Efficiency query - not hitting target

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Hi All,
A general query regarding hitting efficiency and looking for any tips on how I can improve mine. Please note that I am not looking to try and hit any high numbers, I'm just looking for advice so I can hit around 70%!!

My current set-up is basically a BIAB system, full water volume (thus no sparge) - I have a digiboil I use to mash/brew in. I recently upgraded this system by purchasing the grain basket (malt pipe?) and making a recycling pump, thus in effect having an all-in-one setup. I am happy with how this is going and the couple of brews I've done with this new set-up have been fine. Before upgrading I was usually a few points below my target S.G., with an efficiency around 68-70%. Post improvements, this hasn't changed. I was hoping that recirculating my liquids would increase efficiency slightly, but I put not seeing any change down to getting the set-up working efficiently.

However, today I brewed by attempt at an Imperial Stout - 12L brew. The increase in the grain bill was naturally quite significant compared to previous brews, and this may have resulted in a substantial drop in efficiency. I noticed during the mash that water wasn't filtering through the grain bed as normal and it was backing up. I left the mash for 30 mins longer and kept stirring. My pre-boil gravity was approx. 20points short (1.055 rather than 1.075). I've never had that big a difference before! The total water volume for this brew was 21L, and I'm thinking that this was an issue in hitting my pre-boil target? For the first time ever I checked my pH - I only have strips to use but it came in around 5.4. So I'm not too concerned about that (having read that a pH from 5.0-5.6 is fine). I guess sparging would improve things, but this isn't an option for me. The other issue I have with my set-up is that the malt pipe sits on a stand in the boiler, thus there is about 5-7l water below the grain level (thus recirculating). Maybe this is having a bigger impact than I expected, especially when the grain bill is bigger? For this brew I ended up having to add some sugar to get near my S.G which wasn't ideal.

I am planning to make my Trappist brew next (2-3 weeks time) for the Brew like a monk comp, and I'd like any suggestions (if possible) so I can reduce this issue next time. Naturally I'll change my profile setting in the App to take my lower efficiency into account (probably going to put this at 65%), but would anyone have any tips on something I have overlooked on this? The grain is pre-milled, and maybe that is an issue. I am using Crisp pale M.O and maybe I need to mix the grain before weighing out, just in case the flour has settled to the bottom of my container?

This is more of a frustration than a major issue - I'm curious where things have gone wrong today. Thanks in advance.
 
I would have expected recirculation trip improve your efficiency a bit over BIAB. Odd that it didn't. The 5-7L underneath your grain bed shouldn't make that much difference if you're recirculating (provided the inlet for the pump is drawing in this liquid and not the wort from just below the bottom of the grain bed).

If you've had problems with recirculation, then more stirring may help. Otherwise there's a chance you're getting channeling in the grain bed and not getting an even extraction. You should find that if you give it all a good stir between 5 and 15 minutes into the mash, the recirculation improves quite a bit. I do this a lot now.

How much wort is left behind in the kettle when you transfer to the fermenter (ie, dead space). The grainfather I use is about 2L, but the bigger this volume, the lower your (brewhouse) efficiency as this is sugary wort you're leaving behind.

Sparging will definitely improve your efficiency a little bit not hugely.

Higher OG beers end up with a lower efficiency, as do smaller batches. When I brew strong Belgians, I drop the efficiency from 80% to about 70%
 
I would have expected recirculation trip improve your efficiency a bit over BIAB. Odd that it didn't. The 5-7L underneath your grain bed shouldn't make that much difference if you're recirculating (provided the inlet for the pump is drawing in this liquid and not the wort from just below the bottom of the grain bed).

If you've had problems with recirculation, then more stirring may help. Otherwise there's a chance you're getting channeling in the grain bed and not getting an even extraction. You should find that if you give it all a good stir between 5 and 15 minutes into the mash, the recirculation improves quite a bit. I do this a lot now.

How much wort is left behind in the kettle when you transfer to the fermenter (ie, dead space). The grainfather I use is about 2L, but the bigger this volume, the lower your (brewhouse) efficiency as this is sugary wort you're leaving behind.

Sparging will definitely improve your efficiency a little bit not hugely.

Higher OG beers end up with a lower efficiency, as do smaller batches. When I brew strong Belgians, I drop the efficiency from 80% to about 70%
Thanks for that. My tap is probably and inch or two above the base so there may be some liquid not getting recirculated, but not sure if that makes a big difference. Hadn't thought about that issue. It may just be down to the mash thickness. I was in there a lot stirring and I also kept changing the location of the inlet pipe, so hopefully minimised channelling. I may just have to keep this in mind for higher abv brews. At the end of the boil I tend to tip the boiler to get most of the wort, only leaving a small volume behind. I can never decide if that's a good plan, but the beer always comes good. Cheers.
 
