Imperial Stout - double mash?

[ElectricLandlord]

Hi guys,

I'm planning a RIS and aiming for about 1.100 as an OG. I think I can just about get all the grain into my cooler mashtun but I tend to get big problems with such large grain bills due to the weight crushing my braided hose. I was thinking of basically mashing twice - i.e. mash with half the grain, sparge as normal, drain to the kettle then empty the mashtun and repeat with the other half of the grain. Then boil as normal etc.

Does anyone recommend this approach? And if so, how do I put it into BeerSmith in order to calculate the water volumes etc?

Many thanks,

Martin

[spiderwrangler]

The grain should help hold itself up off the braid to some degree, but if you've had problems with it before, you know your system better. If you wish to try this, I set my batch size to half batch for mine if I'm doing all grain in the kitchen. I'll do a half batch, boil and hop as normal, cool, transfer to carboy while the second batch is mashing. Takes a bit more time, but prep and cleanup is the same either way, so not too bad. Besides, then I get to make beer twice as much! You'd be able to skip the full boil part and just be running off twice, but would probably want to bring your initial runnings up to a high enough temp that you don't have continued enzyme activity while the second is mashing.

[agstockstill]

Should work, I would calculate 1.100 for half of what you want in the kettle. If you’re shooting for 8 gallons (30 liters) to begin your boil, figure out what 1.100 would be for 4 gallons (15 liters). Also have you considered just throwing a little DME in?

Cheers,
A.G.

[Ozwald]

I don't see any serious issues with that, I've done similar mashes myself. I find that my grist ratio starts getting a little too thick for comfort on anything over 1.080. More frequently though, I elect to scale down the batch, do a longer boil, or do a double brew day. I'm a ProMash user & likely always will be, so I can't help you with details on BeerSmith's workings. I would suggest you assume your mashtun is twice it's actual volume when doing the calculations & proceed as normal. I don't use the water calculator, I just watch my total mash volume & grist ratio. If you need to do any serious treatments to your water, such as adjusting brewing salts (something I don't watch on huge beers since I don't do them very frequently) you may need a bit more consideration, but on a small scale you can usually get close enough by considering that 100ppm in 10 gallons is 50ppm in 20 - perhaps not precisely, but it'll very likely get you close enough without a few years of chemistry classes. Just start cutting things in half to share between the two mashes - grain, water, additions, etc. - and I'd bet you'll get a very drinkable beer out of it and also give yourself a baseline to tweak for the next batch. I've brewed great beers the first try, but never a 'perfect' one. There's always something I'd like to tweak a little bit more, I just enjoy the 'research' getting there. As for the boil, I'd just keep the first batch covered up, let it keep the heat from mash & let it cool naturally. Even if you're above the point where some of the volatiles are making their way back in, you'll still knock them back out during the main uncovered boil. I suggest covering to keep out bugs (of the insect variety, not the bugs we typically talk about) and all the 'snow' from the cursed cottonwoods around here. They might look nice, but they never seem to drop anything until I start sparging.

Hope this was the kind of advice you were looking for. My version of 'Relax, don't worry, have a homebrew!' I suppose. Enjoy the brew & let us know how it goes.

Cheers!

[ElectricLandlord]

Excellent, thanks for the assistance guys. Good thought about continuing enzymatic activity, Spider. I know I'm setting myself up for a long brewday, but the output should be worth it, right?

I think I'll create 2 versions of the recipe in BeerSmith - one at half volume (for the mash stage) and one at full volume (for the boil stage onwards). Will let you know how it goes.

Cheers,

Martin

[Ozwald]

Definitely worth a double brew day. I even pushed a triple once, running solo. Just got my 15 gallon conical & hadn't finished the bigger system yet. Won't ever do that again. The double's are a walk in the park now.

A tip, do everything you can the night before. Make sure your HLT is full, everything measured for both batches, grain milled, etc. It'll save you a lot of hassle & time. I've even timed it out so that the second my kettle is drained from the first batch, I'm running off the 2nd mash right into it. You can pull off two 5-hour brews in 7 hours or so, depending on how your system is set up.

[spiderwrangler]

A tip, do everything you can the night before.

+1

[Ozwald]

A tip, do everything you can the night before.

+1

I'm an early riser anyways, but I even prep my coffee maker. There's nothing quite like waking up to hot coffee & just stepping outside to fire the burners without dealing with anything else. I can get my HERMS coil & HLT close to temp before I'm done wiping the sleep out of my eyes. I can start brewing by 5 & be cleaned up in the early afternoon. I hate it when that 2nd batch is still working when it's starting to get late & I'm tired.

I even like to weigh out all my hop additions into small Gladware containers. I nest them with late additions on bottom & bittering additions on top, the 2nd batch under the 1st. It only requires one lid & I use blue painters tape to keep them together when I throw them back in the freezer overnight. I do it in one stack so I can just dump the top container in when a timer goes off without thinking about it or reading any labels. The milled grain buckets all have lids on, but they're stacked essentially the same way.