Author Topic: Imperial Stout brewing questions  (Read 4387 times)

Offline alcaponejunior

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Imperial Stout brewing questions
« on: April 01, 2012, 10:51:31 AM »
You guys are so great in helping with recipes, I've got another one for ya, with questions about the process too.

Here is a sample recipe from brew builders for an imperial stout.  I'd like to try one sometime in the future (after proper recipe modifications, and also proper equipment upgrades).

Briess Traditional Dark Liquid Extract 15 lbs, 4.8 oz
Weyermann Rye Malt 1 lbs, 4 oz
Crisp Chocolate Malt 1 lbs, 0 oz
Briess 2 Row Caramel 120 1 lbs, 0 oz
Special B    0 lbs, 12 oz
Centennial Pellets 3 oz @ 60 mins
Centennial Pellets 2 oz @ 30 mins
Cascade Pellets    2 oz @ 15 mins
Oak Chips, Untoasted 1 ea
White Labs Super High Gravity Ale

targets:

OG 1.134 FG 1.027 IBU 67.9 SRM 60.51 ABV 14.02

I know dark extract isn't popular on this forum, but hopefully someone can 'splain me better why.  Which extracts should I use, how should I modify the specialty grains, should I use different grains, etc?

Also, I am assuming I would need at least a 6.5 gallon bucket with a blowoff tube, but would you recommend something different?  How do you handle beers like this that will have a lot of krausen?  Having an exploding bucket is definitely NOT an option!

Primary and secondary fermentations - how would you approach these?

Bottling and conditioning - what's the recommendation as to how to approach this?  Besides the obvious effects of aging, what considerations should I think about when it comes to aging a beer like this in bottles?  I tend to use 22oz bomber bottles, BTW, although I sometimes use 25oz and 12oz bottles too.  The main reason I use 22oz bottles is because you need fewer of them than 12oz, and I drink a lot of beers that come in bombers.

Oxygenation for such a strong beer - how to do it?

Also, what other changes to make in a recipe like this one in order to optimize my results?

I'd probably like the final ABV to be a bit lower, although not below 11.  Can I just use less extract?

I also want to assure maximum body and color.  I'd hate to brew an imperial stout with an ABV > 10 that wasn't thick and chewy, or didn't come out of the bottle looking like used diesel oil.  ::)  However, the target of 60.51 SRM on the sample recipe... how does that compare with your RIS recipes?

BTW there is no chance of my attempting to brew this one anytime soon, I have five or six others in the queue before this one could be attempted. 

Thanks for all insights!

Online garc_mall

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Re: Imperial Stout brewing questions
« Reply #1 on: April 01, 2012, 02:02:34 PM »
Im going to answer as many of these questions as I can, and leave the rest for others more experienced.

I know dark extract isn't popular on this forum, but hopefully someone can 'splain me better why.  Which extracts should I use, how should I modify the specialty grains, should I use different grains, etc?

The reason people (Including me) don't like dark extracts is that you can't control, and don't know what the brewmaster put into those extracts. You don't know the fermentability, you don't know if it was a munich base or a 2 row base, you don't know if they used chocolate, black patent, or both. Basically, all you know is that it is dark. With Extra light or light dme, there really isn't likely to be anything other than base malt, and maybe a bit of light crystal. Then you build your own beer, rather than guessing.

Also, I am assuming I would need at least a 6.5 gallon bucket with a blowoff tube, but would you recommend something different?  How do you handle beers like this that will have a lot of krausen?  Having an exploding bucket is definitely NOT an option!

I would use a 8 gallon bucket for this, That way everything stays inside the bucket.

Primary and secondary fermentations - how would you approach these?

Same way I would any other ale. Primary until it is done fermenting, then secondary if I am going to add any extra ingredients (coffee, other fermentables). It can do the long conditioning in the bottles, if you are going to bottle condition.

Bottling and conditioning - what's the recommendation as to how to approach this?  Besides the obvious effects of aging, what considerations should I think about when it comes to aging a beer like this in bottles?  I tend to use 22oz bomber bottles, BTW, although I sometimes use 25oz and 12oz bottles too.  The main reason I use 22oz bottles is because you need fewer of them than 12oz, and I drink a lot of beers that come in bombers.

Wait. Brew this like 4-6 months minimum before you are going to want drink it. It will take a while to mature, 22oz bottles are fine, but remember 22oz of 11% beer is a lot of alcohol.


Oxygenation for such a strong beer - how to do it?

Most places I have read use injected oxygen at pitching, and 12-24 hours after pitching to make sure the yeast have enough, and can grow enough.

Also, what other changes to make in a recipe like this one in order to optimize my results?

BIG Starter. I would do a mild or low gravity stout first, and then just toss this on the yeast cake.

I'd probably like the final ABV to be a bit lower, although not below 11.  Can I just use less extract?

Yes.

I also want to assure maximum body and color.  I'd hate to brew an imperial stout with an ABV > 10 that wasn't thick and chewy, or didn't come out of the bottle looking like used diesel oil.  ::)  However, the target of 60.51 SRM on the sample recipe... how does that compare with your RIS recipes?

