Large Grainbill

[Mark Weusten]

I heard Imker say on one of the demo vids that the GF could hold up to 9kg. On saturday my grainbill was 7.6kg and I calculated my mash volume using the supplied calculation in the handbook. I dont know how much more it would handle. The recirculated water was going down the handle holes and taking debris with it. The instruction video says to place the top perforated plate above the grain line and not to compress. Anyone done larger than 7.6kg so far?

[Mark Weusten]

Mine seem to be low, on my 7kg Pale Ale I got 1.068 but mashed at 65c so expecting it to finish low around 1.012 giving just over 7% abv. I saw someone got 1.066 off the Chur kit.......

[Peter Smith]

thinking off the cuff, how about doing a 60 min recirc with 5kg then pouring the wort out and doing another 60 min recirc with another 5g kg, then rejoin for boil sure need a urn to preheat the 2nd mash water, what is the pre sparge gravity you are seeing? as if say 1.070 and you do this twice then boil 120 mins you going to get a big og

[Mark Weusten]

That was my initial thought when doing the iStout. I think it gets better efficiency with lower grain bills.

[Mark Weusten]

I had intended to use 1272 in this beer but decided to wash it properly instead of dumping it on the old cake. So ended up using 2nd gen US05 and Mr Maltys told me 430 ml so I pitched 600ml to be sure. It sounded like a machine gun the next day. It seems to have finished but the hydrometer will tell me I guess.

[David R]

Bumping this up again, I'm planning a Barley Wine for my next brew and would like to hear how far people have pushed the GF with large quantities of  grain. This is where I'm at with the recipe, basing it off this one here ( http://www.homebrewtalk.com/showthread.php?t=232233 ) it looks like I should be able to hit just over 10% ABV with 8.72kg of grain plus 680g of brown sugar. However, I'm aware that the efficiency is likely to be reduced with a larger grainbill, but by how much?

Also, is 8.7kg going to be comfortable? From Marks experience it sounds like 9kg is too much, what are people finding is the upper limit?

Anyway, here's the recipe as it stands, open to suggestions!

Batch Size: 23.00 l
Boil Size: 28.00 l
Boil Time: 60 min
Efficiency: 73.00 %
Est Mash Efficiency: 82.1 %
Est Original Gravity: 1.092 SG
Est Final Gravity: 1.015 SG
Estimated Alcohol by Vol: 10.3 %
Bitterness: 90.1 IBUs
Est Color: 15.0 SRM

Ingredients

Amt	Name	Type	#	%/IBU
4.10 kg	Pale Malt (2 Row) UK (3.0 SRM)	Grain	1	43.6 %
2.70 kg	Munich Malt (9.0 SRM)	Grain	2	28.7 %
1.36 kg	Rye Malt (4.7 SRM)	Grain	3	14.5 %
0.45 kg	Caramel/Crystal Malt - 60L (60.0 SRM)	Grain	4	4.8 %
0.11 kg	Caramel/Crystal Malt -120L (120.0 SRM)	Grain	5	1.2 %
55.00 g	Chinook [13.00 %] - First Wort 60.0 min	Hop	6	57.5 IBUs
0.68 kg	Brown Sugar, Light (8.0 SRM)	Sugar	7	7.2 %
80.00 g	Northern Brewer [8.50 %] - Boil 20.0 min	Hop	8	30.1 IBUs
40.00 g	Northern Brewer [8.50 %] - Steep/Whirlpool 5.0 min	Hop	9	2.5 IBUs
2.0 pkg	Nottingham (Danstar #-) [23.66 ml]	Yeast	10	-

[Mark Weusten]

Hey David, in hindsight I think my water volumes was my biggest problem.The water volumes calculator on the website doesn't work well. It tells me you should be using 27 litres of mash water, if I had known my GF well at this stage I would have thought "where is this 9kg of grain going to fit?" I would reduce that considerably and then add from an urn as required. I got an overflow when I did this. I think the recipe looks good and I think you will achieve your desired abv. I was getting 9% off 8 kg and 500 g of dextrose in an imperial IPA.

[David R]

Cheers Mark, I was wondering about the volumes, according to the calculations I should me mashing that recipe with 27.1L, can't see that working well! I guess there will be a lot more absorption with the larger amount of grain, I'll have the urn on stand-by to top up as required.

[Steve Dorrington]

Hi David

Did you brew this barley wine at all?  If so how did it come out? 

cheers