Should a thin, or a thick mash, give higher mash efficiency?

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Brews prior to BT probe, always came out fine, correct OG, but often ended at SG below target. But I've had a couple recently (OG still correct) but maybe too high in dextrins (taste & final gravity ending on high side). So I'm beginning to wonder if mashing at accurate 'correct' temperatures is actually too hot.
That is mash temperature, nothing to do with water/grain ratio.
 
🤣 Whoever told you that is pulling your chain. BIAB will, but the AIO's are limited by crush
Told me?

Those were figures predicted by beersmith and then achieved in the real world in two brews I did. AIO are BIAB, with recirculation.

AIO is not in any way shape or form sparging, more of a vorlauf. Depositing debris from the mash onto the top of the grain bed.
The action of moving liquid through the grist rather having it static is going to have the same effect. It clearly works as people report good efficiency on full volume mashes in AIO, RIMS and Herms systems. No doubt they will turn out wrong or are lying.
 
Told me?

Those were figures predicted by beersmith and then achieved in the real world in two brews I did. AIO are BIAB, with recirculation.


The action of moving liquid through the grist rather having it static is going to have the same effect. It clearly works as people report good efficiency on full volume mashes in AIO, RIMS and Herms systems. No doubt they will turn out wrong or are lying.
Yes told you. There is no way a no-sparge will achieve 80%. Otherwise, why would anyone bother sparging?
The grist is suspended in the wort no matter what method is applied the sparge whether batch or fly washes out the sugar trapped in the grain bed. No sparge leaves around 20% of the sugar trapped in the grain bed. You can whinge and whine till the cows come home but you won't convince me or any other no sparge brewer you get 80%. In other threads you always claim to be a stove topper, not a AIO brewer.
 
I'd stick with what you are doing. At 2.7l per Kg, you can't really go any thicker (lowering mash in and increasing sparge volume) without hitting extract issues as shown in the graph earlier. 2.7 is what Grainfather suggest as the most efficient for their systems.

What mash and brewhouse efficiency figures are you getting?

As general observation, needing some form of sparge water vessel does appear as a failure of principal, of systems that claim to be All In One.

Yes I do use the GF suggested 2.7L per kilo with my S40 but when you take into account the volume below the malt basket the overall ratio is about 3.5L per kilo. I regularly hit mashing effs of 85 % but my brewhouse is always between 5 and 10% less than my mashing as the S40 always has a fair bit left in the bottom after transfer. You are right re sparging I use a stainless kettle for sparging through an external pump but now I have the Brewzilla and the S40 I can use either of those to sparge. Brewzilla say that 75% is a realistic brewhouse eff for the 35L system I would hope to better because there should be next to nothing left after transfer that but that remains to be seen.
 
In other threads you always claim to be a stove topper, not a AIO brewer.
I can do either. I prefer the involvement, hands on, lack of automation of 3 vessel. Much in the same way as I won't use a bread maker, I'll do it manually. Evidently, it's a rare thing, but I actually enjoy the process of brewing, it's quite relaxing. Others sit cross legged by a babbling brook to reach zen, a trickle of sparge water does it for me.

This appears a serial issue for you.
https://www.thehomebrewforum.co.uk/threads/full-volume-mash.92209/
 
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Yes I do use the GF suggested 2.7L per kilo with my S40 but when you take into account the volume below the malt basket the overall ratio is about 3.5L per kilo. I regularly hit mashing effs of 85 % but my brewhouse is always between 5 and 10% less than my mashing as the S40 always has a fair bit left in the bottom after transfer. You are right re sparging I use a stainless kettle for sparging through an external pump but now I have the Brewzilla and the S40 I can use either of those to sparge. Brewzilla say that 75% is a realistic brewhouse eff for the 35L system I would hope to better because there should be next to nothing left after transfer that but that remains to be seen.
85% mash efficency, and 75% into the FV efficiency, are good numbers.
 
Yes told you. There is no way a no-sparge will achieve 80%. Otherwise, why would anyone bother sparging?
The grist is suspended in the wort no matter what method is applied the sparge whether batch or fly washes out the sugar trapped in the grain bed. No sparge leaves around 20% of the sugar trapped in the grain bed. You can whinge and whine till the cows come home but you won't convince me or any other no sparge brewer you get 80%. In other threads you always claim to be a stove topper, not a AIO brewer.

So I am not taking sides in debates but I do keep quite comprehensive details of my brews.
Here are some figures from a recent TT's clone recipe I devised.
Total grain bill 4.83 kg
mash liquor 20.15 L
mash gravity at T90' 1.058 assuming grain absorption @ 0.8 L per kg mash volume = 16.286 so total gravity points = 944.6 but the total liquor volume would yield 1160 pts

sparge liquor 16.25L
volume after sparging = 33.25L @ 1.038 total gravity points = 1263.5 mashing effiency was 84%

sparging delivered 103 gravity points which equates to about 8% of the total gravity points obtained during mashing.

