Grandfather for a big beer?? Experienced Users...

[aamcle]

I'm going to brew Jamils Christmas Beer but it takes 9kg of grain right on the GF's maximum.

According to the GF calculator I'd need 27 l of water for the mash and 13 to sparge which isn't enough to adequately sparge that amount of grain so efficiency will be lower. This was my experience the last time I did a big beer in the GF.

Would the following offer any significant advantage?

Mash as normal then pump the wort into a bucket.
Add 1/2 the sparge water to the GF and recirculate it through the grain then pump it into the bucket.
Do the same with the other 1/2 of the sparge water then lift the grain and return all the wort to the GF.

The other and obvious way forward would be to use more sparge water and boil for longer.

What would you recommend?

Thanks All.

Aamcle

 

[hopjuice_71]

Look into reiterated mash. I haven't done it, so I don't know the precise volume calculations, but conceptually it involves mashing ~1/2 the grains and sparging, then bringing that wort to strike temperature again, mashing the other half of the grains, and sparging again. No running off to a separate bucket - it all occurs in the GF.

 

[cmybeer]

A couple things: you could lower your total volume and do a four gallon batch but that wouldn't be very fun so option two; take out some basemalt and add dme preboil.

 

[couchsending]

It’s such a PITA to brew big beers on the GF. Your efficiency goes way down as well as not being able to fit enough grains in. You can do 3 gallon batches of High Gravity but a full 5-6 gallons is virtually impossible. Recently I did 3 gallons with a starting gravity of 1.115 but even then it was with some DME and Lactose and an efficiency of 65%. I boiled for 2.5 hours as well. I guess you could double batch into one fermenter. Never done a reiterated mash, maybe one of these days.

 

[deadwolfbones]

Look into reiterated mash. I haven't done it, so I don't know the precise volume calculations, but conceptually it involves mashing ~1/2 the grains and sparging, then bringing that wort to strike temperature again, mashing the other half of the grains, and sparging again. No running off to a separate bucket - it all occurs in the GF.

I did this with a 13% stout (in my Robobrew) and it works great. Just takes a long-ass time. I think my brew day was about 10 hours. There's a post about it here: https://brew4fun.wordpress.com/2019/01/13/polygyle-party/

The other option is to make two batches back to back with a split grainbill. I did this recently with two 4 gallon batches of an 11% barleywine, dividing it over two days.

I should probably mention that I took the grain pipe out of my Robobrew and do BIAB with a custom bag, which increases the space you have to work with a little.