My first Imperial Stout

[foxbat]

Got up early doors this morning to get a 12 litre BIAB batch of Imperial Stout on the go. Hoping to be done and dusted before the England game at 1pm. The idea's to get this one bottled and aged for Christmas. This was my first big dark beer so I'm totally out of my comfort zone (a good thing) and had to do a fair bit of planning to get things where they needed to be.

Here's the abbreviated recipe for a guesstimate of 70% efficiency, that's 10% reduced from what I normally get since everyone says to lower your expectations for these types of beers.

Est. OG: 1.090
Est. IBU: 84

64% Pale malt
20% Munich malt
7% Roast barley
4% Crystal 240 EBC
3% Low colour chocolate malt
2% Special B 380 EBC

11g Polaris 18% AA 60 mins
11g Polaris 18% AA 30 mins
11g Polaris 18% AA 15 mins

Crushed the grains with the grinder set to 32 mils:

Mashed at 66C for 90 minutes giving it a quick stir at 45 mins because it was quite thick. Dunk sparged the bag for 10 minutes with 6 litres.

Pre-boil gravity was 1.070 for an 82% mash efficiency, easily beating the estimate of 1.065. Well pleased with my mash efficiency on this one.

Got the boil on nice and quick with this smaller batch.

Boiled for 90 minutes. Normally I do 60 minutes but in order to get enough water available for the sparge I had to boil for longer.

Oddly enough I got a lower boil-off rate of 2.8 litres/hour instead of my rate of 3.5 litres/hour despite the boil looking just as vigorous as usual. This meant the wort wasn't reduced as far as expected and I ended up with an OG of 1.088 - saved by my better than expected mash efficiency. Is lower boil-off expected for big beers? I don't know. Anyway 1.088 is fine by me and should result in a 9.0% beer.

Transferred 13 litres to the fermenter and pitched a 1.5 litre decanted starter of Wyeast 1728 at 18C. No action yet from the blow-off tube but I'm not concerned. It'll probably have kicked off by the morning.

Overall BH efficiency was 77%, only 5% down from the usual. Now if I can just figure out why I got a lower boil-off I'd be sorted for the next time.

Looking forward to trying this one at Christmas if I can keep my hands off it for that long.

 

[Ajhutch]

Nice one! I did my second RIS last weekend and came in 8% below my normal, 5% is very nice. The biggest factor (I find, don’t come at me scientists!) for boil off is ambient temperature, in this heat you’ll get less boil off than in winter. I’d be very keen to do a swap of these as and when if you’re up for it.

 

[foxbat]

I checked this morning and its bubbling away at about 2 bubbles per second so it looks like the yeast are having a bit of a feast.

I'm planning to hold it at 18 until the bubbling dies down then leave it at 21 or so for a few weeks to finish.

I’d be very keen to do a swap of these as and when if you’re up for it.

Yes OK I'd be up for a swap when these have come good.

 

[dad_of_jon]

Got up early doors this morning to get a 12 litre BIAB batch of Imperial Stout on the go. Hoping to be done and dusted before the England game at 1pm. The idea's to get this one bottled and aged for Christmas. This was my first big dark beer so I'm totally out of my comfort zone (a good thing) and had to do a fair bit of planning to get things where they needed to be.



Overall BH efficiency was 77%, only 5% down from the usual. Now if I can just figure out why I got a lower boil-off I'd be sorted for the next time.

Looking forward to trying this one at Christmas if I can keep my hands off it for that long.

I'd suggest trying one a month to see how it develops. I like imperials when younger and sweeter (3-6 months) and once they turn into liquorice bombs I age them. By then they're usually 12 months+ old. I have 6 king kong's put away and they will be 2 years old this xmas

 

[foxbat]

60 hours and fermentation has slowed from rapid fire down to a burst in the blown off tube every 4 or 5 seconds. Turned the temperature from 18 up to 20 to compensate.

 

[cheshirehomebrew]

Looks great, I might try a stout so its ready for Christmas, I wont have enough bottles spare to do the usual 25 litre batch so I might just do a couple of gallons instead

 

[foxbat]

Looks great, I might try a stout so its ready for Christmas, I wont have enough bottles spare to do the usual 25 litre batch so I might just do a couple of gallons instead

At this strength a half-batch isn't a bad thing. It also keeps the grain bill down to a reasonable size.

 

[foxbat]

I couldn't resist drawing off a sample today. It's down from 1.088 to 1.020 in 4 days flat. 9.1% and 76% attenuation so far. I knew I could trust the Scottish yeast to be up for a fight. I guess there'll be a couple more points in it before it's done cleaning up.

 

[Sadfield]

Best clean yeast ever, WY1728/WLP028.

Sent from my E5823 using Tapatalk

 

[foxbat]

Best clean yeast ever, WY1728/WLP028.

I'm not convinced those two are one and the same. My experience with WLP028 is that it's less flocculent and takes longer but does give a lovely clean malty finish. Eventually. The manufacturer's specs are quite different too.

 

[Sadfield]

I'm not convinced those two are one and the same. My experience with WLP028 is that it's less flocculent and takes longer but does give a lovely clean malty finish. Eventually. The manufacturer's specs are quite different too.

Perhaps. Can't say I've had a problem with flocculation on either and get similar results, in that neither mutes hops and give a nice residual malt sweetness. Consensus opinion is they are both mcewans strains.

Sent from my E5823 using Tapatalk

 

[cellarbrew]

Hi foxbat,

The beer looks and sounds great. I am intrigued by the equipment you used. Looks like some sort of electric boiler? Can you share details of your boiler as I am looking to go electric myself. Thanks!