Thanks for that. My tap is probably and inch or two above the base so there may be some liquid not getting recirculated, but not sure if that makes a big difference. Hadn't thought about that issue. It may just be down to the mash thickness. I was in there a lot stirring and I also kept changing the location of the inlet pipe, so hopefully minimised channelling. I may just have to keep this in mind for higher abv brews. At the end of the boil I tend to tip the boiler to get most of the wort, only leaving a small volume behind. I can never decide if that's a good plan, but the beer always comes good. Cheers.
OK, so it doesn't sound like the deadspace at the bottom is a problem then. Tipping the boiler - lot of people do this. You get more wort out, with a bit more trub. Different people have different opinions on it, but given that's a different topic let's leave that for a different thread ;) .
 
OK, so it doesn't sound like the deadspace at the bottom is a problem then. Tipping the boiler - lot of people do this. You get more wort out, with a bit more trub. Different people have different opinions on it, but given that's a different topic let's leave that for a different thread ;) .
Lol ..yes that one can stay filed away with the 60 v 30 min boil time 😂😂
 
I think your issue may be the no sparge process and having you malts milled for you. Especially as the malt bill increases.

Any way you can add a small sparge? Another idea may be to do a mashout for 15 minutes and add as much water as you can, that sometimes helps with efficiency.
 
I think your issue may be the no sparge process and having you malts milled for you. Especially as the malt bill increases.

Any way you can add a small sparge? Another idea may be to do a mashout for 15 minutes and add as much water as you can, that sometimes helps with efficiency.
Hi Pennine....for a moment I had an Eureka moment, but having thought about it I'm not sure🤔. So your comment about adding more water made me think if I'd misread the volume needed from my app. I had taken the vol + mash vol as total water - 21l for this brew. Under that on the app is total mash vol (22.06l). I thought maybe I was 1l less than needed, but thinking about it I'm not sure now if I'm thinking this correctly. I have, however, noticed that I had the wrong setting on the app. If I change the profile to BIAB no sparge, the starting vol changes to around 18.5l. would having less water result in higher gravity? I'm thinking...I'm not sure anymore 😂. I would have had a thicker mash so maybe more problems? Maybe taking the total mash vol of just over 22l may have been better? Either way, I think I've used the wrong profile in calculating things on this brew, and I haven't appreciated increased absorption due to the significant increase in the grain bill

I did undertake a mash out to hopefully improve efficiency, but unfortunately it didn't help this time. I think for my next brew I'm going to go back to using my bag rather than using the malt pipe (as the next one will also have an increased grain bill, but not as much), then experiment again with the malt pipe on a normal bitter. I'd love to go down the road of milling my own grain...maybe in a few years time when I have negotiated a bigger brewing space 🤔😂😂 Cheers.
 
Consistency is more important than higher numbers.
Yes, I agree. I didn't phrase my initial message very well, but it was more on suggestions on where I went wrong today as my efficiency took a nose dive compared to previous brews!! Think it's down to the grain bill, my method and an incorrect profile setting - tho mainly the first two!! I'm generally within a few points of predicted gravity which I'm happy with....today I was miles off. The wort tasted great tho when sampling👍
 
If I change the profile to BIAB no sparge, the starting vol changes to around 18.5l. would having less water result in higher gravity? I'm thinking...I'm not sure anymore 😂. I would have had a thicker mash so maybe more problems? Maybe taking the total mash vol of just over 22l may have been better?

Generally, yes if you've used too much liquor then the wort will have been diluted. Did you end up with more wort into the fermenter than expected (accounting for other losses with the new setup?)

I FVM and use the BIAB mash profile in Beersmith and am usually spot on numbers, or thereabouts. Sometimes I'll do a small (1/2l) sparge but take that from the full liquor volume so I don't dilute the pre-boil gravity. I'm not sure it makes much of a difference but is very little effort and *seems* like an assurance step.

I wouldn't be concerned about too thick mashes with FVM, even with Imperial strength beers. However, conventional wisdom is that higher gravity worts do take an efficiency hit (wort sugar saturation, perhaps?)

70% mash efficiency should be more than achievable with FVM in a recirculating all-in-one.

Fine tune your numbers in your software through experience and your consistency will come I'm sure.
 
You using different grain?

I've been having efficiency issues for the past few months. I had been hitting 80-85% doing biab and was down to 65-70%.

Last batch I started a new lot of grain. Efficiency that batch was 82%..
 
conventional wisdom is that higher gravity worts do take an efficiency hit (wort sugar saturation, perhaps?)
It's not saturation. A huge amount of sugar can dissolve in a small amount of water (SG 1.330 from a quick Google).

It's more to do with concentrations gradients of the sugar in the wort and the grain. If you have a high concentration of sugar in one place (the grain) and a low concentration in another (the liquor/wort), then the sugar will follow from high to low until equilibrium is reached. The higher the difference in concentration (the gradient) the faster the sugar will move from high to low concentration. This is why we sparge with fresh liquor.

