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I think we are talking semantics here Brewfather classes the volume below the malt pipe as ‘dead space’ and is taken into account when calculating water volumes However I can see that because the volume is recoverable others might not see it that way. Hence the confusion 🫤
I suppose if you did full volume without a sparge it wouldn’t make any difference
 
Agreed, for it to make sense, is it best for me to ignore it and consider it a Grainfather "feature" 👍🏻👍🏻🤣

Dare I ask why you would not do a full volume mash in a AIO?
 
To confuse matters further Brewfather calls the unrecoverable wort left in the mash tun and kettle and pipework as a ‘Loss’ and not dead space.
As to the pros and cons of full volume versus sparge I can’t really comment other than I have tried both and get an increased efficiency with my system (2 vessel) with sparging so stick to what’s good for me. I’m sure others have found full volume works for them each to their own I suppose.
 
Absolutely, each to their own.

I too have tried both and tbh the gain want worth the faff, so use full volume. Really don't like faff in my beer, think it creates an off-taste 🤣
 
The unusable dead space between the malt pipe and the kettle wall sides is worth factoring in.
Think of it like making a cup of tea brewing it and getting it right and then topping up with some more plain water. You have dilute tea.
Hence the purpose of mixing that deadspace water.
 
The unusable dead space between the malt pipe and the kettle wall sides is worth factoring in.
Think of it like making a cup of tea brewing it and getting it right and then topping up with some more plain water. You have dilute tea.
Hence the purpose of mixing that deadspace water.
You know I have never done that and on first thinking it does make sense. However even with that space I have always found that I have hit my predicted pre boil gravity for the mashing efficiency I have used for my calculations with both my GF S40 and the Bz G4 35L . Which if you think about it is what you would expect. The space under the malt basket is factored in but so is the space around the malt basket because you have added a measured volume of brewing liquor to the kettle. I use 2.7 L per kg of grist which is plenty to this I add the volume of the space below the malt pipe also factored in to the total brew liquor required to get may preboil volume are boil off and none recoverable brewing liquors. So all of those volumes are used to predict the final gravities hence the volume around the malt basket is in fact of no consequence as it is factored into the brewing liquor requirements even though it may only become apparent when the mash is over and the malt basket raised to sparge the grains. It is possible that efficiency could be increased by using the brew liquor around the malt basket for recirculation during mashing though but it would require an experiment. One could simply raise and lower the basket during the mashing to mix in that liquor? So I am sorry but to me the cup of tea analogy does not work as you already know that the dilution is going to occur before you start brewing.
 
This so called "dead space" is only recirculating wort that is pumped through the mash as it runs through it to the bottom to be recirculated again over and over.
I do not understand the terminology of the word "dead space" it is part of the wort.
The only thing it really applies to is part of it becomes kettle loss as trub gathers at the bottom of it
 
This so called "dead space" is only recirculating wort that is pumped through the mash as it runs through it to the bottom to be recirculated again over and over.
I do not understand the terminology of the word "dead space" it is part of the wort.
The only thing it really applies to is part of it becomes kettle loss as trub gathers at the bottom of it

I suppose you can call it what you like but it does have to be taken into account as you know. If you do not takes the space under the malt basket into account then most AIO systems would not work well at all. Taking my S40 as an example, it has 7L of space below the level of the bottom of the malt basket. For a 5 kg bill you would only need 13.5L for mashing try using that volume to mash and recirculate in an S40... I don't think so grain absorption and the volume below the malt basket accounts for 11 L then you have the space around the malt basket and the kettle wall to take into account, that is going to be one stiff mash.
I do not think anybody using the term dead space is suggesting that the volume is not part of the wort, rather that it is a volume that has to be added to the volume of liquor that has been calculated for mashing volume, grain absorption, trub loss, sparge volume and boil loss when calculating the total volume of brewing liquor required to achieve an in the fermenter post boil volume which gives the calculated wort gravity . If you use any of the brewing calculators the volume is nearly always referred to as "dead space" and is a constant for the system you are using together with grain absorption, boil loss and trub volumes.
I do find the debate about this subject a bit pedantic to be honest. Every man and his mutt knows that the volume described is part of the wort but if it is a concern maybe call it "liquor below the grain basket" ... that would work. athumb..
 
