Low efficiency-should I sparge with more water?

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Tricky Dicky

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I am partial mashing 3kg grain BIAB in a 19L pot and I add DME to the boil as required in order to meet my required OG as per Beersmith. I aim to brew 19L batches and use recipes in conjunction with Beersmith to achieve this.

I mash in for 60 mins ( my temperature holds well and tends to be 66c for the beers I brew) in 9L and end up with 12L after sparging 3L through the grain ( I also mash out for 15 mins at 75C). I boil the 12L and add 3L of frozen water after the boil to cool down the wort (can’t invest in a cooling coil at the moment) and then liquor back until I reach my target OG which normally takes me to around 17 or 18 litres. Which I think means that my efficiency is not where it should be according to Beersmith.

So could I increase the efficiency by sparging more water, is 3L enough? is there a limit ?or should I mash with more water or maybe increase mash time or is there something else I could do besides adding more DME in order to reach my OG for 19L?
 
what efficiency do you have it set to ?

I'm semi new. have done 14 BIAB AG batches in the last year after 4 or 5 years of kits . I get 75% efficiency in the kettle ending setting .I see all these recipes where people use 80% or 85% brew house efficiency into the fermenter and wonder if people bump their numbers up for the ego at times . maybe they are just better than me. quite possible. I do full volume mash. so don't sparge

a kg of grain is cheap. if you arnt hitting your numbers just add another kg
 
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So could I increase the efficiency by sparging more water, is 3L enough? is there a limit ?or should I mash with more water or maybe increase mash time
Yes you could sparge with more water or mash full volume, or at least up to whatever you can get in to your 19L pot without it boiling over. Obviously you then couldn’t use ice to get the temp down but would no chilling in a 20L cube be an option for you? Increasing mash time may also help.

Edit: Forgot to add that though you could try the above it may not increase your efficiency significantly particularly in a BIAB partial mash.
 
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Efficiency is what it is. Adding more water just dilutes what you have extracted. It will give you no increase.
10 litres @ 1.040 is the same efficiency as 20 litres @ 1.020.
You need to look elsewhere to increase efficiency, such as the quality of your crush, how you collect your runnings from your mashtun, the deadspace in your mashtun, whether you do a mashout temperature addition, how you sparge etc etc.

I know you said you BIAB, but much of it still applies.
 
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Efficiency is what it is. Adding more water just dilutes what you have extracted. It will give you no increase.
10 litres @ 1.040 is the same efficiency as 20 litres @ 1.020.
You need to look elsewhere to increase efficiency, such as the quality of your crush, how you collect your runnings from your mashtun, the deadspace in your mashtun, whether you do a mashout temperature addition, how you sparge etc etc.

I know you said you BIAB, but much of it still applies.
I do a mash out already and I'm only adding water by sparging water through the bag of grain which I thought collected more fermentable?
 
what efficiency do you get, and what are you aiming for?

personally I'd just add a handful more grain...
I'm probably not measuring efficiency the proper way but I'm plugging into Beersmith my recipes and it predicts an OG for the final volume of beer. So after I've boiled the wort and cooled it down I take a reading of the OG and then liquor back according to the OG reading i.e adding one litre of water drops the OG by 2 points I do this until I reach my target OG (as predicted by Beersmith) But more often than not unless I want weaker beer I end up liquoring back to only the 17 or 18 litre level and not 19 litres.
 
Yes you could sparge with more water or mash full volume, or at least up to whatever you can get in to your 19L pot without it boiling over. Obviously you then couldn’t use ice to get the temp down but would no chilling in a 20L cube be an option for you? Increasing mash time may also help.

Edit: Forgot to add that though you could try the above it may not increase your efficiency significantly particularly in a BIAB partial mash.
The reason I don't mash at higher volumes is according to my understanding once you have boiled the wort you need to reduce the temperature as rapidly as possible. If I have 19L of hot wort and can't afford a chiller coil right now, how would I cool 19L rapidly?
 
The reason I don't mash at higher volumes is according to my understanding once you have boiled the wort you need to reduce the temperature as rapidly as possible. If I have 19L of hot wort and can't afford a chiller coil right now, how would I cool 19L rapidly?
Though it is best to chill asap it is not strictly necessary. If you search for no chill on this forum there is plenty info on the method. It was made hugely popular here on AHB years ago when a couple members of the Illawarra Brewers Union started doing and posting about it. It’s the same way as fresh wort kits in LHBS are done.