 

[foxbat]

The beer looks and sounds great. I am intrigued by the equipment you used. Looks like some sort of electric boiler? Can you share details of your boiler as I am looking to go electric myself. Thanks!

The boiler is a converted 38.5l thermopot from angel homebrew. They do the conversion, you just tell them what you want in terms of valve and element and they do it. I posted some photos here. It's all you need (except the chiller) to do no-sparge BIAB. I do a dunk sparge so I also have a separate stockpot for that. I control the heat during the boil using an external box that I put together myself, documented here.

The 33l stainless fermenter is a relatively new addition. It's this one from Brewbuilder. The fittings are the same tri-clamp style used by major breweries and dairies because there are no threads or other gaps to harbour infections. With a butterfly valve and blanking plate on the bottom and a tri-clamp barb on the top lid for a blow-off tube it just fits inside my Curry's brewfridge.

 

[cellarbrew]

Awesome. Thanks a lot for all the links and info. I have been busy reading and cogitating today. Hopefully get something built and brewing up a stage from my current small 12l stockpot that I boil on the stove.

Bit unsure about BIAB. I always find the grain husks get stuck in the bag and its a right pain to clean

 

[foxbat]

Bit unsure about BIAB. I always find the grain husks get stuck in the bag and its a right pain to clean

The answer to that is easy. Don't. Rinse the large chunks out then let the bag dry. Once its dry shake out the husks. Easy when it's dry.

 

[foxbat]

There's been no activity in the blow-off tube for a few days so I decided to bottle it. FG is stable at 1.020 so basically it fermented fully out in the first 4 days and has just been cleaning up for the remaining 14 days. Great yeast that 1728.

Batch primed for 2.0 vols and got 22 bottles (11 litres). I took the precaution of re-yeasting with a pinch of dried Nottingham in each bottle just in case the 1728 is a bit knackered after all the work it's been doing. The sample jar tasted great; very smooth, roasty and warm already. ABV will be 9.1%. Now all I need to do is try to forget about it until Christmas. Not going to be easy.

 

[foxbat]

Just wondering how long you guys leave your RIS before cracking open a bottle to check carbonation is happening. Two weeks? A month?

 

[Zephyr259]

I always bottle some beer in the PET bottles I used to use so I can check how the carbonation is coming along. I'm learning that with beer at 7%+ testing them early is a bad plan as they're still a bit hot and make me worry I've just brewed a batch of fusels. Turns out that after 4 months they both became really smooth.

Would you recommend your brewbuilder FV setup? I've been tempted by their 7 gal conical but it's 2.5 time the price of the flat bottom and comes with ball valves as standard instead of the butterflies. Do you still transfer to a bottling bucket for priming? Guess you can run off the from the tap and don't have to use a siphon anymore. What kinda dead volume is below the tap?

Thanks. Oh, I saw you "Nuclear Winter" labels the other night then found this thread. Very nice.

 

[foxbat]

Would you recommend your brewbuilder FV setup? I've been tempted by their 7 gal conical but it's 2.5 time the price of the flat bottom and comes with ball valves as standard instead of the butterflies.

Yes, as long as you don't mind the extra cost of all the parts for the tri-clamp setup. Attached to the outlet I have [o-ring+clamp] -> butterfly valve -> [o-ring+clamp] -> blanking plate. And on the top outlet I have [o-ring+clamp] -> hose barb -> blow off tube. When it comes to kegging/bottling I swap over the barb and blanking plate and keg/bottle through the barb that's now on the butterfly valve. It's great that being stainless it doesn't stain (duh) and comes up as good as new after every brew. Also the lid with its rubber gasket and outer clamps is 100% airtight.

Do you still transfer to a bottling bucket for priming? Guess you can run off the from the tap and don't have to use a siphon anymore.

I've never used a bottling bucket due to the oxidation risk. When bottling I batch prime in the FV and go from the tap to the bottles. I used to do that from my old plastic FV as well.

What kinda dead volume is below the tap?

I'd guess about 2 litres but you can tilt it like you would a plastic FV.

Thanks. Oh, I saw you "Nuclear Winter" labels the other night then found this thread. Very nice.

 

[Zephyr259]

Yes, as long as you don't mind the extra cost of all the parts for the tri-clamp setup. Attached to the outlet I have [o-ring+clamp] -> butterfly valve -> [o-ring+clamp] -> blanking plate. And on the top outlet I have [o-ring+clamp] -> hose barb -> blow off tube. When it comes to kegging/bottling I swap over the barb and blanking plate and keg/bottle through the barb that's now on the butterfly valve. It's great that being stainless it doesn't stain (duh) and comes up as good as new after every brew. Also the lid with its rubber gasket and outer clamps is 100% airtight.

Thanks for the heads up on the extras, I knew you'd added the valve but didn't know about O-rings, I'd have emailed them to ask about the fittings anyway. My older standard buckets all leak and after getting a grainfather aeration paddle I found it doesn't fit inside the screw top young bucket as the opening is about 1/2" too narrow.

I've never used a bottling bucket due to the oxidation risk. When bottling I batch prime in the FV and go from the tap to the bottles. I used to do that from my old plastic FV as well.

I did this for a few batches but felt I stirred up the sediment with some yeasts which kinda undid my cold crash. Been using a bottling bucket since. That's one of the benefits of a conical, I could dump the trub early then the yeast before priming.

I'd guess about 2 litres but you can tilt it like you would a plastic FV.

Cool, thanks I lose about 1.5 L transferring from FV to bottling bucket currently so it's probably much the same.