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

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I have no doubt you would, my last brew was just over 85% mash efficiency but BH was 64%
Where are you losing the 20% of the sugars produced during the mashing phase? My efficiency figure are almost the same brew after brew 80-84% mash and 72-75% brewhouse. The brewhouse figure should improve with the Bz are because of the centre drain much less wort will be left in the kettle... in theory none. With the GF S40 I lose about 1.5 - 2L
 
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.

You are quite correct finer crushed grains do not improve efficiency but they do increase the rate of conversion. The fine crush theory is one punted by BIAB brewers. The husk of the malt grain only needs to be just cracked for full conversion to be achieved. The thing then is getting sugars leached out of the grains. This is one of the reasons I only lightly crush my malt grains and always mash for 90 mins using my AIO the reciculated wort has a greater time to elute the sugars from the grains. If one has the time Partigyling would reveal this point .
 
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.
Can you describe the rotating/spinning of the grain a bit more? I'm having trouble understanding what's happening
 
This is like a honey spinner. There is a a motor mounted on the lid. See the last picture.

I think this makes a lot of sense, like this idea a lot.

Camurri do a similar thing with a stirrer, but I think this is one stage better.
 
Where are you losing the 20% of the sugars produced during the mashing phase? My efficiency figure are almost the same brew after brew 80-84% mash and 72-75% brewhouse. The brewhouse figure should improve with the Bz are because of the centre drain much less wort will be left in the kettle... in theory none. With the GF S40 I lose about 1.5 - 2L
Well, brew house efficiency has to take into account lauter efficiency, even with a good mash efficiency a poor lauter efficiency brings down the BHE. But mine wasn't as bad as I thought. I calculate from wort volume into the fermenter, I stop my wort running into the fermenter at the first signs of any trub entering. Usually at 21 litres, but I pour all the trub into a jug and retrieve another 2 litres of wort which usually I bottle for later use in starters or sometimes pour into the fermenter. I have never adjusted for the extra 2 litres.
So my last batch got BHE of 74% which is good for 'no sparge'
IMG_0174.JPG
 
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.
Not should wash out tannins, could wash out tannins, not noticing doesn't mean they aren't there. A lot of people don't recognise tannins, you could even get to like them. Grain crush, lauter, and mash thickness all contribute to BHE.
If the liquor is outside the spinning grain basket how can the enzymes get in to convert the starch? To me, a spinning grain basket brings to mind a rotor where the liquor can't penetrate because it is eking out due to the flow of a spinning grain basket. A bit like a centrifuge throwing the liquid out. A video of it in action would be good.
 
So my brew today is the third brew where I have done a double pass through the grain mill, again I have a good mash efficiency of 85.61%, and more surprising is the lauter efficiency of 87%! So why is this so? I thought that no sparge would produce a poor lauter efficiency. Comes down to swings and roundabouts I am not diluting my wort, I am extracting as much sugar as possible from the grain I have a loss to grain of 7.2 absorption, giving me the lauter efficiency of 87%. and a BHE of 74.08% . Consistent with the other two double passes.
 
Not should wash out tannins, could wash out tannins, not noticing doesn't mean they aren't there. A lot of people don't recognise tannins, you could even get to like them. Grain crush, lauter, and mash thickness all contribute to BHE.
If the liquor is outside the spinning grain basket how can the enzymes get in to convert the starch? To me, a spinning grain basket brings to mind a rotor where the liquor can't penetrate because it is eking out due to the flow of a spinning grain basket. A bit like a centrifuge throwing the liquid out. A video of it in action would be good.
Foxy is right just because you think you can not taste the tannins does not mean they are not getting washed through with over sparging etc it's just a matter of not enough to be easily detected/or you are used to them.
Wine has tannins introduced deliberately
 
If you can get 80% brewhouse efficiency by full volume mashing with recirculation, then why sparge and risk excess tannins? The pH in the grain basket will never drop below the final wort pH, and not go above mash temperature. No need for a mash out, as the time between mashing and starting the boil is however long it takes to lift the malt out.

Some degree of tannins from malt and hops is part of beers flavour.
 
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Each to their own but I crush my grains very lightly for reasons of recirculation flow and sparge flow which allows good extraction of sugars from the malt. I also believe that having a very fine crush will release more tannins from the crushed husk material that a course crush will. What is very telling for me is that fine brewers do not crush their grains to a fine consistancy. In fact Timothy Taylors say that they only just crack the malt grains and they make the finest beer in the world bar none.
 
