FAO Grainfather Users, Re. Underletting?

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strange-steve

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I always used the underletting method for doughing-in on my old 3V system, I found it meant much less stirring of the mash was required, and no dough balls. I was wondering has anyone tried this on the GF? I was going to try something similar with my next brew by 1. Resting the grain basket in the sparge position. 2. Pouring the grain into the basket. 3.Slowly lowering the basket into the water.

Any thoughts?
 
That is basically what the Braumeister does as it pumps the water from the bottom up and through the mash.

I think you’ll get a bette result going the way your describing.

I’ve found I’ve never had any dough balls. And it may explain the extraordinary efficiency I seem to get. Even more now I’ve changed the mesh filters to laser cut ones. It was even higher than usual.......


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I have started adding +1L to the GF calculated mash water volumes, and subtracting 1L from the sparge volume. Makes mashing in quite a lot easier, and means 1 less jug of sparge water. Not sure what the drawbacks of doing this might be. Lower efficiency? But it seems to work ok.
 
I have started adding +1L to the GF calculated mash water volumes, and subtracting 1L from the sparge volume. Makes mashing in quite a lot easier, and means 1 less jug of sparge water. Not sure what the drawbacks of doing this might be. Lower efficiency? But it seems to work ok.



That’s also interesting. for a while now I’ve worked out that I get a better mash in and efficiency by basically maxing the mash in water volume to best part of 23+ litres.


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That’s also interesting. for a while now I’ve worked out that I get a better mash in and efficiency by basically maxing the mash in water volume to best part of 23+ litres.


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That's the opposite of what I'd expect, I would have thought the efficiency would drop as you reduce the sparge volume :hmm:

I'm actually planning a no-sparge Marzen soon which will be a full volume mash (or at least as close as I can get) but I have factored into the recipe a fairly substantial efficiency drop. Suppose I'll wait and see how it goes.
 
One other benefits in underletting will be reduced flour sitting on the element, so less chance of scorching especially when step mashing a wheat or rye beer.
Like I did.
 
I make up my mash water plus a little extra, then add as much as is required as I mash in, it's usually a bit less than I have prepared.
 
That is basically what the Braumeister does as it pumps the water from the bottom up and through the mash.

I think you’ll get a bette result going the way your describing.

I’ve found I’ve never had any dough balls. And it may explain the extraordinary efficiency I seem to get. Even more now I’ve changed the mesh filters to laser cut ones. It was even higher than usual.......


Sent from my iPad using Tapatalk

Id be interested to know more about those laser cut mesh filters. Where did you get them?
 
Id be interested to know more about those laser cut mesh filters. Where did you get them?



Brewuk have them. They seem to have a few extra “add on’s” made by Spiedel and other manufacturers for the BM. I’ve been really pleased with them. They won’t fall apart like the standard ones do.

I’m just about to order the wort pump extraction add on from Brewuk so I can pump out of my BM straight into my new fermentasaurus.


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Brewuk have them. They seem to have a few extra “add on’s” made by Spiedel and other manufacturers for the BM. I’ve been really pleased with them. They won’t fall apart like the standard ones do.

I’m just about to order the wort pump extraction add on from Brewuk so I can pump out of my BM straight into my new fermentasaurus.


Sent from my iPad using Tapatalk

Found them. The BM mesh is a pain to clean especially when the edge frays and stabs you in the finger! Ill definitely consider them. :thumb:
 
That’s also interesting. for a while now I’ve worked out that I get a better mash in and efficiency by basically maxing the mash in water volume to best part of 23+ litres.


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I start with 23L the majority of the time too. Last brew I measured the end of the sparge run off and it was 1.020 so my thoughts were that I could of extracted more from a bigger sparge?? I hit my target SG, but was using freshly crushed grains.
 
So it appears nobody has tried this yet, maybe there's a good reason for that though :? I'll report back in a couple of weeks when I've tried it!
 
I have started adding +1L to the GF calculated mash water volumes, and subtracting 1L from the sparge volume. Makes mashing in quite a lot easier, and means 1 less jug of sparge water. Not sure what the drawbacks of doing this might be. Lower efficiency? But it seems to work ok.