However one has to realise this was not a full volume mash so I cannot say what would have happened had I done that. The firgure for the sparging points could have been lower because of the increased reciculating volume.

edit
Looking at the figures I am inclined to think that a full volume mash would deliver much closer to the total gravity points obtained that these calculations would suggest. For example if we take the total points obtained from the 20L mashing volume and compare that to the points obtained from notional volume less grain absorption we see that the sugars held in the grains prior to sparging is only 103 pts ... is it not reasonable to assume if we increase the mash volume to the full 36L liquor volume that these gravity points would have been eluted from the grains by wort recirculation during the 90' mashing period ? I personally am inclined to think that this is very likely.
 
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I put 32 litres of water in a burco boiler and add 11 lb of crushed pale malt to my BIAB. Mash for 1 hour, drain off liquid into boiler, boil for around 30 minutes, yielding 22 litres of wort. I have never calculated efficiency. Finished beer is close to 3.8% - I am happy with the finished beer, which I find is best drunk within 4 weeks.
 
So I am not taking sides in debates but I do keep quite comprehensive details of my brews.
Here are some figures from a recent TT's clone recipe I devised.
Total grain bill 4.83 kg
mash liquor 20.15 L
mash gravity at T90' 1.058 assuming grain absorption @ 0.8 L per kg mash volume = 16.286 so total gravity points = 944.6 but the total liquor volume would yield 1160 pts

sparge liquor 16.25L
volume after sparging = 33.25L @ 1.038 total gravity points = 1263.5 mashing effiency was 84%

sparging delivered 103 gravity points which equates to about 8% of the total gravity points obtained during mashing.

However one has to realise this was not a full volume mash so I cannot say what would have happened had I done that. The firgure for the sparging points could have been lower because of the increased reciculating volume.

edit
Looking at the figures I am inclined to think that a full volume mash would deliver much closer to the total gravity points obtained that these calculations would suggest. For example if we take the total points obtained from the 20L mashing volume and compare that to the points obtained from notional volume less grain absorption we see that the sugars held in the grains prior to sparging is only 103 pts ... is it not reasonable to assume if we increase the mash volume to the full 36L liquor volume that these gravity points would have been eluted from the grains by wort recirculation during the 90' mashing period ? I personally am inclined to think that this is very likely.
From what you are saying Jambop when talking Eff most brewers are using Brewhouse as there figures and that is where figures bandied around cause confusion,I would stick to quoting Brewhouse and not mash Eff as some people do not read threads fully and just see the figures and do not realise the difference.
I get nothing less than 75% brewhouse with 3,5l/kilo athumb..
 
So I am not taking sides in debates but I do keep quite comprehensive details of my brews.
Here are some figures from a recent TT's clone recipe I devised.
Total grain bill 4.83 kg
mash liquor 20.15 L
mash gravity at T90' 1.058 assuming grain absorption @ 0.8 L per kg mash volume = 16.286 so total gravity points = 944.6 but the total liquor volume would yield 1160 pts

sparge liquor 16.25L
volume after sparging = 33.25L @ 1.038 total gravity points = 1263.5 mashing effiency was 84%

sparging delivered 103 gravity points which equates to about 8% of the total gravity points obtained during mashing.

However one has to realise this was not a full volume mash so I cannot say what would have happened had I done that. The firgure for the sparging points could have been lower because of the increased reciculating volume.

edit
Looking at the figures I am inclined to think that a full volume mash would deliver much closer to the total gravity points obtained that these calculations would suggest. For example if we take the total points obtained from the 20L mashing volume and compare that to the points obtained from notional volume less grain absorption we see that the sugars held in the grains prior to sparging is only 103 pts ... is it not reasonable to assume if we increase the mash volume to the full 36L liquor volume that these gravity points would have been eluted from the grains by wort recirculation during the 90' mashing period ? I personally am inclined to think that this is very likely.
Depends on what the lautering efficiency is.
84% mash efficiency x lautering efficiency (average of about 75-77% no sparge) gives a brewhouse efficiency of 63-65%
I can do either. I prefer the involvement, hands on, lack of automation of 3 vessel. Much in the same way as I won't use a bread maker, I'll do it manually. Evidently, it's a rare thing, but I actually enjoy the process of brewing, it's quite relaxing. Others sit cross legged by a babbling brook to reach zen, a trickle of sparge water does it for me.

This appears a serial issue for you.
https://www.thehomebrewforum.co.uk/threads/full-volume-mash.92209/
It is that is the way I mash and if one would take the time to look at other forums one would see the efficiencies those users are achieving. Never seen an 80% apart from BIAB which is a different process altogether.
 