After re reading your op I see you are only sparging with 3 kg grain with 3L so yes a longer sparge should help.

If you don’t have a chiller but have a cube or can get one give it a go. Some brewers actually prefer to do it rather than chill as they can leave it in the cube until they want to ferment it. Some keep the wort months and even years before pitching yeast.
 
Maybe Re calculate your boil off rate. Adjust this in brewsmith. Also what as mongey said do you have your efficiency set to. I’m a biaber and have mine set to 65% which seems to hit the marks most times (looks like I might have look and tweak some stuff to get what mongey gets!).
 
There are a few fundamental misconceptions being bandied about above.
Firstly
The L:G makes a big difference, as does your grind, temperature, mash time... everything you do contributes to how much extract you collect and to the quality of that extract. Its quite possible to make more beer from a grain bill and in the process to make it pretty shabby beer by extracting things we don't want. So efficiency isn't the be all and end all of brewing, I suppose its fair to say that its good to get as much good beer as we can, well its cheaper and I for one hate unnecessary waste.
If we look at no sparge and just for the sake of discussion make a few assumptions - the grain bill has a potential of 77%, we loose 0.8L/kg of grist, it takes about 2L/kg (L:G of 2:1) to cover the malt with water.
There is an equation that tells us pretty precisely what the gravity will be, its
oP first runnings = Potential (as a percent)/L:G+Potential
So say we mashed in the 3kg above in 9L of water the oP of the sweet water would be 0.77/(3.77)=0.204 or 20.4oP or 1.082 if you prefer.
As the grain absorbs 2.4L we would collect (9-2.4)=6.6L
We started with 3kg of malt so the theoretical yield would be (3*0.77)=2.31kg.
We got from, mass extract = Volume *SG*oP = 6.6*1.082*0.204=1.457kg
Your efficiency would be 1.457/2.31=0.63 or 63%
Here is the same calculation for 2-7:1 L:G
upload_2019-4-25_12-34-25.png


Just heading off to the pub for a couple of ANZAC Ales, so will stop there but its pretty clear that your L:G makes a pretty big difference.
Mark
 
There are a few fundamental misconceptions being bandied about above.
Firstly
The L:G makes a big difference, as does your grind, temperature, mash time... everything you do contributes to how much extract you collect and to the quality of that extract. Its quite possible to make more beer from a grain bill and in the process to make it pretty shabby beer by extracting things we don't want. So efficiency isn't the be all and end all of brewing, I suppose its fair to say that its good to get as much good beer as we can, well its cheaper and I for one hate unnecessary waste.
If we look at no sparge and just for the sake of discussion make a few assumptions - the grain bill has a potential of 77%, we loose 0.8L/kg of grist, it takes about 2L/kg (L:G of 2:1) to cover the malt with water.
There is an equation that tells us pretty precisely what the gravity will be, its
oP first runnings = Potential (as a percent)/L:G+Potential
So say we mashed in the 3kg above in 9L of water the oP of the sweet water would be 0.77/(3.77)=0.204 or 20.4oP or 1.082 if you prefer.
As the grain absorbs 2.4L we would collect (9-2.4)=6.6L
We started with 3kg of malt so the theoretical yield would be (3*0.77)=2.31kg.
We got from, mass extract = Volume *SG*oP = 6.6*1.082*0.204=1.457kg
Your efficiency would be 1.457/2.31=0.63 or 63%
Here is the same calculation for 2-7:1 L:G
View attachment 115562

Just heading off to the pub for a couple of ANZAC Ales, so will stop there but its pretty clear that your L:G makes a pretty big difference.
Mark
Thanks for that Mark, I'll bump up my mash volume to 12L and sparge with 4L water and see how that goes.
 
