Brewfather and capacity calculations

[hoppyscotty]

My mash vessel has a max working capacity of 70 litres. I'm working on a big Impy stout recipe which I did on my 35ltr Brewzilla last year via a reiterated mash yielding about 15 litres I think to keep within the capacity constraints of the system. I'm looking to do a larger batch on my bigger system this year.

I started looking at a 40 litre batch size for starters but looking to max the system out as the batch will be aged over different periods of time, and it came out with something like 50litres of strike water and an 18kg grain bill. I know there is grain absorption to consider but that sounds like it might be pushing I terms of volume of the strike water plus volume of the grain. Does Brewfather take the capacity limitations into account? I cant see a mash tun cpacity field in the equipment profile, only a kettle pre-boil volume field.

How would I calculate the total volume of grain plus strike water taking into account grain absorbtion?

When normally mashing in the total volume doesn't seem to be much greater than the volume taken up by the grain so I guess I go with volume of grain plus a little bit?

Thanks

 

[AJA]

I calculate that to be around 63l, plus your dead space.
Will fit but not much sparge room.

 

[hoppyscotty]

OK thanks. Not much dead space beneath the false bottom as it's quite close to the vessel floor so should get away with it. I sparge really slowly anyway so as long as there is room for an inch or so of water on top of the grain I'll be OK.

How did you calculate that?

Thanks

 

[AJA]

The rule of thumb I found was strike + grain on kg *0.652

I checked this against some calculators I found on Google and it seems to tally up.

I'm not sure what grain absorption ratio is built into that, but worst case scenario you can increase the multiplier by 20%, then you have 65l which is still ok.

 

[RoomWithABrew]

My mash vessel has a max working capacity of 70 litres. I'm working on a big Impy stout recipe which I did on my 35ltr Brewzilla last year via a reiterated mash yielding about 15 litres I think to keep within the capacity constraints of the system. I'm looking to do a larger batch on my bigger system this year.

I started looking at a 40 litre batch size for starters but looking to max the system out as the batch will be aged over different periods of time, and it came out with something like 50litres of strike water and an 18kg grain bill. I know there is grain absorption to consider but that sounds like it might be pushing I terms of volume of the strike water plus volume of the grain. Does Brewfather take the capacity limitations into account? I cant see a mash tun cpacity field in the equipment profile, only a kettle pre-boil volume field.

How would I calculate the total volume of grain plus strike water taking into account grain absorbtion?

When normally mashing in the total volume doesn't seem to be much greater than the volume taken up by the grain so I guess I go with volume of grain plus a little bit?

Thanks

I use a guten 70 litre so similar size. The imperial I did last year for a 23 litre batch was 15.5 kg of grain and it calculated 32.7 litres of mash water. Only 6.3 of sparge.

So I actually went stiffer on the mash to increase the sparge water.

Brewfather for me shows in the water section after total water the Mash Volume ( ie water and grain).

In this case it reckoned 42.8 litres total at the mash stage. Might be a setting you need to turn on?

I didn't get great efficiency due to the rye blocking up all of the holes in the malt pipe so had a stuck mash and sparge nightmare. Only managed 55%.

But did manage a 23 litre partigyle batch on the second runnings at 1.037 which I added some invert to.

 

[hoppyscotty]

Ah so the total mash volume is what I need to look at? I know where that is but never really paid much attention to it before as I've always operated within the system limits. Thanks.

 

[hoppyscotty]

I calculate that to be around 63l, plus your dead space.
Will fit but not much sparge room.

Looking at the total mash volume you were very close indeed!! came out at 61.45 litres!

 

[RoomWithABrew]

Having listened to a few podcasts on imperial stouts from Craft Beer and Brewer, the Alaskan brewery head brewer feeling was you crammed as much malt into your mash tun as possible ( with the water) and that was your base.
I find it quite stressful with a maxed out malt pipe to the brim. A lot of stirring as well which is hard labour and then I do the second runnings beer as well. I think a barley wine and an Imperial stout a year is my limit, but next time should be better based on my previous learnings. But that's not till August so a few months of respite.

 

[AJA]

We did a partigyle here, but we split the mash between my cooler mash tun and a grainfather. The cooler went without a hitch, but the grainfather got stuck and burnt. In hindsight should've gone for the giant mash in the cooler! It's a lot easier to mash in with grain and strike water separate.

The second runnings were way lower gravity than we expected, luckily I had a MG LME pouch close to it's BBE that I boosted it with.

Overall efficiency is very low, problem won't try again!

 

[RoomWithABrew]

It's that problem of more grain more absorption of liquid. 1 kg of grain absorbing 600 ml of liquid and then you need to get the sugars out. Next time if I got my BHE to 60 percent I'd be really pleased, then I'd do the partigyle on the runnings but keep an eye on the gravity of the runoff to dictate my volume.
Without the second batch you will be throwing away half of your sugars still wrapped up in the grain which feels wrong to me.

 

[hoppyscotty]

this is what n my 3 vessel system so have a max kettle capacity of 100litres so can do a proper sparge. The issue I had last time I did this in my BZ as a reiterated mash was a really sticky second mash that really hurt my extraction in that second mash. I know what my mistake was but hopefully with a single mash and big sparge I can get better efficiency this time around.

 

[private4587]

this is what n my 3 vessel system so have a max kettle capacity of 100litres so can do a proper sparge. The issue I had last time I did this in my BZ as a reiterated mash was a really sticky second mash that really hurt my extraction in that second mash. I know what my mistake was but hopefully with a single mash and big sparge I can get better efficiency this time around.

Hi I am very interested in trying an Imperial Stout in my 35lt Brewzilla but I am unable to find any info in Brewfather about reiterated mashes, could you please let me know your method i.e. calculating water volumes used. Thanks

 

[hoppyscotty]

Well I kind of winged it as I also couldn't find anything to help me calculate things but plenty of info around on how to actually do it. I just worked out the full batch data in Brewfather, which threw up warnings about capacity limitations and just halved everything. Probably my methods is all kinds of wrong but actually the mash worked out quite successfully apart from the fact the second mash was super thick and I got a stuck mash and the problem there was I took both allocations of the sparge volume and did one sparge after the two mashes. The second mash needs that additional water from the first half of the total sparge water.

So all in all fell short of OG - was aiming for a 12% ended up with a 9%, second mash was sticky due to no performing an intermediate sparge (or you could just add half your sparge volume to your first mash volume).

The brewzilla makes it easy...after the first mash raise the basket and let it drain (and do sparge at this stage) them empty basked, I gave it a hose down to clear grain stuck on the fine mesh and perforated bottom, re-loaded the basket into the vessel and mashed in again.

 

[hoppyscotty]

If I were doing it again in the BZ I'd assume a lower efficiency and be more generous with either strike water for the first mash or make sure I do a decent sparge after the first mash.

 

[private4587]

If I were doing it again in the BZ I'd assume a lower efficiency and be more generous with either strike water for the first mash or make sure I do a decent sparge after the first mash.

Many thanks will give a go and hope it’s ready for next Christmas