Yet interestingly other brewers use hammer mills to pulverise the grains and press the grains post mash to ring out the last sugars.
These are the companies making light lager for the masses.
 
Well I sparge with an AIO, about 8l for a 21l batch. I think I could fit full volume in for the mash (but not all systems would) but I don’t think I could lift the malt pipe afterwards. So then I would have to wait for some wort to drain off to a bucket etc, so not really more convenient.
 
Yet interestingly other brewers use hammer mills to pulverise the grains and press the grains post mash to ring out the last sugars.
These are the companies making light lager for the masses.

There may be brewer in some places that do such things ... fotunately not in The UK ... it is an American problem. If you want to drink **** like that dink Interbrew where profit is king if you want to drink proper beer choose brewers who know what they are doing a la Taylors , Harveys, Smiths I could go on but really good beer is not made via a hammer mill
 
Very interesting thread.
It seems I have now done over 200 brews using 2 GF 30 systems and having cocked up (JUST SO) many times and in many different ways, many of which involved jugging wort from one container to another, recoding BHE using BrewMate software and even learning some stuff on the way, somewhere in the low 80's efficiency is dead easy with a GF.

Here are the tips:
The efficiency sweet spot for the GF 30 is 4,5 to 5kg
Take 20m doughing in
Sparge slowly and long - I go for 25L min in the FV
Put the malt pipe on top of a second collection vessel and even put a further litre though the grains. I add table sugar to many beers and this wort will help dissolve it.
At the end of the boil (now 35mins) transfer all the wort to the sparge vessel, through a BIAB bag,
Remove the BIAB bag with the hop / malt debris and give it a good squeeze (as the wort is near boiling, proper PPE gloves are needed here)
Transfer all the wort back to the GF and proceed as usual.

Messing around with the wort transfer adds ~ 10 mins, but because the chilling is on debris free wort, it is the case that not having to constantly compare temps to get the cooling water at the right rate means that it is a time and stress saver in the end.
 
The efficiency sweet spot for the GF 30 is 4,5 to 5kg

Take 20m doughing in

Sparge slowly and long - I go for 25L min in the FV

Thanks, interesting to hear what's worked out in best in long term.
If you ever brew with high % wheat or rye malts, do you change your process?

Sweet spot - is figure the total grain weight?

Is 20min 'doughing in', the time for grain bed rest without recirculation?

Could 25L min, be say either 25L x 1 min duration, or 12.5L x 2 min?
 
So my brew today is the third brew where I have done a double pass through the grain mill, again I have a good mash efficiency of 85.61%, and more surprising is the lauter efficiency of 87%! So why is this so? I thought that no sparge would produce a poor lauter efficiency. Comes down to swings and roundabouts I am not diluting my wort, I am extracting as much sugar as possible from the grain I have a loss to grain of 7.2 absorption, giving me the lauter efficiency of 87%. and a BHE of 74.08% . Consistent with the other two double passes.
It gets better. I didn't get 2 litres from the kettle, I got 3! I bottled the wort from the kettle this morning so the efficiency values go up again. Not that I will be altering anything in my brewing profile, I am happy just to get a couple of litres extra for starters.
1705296829195.png
 
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

I like this. It has given me a idea.
I ferment in my kettle. After overnight cooling, I pitch my yeast.

Do you think pumping over like you do (but into a filter) would add to clarity and also aerate at this stage?
 
Interesting that you mention 20 minute mashout. ........ Time spent at 75-76C at the end of the mash can be included in the total mash time since the enzymes have already done the bulk of the work prior, while much of the alpha still remains. But I doubt there is magic at the mashout temperature of 75C or so .
..... mash temperatures (say 64-73C), then all that really matters is the total time spent in that range..........

I'm doing the mashout step, more to reduce wort viscosity, rather than trying for more sugars.

Also now seeing that total time in range, could be a much easier way to go:
Now I'm using a Bluetooth probe thermometer, I'm seeing that the grainbed temperature typically lags 15 - 30 minutes behind AIO reported temperature (from built in sensor, in heater-base) depending on recirculation rate.

So prior to using BT probe, the mash must have been much cooler overall, yet I was getting good brews. But recently, a few brews have seemed much too high in dextrins, so guessing that the overall temperature, is now too high.

I'm now wondering if the 'recommended' temperatures, that came from before the time of accurate probe thermometers, are actually too high??
 
Are you saying that 1000's of years brewing knowledge have been succeeded by a cheap Chinese thermometer.

I will accept they may have a plan to take over the world but this was really how I envisioned it. 😁 One beer at a time.

Brewtoof secret leapon 😁
 
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