Good step in the right direction, you will get more extract if you "batch sparge" (soak the malt in the 4L hot (<80oC) water).
Remembering that a lot of the lost extract is still inside the grist, not just between the bits of malt (that's easy enough to get at) but it takes time for the sugars to migrate out of the grist. Somewhere between 15-30 minutes should get a fair fraction into solution.
Just pouring hot water over the grain in the bag is very inefficient, it tends to flow around the outside, rather than through the grist. Batch sparging is way better.
You wont lose the 0.8L/kg a second time, if you added the bag and your 4L sparge, you should get 4L back.
Just a rough calculation I would expect around 13.5L at ~1.050, comes to about 78% efficiency.
Mark
 
Good step in the right direction, you will get more extract if you "batch sparge" (soak the malt in the 4L hot (<80oC) water).
Remembering that a lot of the lost extract is still inside the grist, not just between the bits of malt (that's easy enough to get at) but it takes time for the sugars to migrate out of the grist. Somewhere between 15-30 minutes should get a fair fraction into solution.
Just pouring hot water over the grain in the bag is very inefficient, it tends to flow around the outside, rather than through the grist. Batch sparging is way better.
You wont lose the 0.8L/kg a second time, if you added the bag and your 4L sparge, you should get 4L back.
Just a rough calculation I would expect around 13.5L at ~1.050, comes to about 78% efficiency.
Mark
So if I liquor back to 19L I'd get approx 1039 OG?
 
If by "liquor back" you mean dilute then I get closer to 1.0355
C1V1=C2V2, remember that you cant use 1.050 as its what we call non unitary (its not a quantity its a comparison to the density of water) use oP or points.
in points: - 13.5*50=19*C2 = 13.5*50/19 = 35.5, or 1.0355
in oP: - 13.5*12.5=19*C2 = 13.5*12.5/19 = 8.88oP or 1.0355

If you used SG as a number you get
(13.5*1.050)/19=0.74 which doesn't make any sense at all.
Mark
 
If by "liquor back" you mean dilute then I get closer to 1.0355
C1V1=C2V2, remember that you cant use 1.050 as its what we call non unitary (its not a quantity its a comparison to the density of water) use oP or points.
in points: - 13.5*50=19*C2 = 13.5*50/19 = 35.5, or 1.0355
in oP: - 13.5*12.5=19*C2 = 13.5*12.5/19 = 8.88oP or 1.0355

If you used SG as a number you get
(13.5*1.050)/19=0.74 which doesn't make any sense at all.
Mark
So now I'm thinking that I have been looking at the wrong Estimated OG in the Beersmith design page, I have used the "Est Original Gravity" field on the left under the "Beer Style Guide Comparison" which moves up and down depending on the amount of fermentables in your recipe. Maybe I should be using "Est Pre-Boil Gravity" over on the right (where you can choose the fields you'd like displaying) ?
Also if I understand the equation correctly if I'd like the OG to be 1.042 at 19L my OG at 15L needs to be 1.0532 ?
 
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Good step in the right direction, you will get more extract if you "batch sparge" (soak the malt in the 4L hot (<80oC) water).
Remembering that a lot of the lost extract is still inside the grist, not just between the bits of malt (that's easy enough to get at) but it takes time for the sugars to migrate out of the grist. Somewhere between 15-30 minutes should get a fair fraction into solution.
Just pouring hot water over the grain in the bag is very inefficient, it tends to flow around the outside, rather than through the grist. Batch sparging is way better.
You wont lose the 0.8L/kg a second time, if you added the bag and your 4L sparge, you should get 4L back.
Just a rough calculation I would expect around 13.5L at ~1.050, comes to about 78% efficiency.
Mark
Hi Mark I just mashed 3kg grain with 12L at 66c to recipe and batch sparged with 4L water for 30 minutes. Mate, it worked a treat, I hit the expected OG 1044 and 20.5 L as per Beersmith expectations after liquoring back, best efficiency I've had so far by a mile! Cheers and thanks for your help :)
 
First your welcome.
Second that's a pretty good yield (~78%) I wouldn't try to push for too much more, acidifying your sparge (just a couple of mL of Lactic acid) would prevent any tannin pickup.
Luck with your brewing, worth remembering that the science of brewing is on your side, understanding processes helps you control your outcomes.
Mark
 
Time will tell of course but would this improvement to my process also result in better tasting beer? and would it make any difference to the attenuation rate?
 
Provided you don't start extracting tannins from the husks, It shouldn't change the flavour much, just give you more good beer.
Adding minerals and acid, or at a minimum treating it the same as your mash water is a good start.
Mark
 

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