Depends on what the lautering efficiency is.
84% mash efficiency x lautering efficiency (average of about 75-77% no sparge) gives a brewhouse efficiency of 63-65%

Nothing to do with snazzy Germanic word for whatever. The mashing efficiency here is calculated on the basis that I at the end of mashing and sparging the 33.25 L of wort contained 84% of the theoretically available sugars from my grist assuming full conversion of the starches to sugars. For this brew the brewhouse efficiency on the basis of how much of those sugars made it into the fermenter compared to the theoretical figure was 76 % the rest was left in the boiler in the trub.
I think had I done a full volume mash there is a very good chance that I would have managed 80% mashing efficiency.
 
Nothing to do with snazzy Germanic word for whatever. The mashing efficiency here is calculated on the basis that I at the end of mashing and sparging the 33.25 L of wort contained 84% of the theoretically available sugars from my grist assuming full conversion of the starches to sugars. For this brew the brewhouse efficiency on the basis of how much of those sugars made it into the fermenter compared to the theoretical figure was 76 % the rest was left in the boiler in the trub.
I think had I done a full volume mash there is a very good chance that I would have managed 80% mashing efficiency.
I have no doubt you would, my last brew was just over 85% mash efficiency but BH was 64%
 
But.... I've been told no one can't get 80% mash efficiency on an AIO full volume, anyone has said so is pulling my chain.

What a fuckin dick.
 
But.... I've been told no one can't get 80% mash efficiency on an AIO full volume, anyone has said so is pulling my chain.

What a fuckin dick.
Ha Ha true, I very rarely think in mash efficiency, so you got me there. The one that matters at the end of the brew day is BHE.
 
Fundamentally disagree. Poor mash efficiency is indicative of a problem, and can be a result of poor temperature control, pH or water deficiencies. All brewers should aim to get a high mash efficiency. The benefits of a good mash carry through to the final product, good quality wort at each stage of the process. For example, insufficient calcium with limit mash efficiency and yeast performance. With good mash efficiency, low brewhouse efficiency becomes a function of physical losses to trub and dead space, and is easily remedied by extra malt or kit modification.

https://www.oculyze.net/the-role-of-recirculating-mash-efficiency-and-clarity/
 
Fundamentally disagree. Poor mash efficiency is indicative of a problem, and can be a result of poor temperature control, pH or water deficiencies. All brewers should aim to get a high mash efficiency. The benefits of a good mash carry through to the final product, good quality wort at each stage of the process. For example, insufficient calcium with limit mash efficiency and yeast performance. With good mash efficiency, low brewhouse efficiency becomes a function of physical losses to trub and dead space, and is easily remedied by extra malt or kit modification.

https://www.oculyze.net/the-role-of-recirculating-mash-efficiency-and-clarity/
I agree with you it is extremely important, temperature, the temperature being constant throughout the mash, mash pH, crush, and dough in temperature. Still, when you get more experienced it will become second nature to achieve a good mash efficiency.
I am never below 80% so don't even think about it now.
No sparge will always get a good conversion due to the ratio of grist to grain it is the lautering efficiency that is the stumbling block, though in hindsight mine isn't as bad as I thought, I always get 2 extra litres out of a 21 litre batch which I don't account for in the BHE
 
it seems the normal consensus is to crush grains fine to get better efficiency but this is not my experience, in the 70s my father taught me to brew and course crush so the grain is broken and the husk is not ground up, this has always worked for me. I used to get mid 80s MHE with a good sparge until I found out about vorlauf, I built a small pump to hook on the side of my boiler/mashtun with the receiving pipe aimed in the middle of the tun and whirlpool the wort and send the outlet pipe over the basket of grain (raised on a frame out of the wort) until the wort comes reasonably clear, then follow up with a sprinkle sparge. I am not adverse to turning the grain bed to get the sparge through the grain and get consistently well into the 90s MHE. many say this should wash out tannins but I haven't noticed this.
my system is a 40lt boiler through which I rotate a basket of grain in the wort to maintain a constant temperature, I start with 25lt of water, stir the grain well and start it spinning for 60 mins, stir well again and test for starch, I then raise the basket and vorlauf, then set to boil and begin the sparge until I have 32lt add the hops at boil. I generally use the grainfather app to work out brew house efficiency. for me the biggest influence on BHE is the Lauter process not grain crush or mash thickness. in my process the mash is very thick as most of the water is outside my spinning basket and I just need to make sure there are no dough lumps and the grains are saturated, that course crush helps in this respect.
 
my system is mostly home made I only pump once the grain basket has been lifted, the pump picks up from the center of the whirlpool and deposits manually over the top of the grain, that spinning is mainly to try and keep the water temperature even throughout with the aid of an SSD temperature controller
 

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