This is why we recommend light extract plus specialty grains. You have a bit more control of the mouthfeel. I doubt you will have a problem though, with this high of gravity. I would worry more that the dark extract wouldn't be fermentable enough, and you would end up with a cloying beer, rather than an overly dry and thin beer.
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Fermenting: Flanders Red, Saison

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Re: Imperial Stout brewing questions
« Reply #2 on: April 01, 2012, 02:09:21 PM »

Oxygenation for such a strong beer - how to do it?

A Mix Stir is inexpensive and very effective.  I'm totally pleased with mine...

Life begins at 60.....1.060, that is!

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Offline alcaponejunior

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Re: Imperial Stout brewing questions
« Reply #3 on: April 01, 2012, 03:13:56 PM »
Thanks for the answers so quickly! 

Yeah I think I'm going to just get an eight gallon bucket anyway, because I need another bucket and for the price I might as well go with eight gallons.  That way any krausen issues are covered.

The stir bar looks great! 

I'm working my way up to RIS brewing territory...

Offline thomasbarnes

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Re: Imperial Stout brewing questions
« Reply #4 on: April 03, 2012, 02:34:54 AM »
Weyermann Rye Malt 1 lbs, 4 oz

This type of malt needs to be mashed, and might even need a protein rest. If you're steeping, you might have problems with haze and/or storage stability. It will definitely do great things for head formation and retention, however!

Centennial Pellets 3 oz @ 60 mins
Centennial Pellets 2 oz @ 30 mins
Cascade Pellets    2 oz @ 15 mins

That's a whole lotta hops. Definitely going for the American interpretation of the style. More to the point, all that hop bitter and citrusy hop flavor might very well clash with your dark malts. It's tricky to make a good hoppy dark beer, especially if it's big.

Oak Chips, Untoasted 1 ea

Don't need these, at least not yet. Let the beer ferment and condition, then decide if you want to oak it.

White Labs Super High Gravity Ale

This might be OK to finish off, but at lower OG you might want an ale yeast which throws more esters to help accentuate the sweet, chocolate notes. In any case, you'll need a big starter and lots of oxygen/aeration to keep your yeasties happy. You might also need to start off with a lower OG and "feed" the fermentation over a period of weeks by adding fresh wort or DME.

OG 1.134 FG 1.027 IBU 67.9 SRM 60.51 ABV 14.02

Not to discourage your experiments in rocket fuel production, but making a beer much above 10% is tricky and such beers can take years to come into peak condition. When young, they can be really hot, harsh and solventy tasting. Reduce your grist bill by 25% and you'll get a nice, authoritative RIS that's ready to drink in just a few weeks.

I know dark extract isn't popular on this forum, but hopefully someone can 'splain me better why.  Which extracts should I use, how should I modify the specialty grains, should I use different grains, etc?

Garc_mall basically got it right. You don't know what the dark stuff in the dark extract is. It could be relatively flavorless Sinamar or caramel color or it could be roast barley. Better to just use LME to substitute for base malt and steep your own dark grains for color and specialty malt character. It gives you better control over flavor, aroma and color.

Also, I am assuming I would need at least a 6.5 gallon bucket with a blowoff tube, but would you recommend something different?  How do you handle beers like this that will have a lot of krausen?  Having an exploding bucket is definitely NOT an option!

Big bucket with blow-off. Or split the batch into two different carboys/buckets. In either case, for primary fermentation you want a lot of head space. This is a style which produces a lot of krausen fast and there's lots of crud which can clog airlocks and blowoff tubes. My first attempt at a RIS got the name "Chernobyl #3" for exactly this reason!

Primary and secondary fermentations - how would you approach these?

Start off with a big starter (at least 1 quart, or perhaps 2 smack packs or dry yeast sachets) of American Ale or English Ale yeast. Aerate the hell out of it - probably 30 seconds worth of oxygen through a sintered airstone. Start fermentation on the cool side of the yeast's preferred temperature range, letting temperature rise by a couple of degrees once O.G. drops by at least 50% and krausen drops. Finish up on the warm side of the temperature range as gravity drops to desired F.G. The idea is that you're trying to limit production of esters, aldehydes, fusel alcohols and other fermentation byproducts.

For a really big beer, you might need to rack the beer, add a different strain of yeast and/or feed the fermentation to get desired ABV. This can take weeks.

Condition at least two weeks at cellar temperatures (~65 *F), perhaps cold condition for another 2-3 weeks at 32-55 *F to clarify and smooth out the flavor a bit. If necessary, rack and let it condition even longer, either at cellar or refrigerator temperatures.

Bottling and conditioning - what's the recommendation as to how to approach this?  Besides the obvious effects of aging, what considerations should I think about when it comes to aging a beer like this in bottles?

Make sure that you've really hit terminal gravity. There's a lot for yeasts to eat in a Russian Imperial Stout, so you don't want to bottle too soon - unless you like homebrew hand grenades.

If you had to cold condition or condition for an extended period of time, you might need to add a bit of new yeast at bottling along with the priming sugar. Due to the high ABV, it will take the yeast a long time to produce the proper levels of CO2.

