Post by Jocky » Fri Nov 05, 2021 12:01 pm

I wouldn't worry about yeast nutrient too much. It's mainly needed for nutrient deficient worts or yeast that's been stored for a while (e.g. when making a starter). Much more important is making sure you've pitched enough yeast and having a good level of oxygenation.
Ingredients: Water, Barley, Hops, Yeast, Seaweed, Blood, Sweat, The swim bladder of a sturgeon, My enemies tears, Scenes of mild peril, An otter's handbag and Riboflavin.

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MashBag
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Re: Imperial Stout Fermentation

Post by MashBag » Fri Nov 05, 2021 8:03 pm

Bang on my thoughts Jocky

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floydmeddler
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Re: Imperial Stout Fermentation

Post by floydmeddler » Sat Nov 27, 2021 9:06 am

Hi Benchharp,

How is it going with this brew? Did you manage the F.G you were looking for?

Floyd

benchharp
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Re: Imperial Stout Fermentation

Post by benchharp » Sat Dec 18, 2021 4:04 pm

floydmeddler wrote:
Sat Nov 27, 2021 9:06 am
Hi Benchharp,

How is it going with this brew? Did you manage the F.G you were looking for?

Floyd
Hey, no it stopped short, finished at around 7-8%

I think i'd do a bit more research into the correct strain to use next time.

Either way it turned out magnificent and incredibly drinkable. A happy shortfall in this instance.

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Re: Imperial Stout Fermentation

Post by f00b4r » Sat Dec 18, 2021 6:04 pm

What yeast did you use to ferment with and how much of it?

benchharp
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Re: Imperial Stout Fermentation

Post by benchharp » Sun Dec 19, 2021 5:00 pm

f00b4r wrote:
Sat Dec 18, 2021 6:04 pm
What yeast did you use to ferment with and how much of it?
I do smaller batches than most - I have a 15l all in one.

I should have made a note of how much it yielded - I think it was around 12l into the fermentor.

I used 2 packets of dry yeast Safale S-04.

Used an aeration paddle to mkae sure that there was plenty of oxygen in there.
https://www.themaltmiller.co.uk/product ... on-paddle/

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Re: Imperial Stout Fermentation

Post by vacant » Sun Dec 19, 2021 5:48 pm

benchharp wrote:
Thu Nov 04, 2021 10:08 am
They're the instructions.

https://www.themaltmiller.co.uk/product ... -nutrient/

Homebrew notes: Add by breaking open 1 capsule and pouring the supplement in 10 minutes prior to the end of the boil. OR, if your fermentation does not require a boil, open the capsule and pour in the supplement before you pitch the yeast.
Though the blister pack itself states "dosage recommendation: 1 capsule per 1.7 gallons (4.26 litres)".

The only time I use a tiny bit of Wilko's yeast nutrient is when I'm stepping up slants or making a starter from Proper Job dregs.

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MashBag
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Re: Imperial Stout Fermentation

Post by MashBag » Thu Dec 23, 2021 6:56 am

benchharp wrote:
Sun Dec 19, 2021 5:00 pm
f00b4r wrote:
Sat Dec 18, 2021 6:04 pm
What yeast did you use to ferment with and how much of it?
I do smaller batches than most - I have a 15l all in one.

I should have made a note of how much it yielded - I think it was around 12l into the fermentor.

I used 2 packets of dry yeast Safale S-04.

Used an aeration paddle to mkae sure that there was plenty of oxygen in there.
https://www.themaltmiller.co.uk/product ... on-paddle/
Have I read that right? 2 packs In 12 lites?

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