To be honest Jambop I use virtually a set amount for mashing whatever AIO I am using which is probably well above the amount some brewers use so it does not really matter to my brewing method.
I use the same amount of water in the mash/"deadspace" as the amount of beer I require, so a 20ltr brew will get 20ltr of mash water and so on, I then do a simple batch sparge to my pre boil volume accounting for my boil off etc.
I like a loose mash and would do a full volume if it wasn't for needing to do a quick rinse to get some of the extra sugar into the wort just for a reasonable BH eff.
 
This so called "dead space" is only recirculating wort that is pumped through the mash as it runs through it to the bottom to be recirculated again over and over.
I do not understand the terminology of the word "dead space" it is part of the wort.
The only thing it really applies to is part of it becomes kettle loss as trub gathers at the bottom of it
Thank you. I thought it was just me.
 
Thank you. I thought it was just me.
It's alright Brian no doubt the brewers that believe all the critical hype of you must do this at 64.25c and need 0.875g of Calcium Phaffaldehyde enzyme or it will ruin your brew proves we have been doing it wrong for the last 40 years :laugh8: :laugh8: :laugh8: .
Ps this is a tongue in cheek comment:laugh8::laugh8::laugh8:
 
As long as your calculations / outcome takes account of the volumes, whether you know or understand them is irrelevant.
The tea analogy does work because you'd do something about your tea making process if your tea was too weak or strong.
This is what you have done because you say your numbers are right.
A more liquid mash or more sparge can end up with the same volume and gravity of wort.
 
As long as your calculations / outcome takes account of the volumes, whether you know or understand them is irrelevant.
The tea analogy does work because you'd do something about your tea making process if your tea was too weak or strong.
This is what you have done because you say your numbers are right.
A more liquid mash or more sparge can end up with the same volume and gravity of wort.

The fundamental in all these predictive calculations is in fact mashing efficiency. Mashing efficiency can only be assesed by experiment and then by average. If you use the same AIO for your brews and have established a good average mashing efficiency figure for various grain bills then the volume around the basket is irrelevant because your experiments have proved that when the basket it removed and the grains sparged you get an expected efficiency it does not matter that the volume has not been allowed for you have done the experiments that take care of dilution effect that volume.
I have done three brews so far with my Bz and come up with 83,85 and 86 % mashing Eff the latter two are high in my opinion because one was mashed at 65C and the other contained a high crystal malt mixture at 16% of the grist which boosted the gravity. I would say I have to base my calculation on about 82% mashing. As to the fixed volumes used in the predictive calculations vol below the basket , grain absorption, boil off rate, trub loss and mash liquor to grain mass are constants.
Just my take but I cannot see how predictive brew calculators can work unless you know what your mashing eff is .
 
Just my take but I cannot see how predictive brew calculators can work unless you know what your mashing eff is .

I don't know my efficiency or use predictive calculators.
I am reasonably sure my life is richer without either. Perhaps its experience, but it is each to the own.

My hands can tell water temperature with 2 or 3 degrees. So it is probably experience.
 
I don't know my efficiency or use predictive calculators.
I am reasonably sure my life is richer without either. Perhaps its experience, but it is each to the own.

My hands can tell water temperature with 2 or 3 degrees. So it is probably experience.
So what you are saying is you follow recipes OR you just don't care what the gravity of your beer comes out at ?
I will take you all the way that you can tell the difference between 64C and 67C or 68C and 71C at that temperature you are scalding yourself. Perhaps its BS ?
 
So what you are saying is you follow recipes OR you just don't care what the gravity of your beer comes out at ?
I work my recipes out myself. The gravity is within my margins. Do I need to know it to two decimal places. Nope.

I will take you all the way that you can tell the difference between 64C and 67C or 68C and 71C at that temperature you are scalding yourself. Perhaps its BS ?
It was a serious point and for the reason you mention I don't use it for mash temps 🤣🤣
 
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