If you have the technology, it might just be simpler to keg, force carbonate and bottle using a beer gun.

For long term storage, keep your beer as cold as possible without freezing it. Also, work to exclude oxygen from your beer at every stage of the production and packaging process. Blanket conditioning buckets with CO2, don't splash wort or raw beer. Get a good seal on your bottle caps and use oxygen-barrier caps. Dip the caps in wax to further exclude oxygen.

Can I just use less extract?

That's the easiest way to do it. Basically, use extract like you would use base malts if you're an all-grain brewer - for the bulk of the fermentables, but not so much for flavor and aroma.

I also want to assure maximum body and color.  I'd hate to brew an imperial stout with an ABV > 10 that wasn't thick and chewy, or didn't come out of the bottle looking like used diesel oil.  ::)  However, the target of 60.51 SRM on the sample recipe... how does that compare with your RIS recipes?

60 SRM is a bit on the light side. Adjust color using Carafa malt (basically, dehusked patent malt) or if you like your coffee and burnt grain character, add a bit (like no more than 1 oz.) of patent malt and/or roast barley. A little bit of the dark stuff goes a long, long way.

BTW there is no chance of my attempting to brew this one anytime soon, I have five or six others in the queue before this one could be attempted.

Get this one done soon, especially if you don't have great control over fermentation temperature. Big ales fermented during the summer can get way too warm and produce solventy, phenolic and excessively estery notes. If you're in a part of the world where it's already warm, you'll have to put it off until it gets cold again or use some method of cooling.

Offline alcaponejunior

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Re: Imperial Stout brewing questions
« Reply #5 on: April 04, 2012, 04:36:30 AM »
Hey thanks Thomas for yet another great answer to a long and detailed question! 

The reason this one won't be brewed soon is multi-fold. 

1.  I'm too new at this.  I need to increase my skills, improve my techniques, and upgrade my equipment a little.  I'm ordering an eight gallon bucket, which is what I'll undoubtedly brew my RIS (and upcoming barleywine) in.

2. Temperature control.  I don't have any right now.  Therefore I'm at the mercy of the temperature I can keep my closet, which is pretty steadily 68-70F.  This will change though, as I'll only be where I'm at until January, when I'll have a better place to brew.  I will probably try an imperial stout when I can better control the temperatures AND keep things cooler.

3. I hope to have a keg setup next year (hopefully two or three kegs).  The bottling questions were asked as a knowledge increasing measure, but I'm hoping not to have to bottle when I get to this beer.

I am keeping a bookmark to this thread however, and will tweak the recipe and run it past you guys again before it gets brewed!  Thanks man!

Offline bluesman

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Re: Imperial Stout brewing questions
« Reply #6 on: April 04, 2012, 06:35:01 AM »
One thing I would like to stress for a big beer like this is fermentation temperature control. A beer of this size will tend to really heat up during the first four days of ferment. You may want to consider a swamp cooler for this one. Keeping your temps under control will help produce a better beer IMO. I recommend keeping the beer temp under 70F.
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Offline alcaponejunior

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Re: Imperial Stout brewing questions
« Reply #7 on: April 04, 2012, 07:17:27 AM »
on the specialty malts, if I got rid of the rye malt, what could I replace it with which would keep the body and head good?  Here are some considerations I was thinking of for the specialty grain bill...

Briess 2 Row Caramel 120    
Crisp Chocolate Malt
Special B    
Weyermann De-Husked Carafa III
Briess Black Barley    

I definitely want to make sure that the body is thick and chewy, with good head and retention!  Now by the time I brew this I will certainly have the capability of doing a mash (not just steeping) with at least batch sparge capability.

I think I will cut the extracts as suggested and adjust amounts until I reach an ABV of about 10.0. 

And yes, I am going to make sure my fermentation temperatures are carefully controlled for this beer.  As I said, it won't be brewed for a while.  I'll brew it during the winter and use a heater blanket if it's too cold.  There is no way I could keep the temperatures low enough during the summer with my current circumstances and equipment.

I'm also working on a bigfoot barleywine clone, so I hope I can learn some things here that will also help there! 

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Re: Imperial Stout brewing questions
« Reply #8 on: April 04, 2012, 07:22:50 AM »
I really don't think that you have to worry about the body. you are not going to get a 1.134 wort down low enough to be anything but thick and chewy. If you will have the ability to do all grain by the time you brew this then you can certainly add some rye, flaked or malted. I don't think I would add crystal malt at all but if you do take it easy. There are some melanoidens in all wort barley wort and with this much barley there will be a lot of melanoidens. To ensure a goodly high FG I would mash around 152-155.

Batch Sparge v fly doesn't really limit you in any way so if you can get the ability to batch sparge you can do this all grain and just add some DME or LME to bump the gravity up as without a VERY big mashtun you will not be able to fit enough grain for a 5 gallon batch at that gravity.
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Offline alcaponejunior

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Re: Imperial Stout brewing questions
« Reply #9 on: April 04, 2012, 01:57:09 PM »
I should have at least the ability to batch sparge by the time I brew this one, so I'll keep that in mind.  Thanks!