I just use a simple formula: Grain Bill in Kg times 3.5, so 6kg gets 21L.

As far as efficiency goes, I find the longer I spend doughing in (say 25 mins) and the more often I stir a mash that is not running freely through the grain, the better efficiency I get.

Also a very slow sparge helps, tedious though it is, and I aim for 25L in the FV every time.

Now up to 75% or so, for pre-crushed grain, at around 5.5kg grain bill. Efficiency suffers with bigger grain bills, mainly because it seems such a tedious business doing all the extra stirring, but maybe as this takes away too much sparge water.
 
Last beer I did with my GF, I put the grain in a bucket a gave it a shake to get the larger grains and husks towards the top. I loaded them into the mash tube first, then with later more floury grains including some wheat, I loaded them in with some rice hulls. Just gave one stir half way through mash, which I could have done without looking at my numbers.
I was aiming for 75% efficiency but ended up with 80%.
 
Okay an update on this...

I'm brewing a kolsch today and tried using this underletting method. So I set the grain basket in the sparge position like so...
3hv1bj4.jpg


Then I chucked a handful of oat husks into the bottom of the basket and poured the the grain on top thusly...
1DdmzNW.jpg


Out of curiosity I lifted the basket to see how much "stuff" had fallen through the mesh, not much at all as it happens...
cMgp5vV.jpg


Then I slowly lowered the basket into the preheated strike water. The grain has a tendency to float if lowered too quickly so just slow it down a little and let the water seep up through the grain. This is how it looked before stirring...
lP9Y8d3.jpg


It took very little effort to get it well mixed in, and significantly less time than usual. This is it after a brief (30 sec) stir with the paddle...
9yu2tx8.jpg


Mash pH after 15 mins...
Awb6wL8.jpg


Now this part's interesting (warning, only proceed if you're a gobs*ite science type!) We often hear that starch conversion is complete after only 15 or 20 mins, so I checked the conversion efficiency at 2 different points during the mash.

The estimated maximum extract content according to Braukaiser's formula includes the variable of average laboratory extract which is only available from the malt analysis, but using 80% is usually pretty close.

As it turns out that was a little low, so using the actual* 100% conversion efficiency, these are the results:

After 15 mins at 55° and 30 mins at 63° the conversion efficiency was 81%. That's quite significant, because according to Braukaiser if your CE is lower than 90% then you need to have a serious look at your mash parameters.

I then stepped up from 63° to 70° for 30 mins, and after this rest the CE was at 100% :thumb:

So I found it interesting that after about 50 mins (including ramp up time) the CE was pretty far from complete. Now that could be down to many factors, the dough-in method, not stirring enough, the low mash temperature etc. but this example shows that conversion isn't necessarily complete after 20 mins. That's not to say it can't be though; under certain circumstances it may well be, but I don't plan reducing my mash times any time soon.

As of now (just coming to the boil) the preboil SG is indicating that I'm a few points higher than expected and currently on par for 81% BHE which is the highest I've got with the GF. So I suppose the conclusion for me is that underletting is quicker, easier and has no negative impact on BHE.

*An assumption based on the fact that my CE was >100% according to BK's formula.

Edit to add: I've just checked the actual BHE and it's 80%, result :thumb:
 
Hi!
Great post, Steve (or can I call you Strange? :grin:)
I don't have a GF but have tried underletting - I do it on every brew now.
Underletting is supposed to reduce the risk of doughballs and therefore you probably don't need to stir it as much as usual. I wonder whether you need to stir it at all? Could the recirculating wort be seen as similar to stirring?
I tried conditioning the grain first and using a slightly tighter crush - I was trying to get a better grain bed without reducing efficiency. It seemed to work. I also use flaked barley as a base before adding the grain.
Your next project could be to devise some mechanical means of controlling the lowering of the malt pipe into the GF.
I drooled over your pH meter - I want one!
Again, a great post - breakthrough, perhaps?
 
A bit too much in the kettle for my liking, packing the grain pipe could perhaps be done off the kettle over a big bowl or plate tho ;)

While i too underlet with my 3v too, the smaller grainbill in the G/F is easily manageable to mash in without any doughballs but i may give this a try myself next brew..
 

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