If you are brewing a high gravity beer, the wort is a higher gravity , so the equilibrium point (where sugar stops being extracted from the grain) is higher, and it is extracted more slowly. Hence there is more sugar left in the grain at the end of the sparge and your efficiency is lower
 
Generally, yes if you've used too much liquor then the wort will have been diluted. Did you end up with more wort into the fermenter than expected (accounting for other losses with the new setup?)

I FVM and use the BIAB mash profile in Beersmith and am usually spot on numbers, or thereabouts. Sometimes I'll do a small (1/2l) sparge but take that from the full liquor volume so I don't dilute the pre-boil gravity. I'm not sure it makes much of a difference but is very little effort and *seems* like an assurance step.

I wouldn't be concerned about too thick mashes with FVM, even with Imperial strength beers. However, conventional wisdom is that higher gravity worts do take an efficiency hit (wort sugar saturation, perhaps?)

70% mash efficiency should be more than achievable with FVM in a recirculating all-in-one.

Fine tune your numbers in your software through experience and your consistency will come I'm sure.
Hi, thanks for your reply. I ended up with less wort, tho that was down to boiling more vigorously than normal to get the gravity up. I think I had the expected vol after the mash (around 16.5l). I have 10l in the FV than the expected 12l. Cheers.
 
You using different grain?

I've been having efficiency issues for the past few months. I had been hitting 80-85% doing biab and was down to 65-70%.

Last batch I started a new lot of grain. Efficiency that batch was 82%..
Yes, I have used a different grain for the last few brews. I did read someone else having a change in efficiency with a different sack. Maybe a factor as well, but I'm also wondering if I have uneven mixing in my grain barrel. Will try and mix it a bit for the next brew. 👍
 
Hi All,
A general query regarding hitting efficiency and looking for any tips on how I can improve mine. Please note that I am not looking to try and hit any high numbers, I'm just looking for advice so I can hit around 70%!!

My current set-up is basically a BIAB system, full water volume (thus no sparge) - I have a digiboil I use to mash/brew in. I recently upgraded this system by purchasing the grain basket (malt pipe?) and making a recycling pump, thus in effect having an all-in-one setup. I am happy with how this is going and the couple of brews I've done with this new set-up have been fine. Before upgrading I was usually a few points below my target S.G., with an efficiency around 68-70%. Post improvements, this hasn't changed. I was hoping that recirculating my liquids would increase efficiency slightly, but I put not seeing any change down to getting the set-up working efficiently.

However, today I brewed by attempt at an Imperial Stout - 12L brew. The increase in the grain bill was naturally quite significant compared to previous brews, and this may have resulted in a substantial drop in efficiency. I noticed during the mash that water wasn't filtering through the grain bed as normal and it was backing up. I left the mash for 30 mins longer and kept stirring. My pre-boil gravity was approx. 20points short (1.055 rather than 1.075). I've never had that big a difference before! The total water volume for this brew was 21L, and I'm thinking that this was an issue in hitting my pre-boil target? For the first time ever I checked my pH - I only have strips to use but it came in around 5.4. So I'm not too concerned about that (having read that a pH from 5.0-5.6 is fine). I guess sparging would improve things, but this isn't an option for me. The other issue I have with my set-up is that the malt pipe sits on a stand in the boiler, thus there is about 5-7l water below the grain level (thus recirculating). Maybe this is having a bigger impact than I expected, especially when the grain bill is bigger? For this brew I ended up having to add some sugar to get near my S.G which wasn't ideal.

I am planning to make my Trappist brew next (2-3 weeks time) for the Brew like a monk comp, and I'd like any suggestions (if possible) so I can reduce this issue next time. Naturally I'll change my profile setting in the App to take my lower efficiency into account (probably going to put this at 65%), but would anyone have any tips on something I have overlooked on this? The grain is pre-milled, and maybe that is an issue. I am using Crisp pale M.O and maybe I need to mix the grain before weighing out, just in case the flour has settled to the bottom of my container?

This is more of a frustration than a major issue - I'm curious where things have gone wrong today. Thanks in advance.
Its a misconception that the return pipe will result in higher efficiency, its all the same liquor so will extract the same amount of sugar even without a return pipe. The purpose of the return pipe is to keep the temperature even (theoretically) That is what stirring does, it reduces the hot and cool spots that will keep the temperature on a more even keel.
As the ratio of grain goes up against the ratio of the liquor you will send the efficiency down, once you go over a 5% ABV beer the efficiency goes down with every point above the 5%, whether you sparge or not.
That is the reason before sparging was ever thought of there would be first and second runnings even 3rd and 4th in some cases. (Parti Gyle
Even using a Hoch Kurz mash while you may convert more of the starch, the sugar still has to be extracted from the grain at the end of mashing.
Reiterated mashing is probably the best option for a home brewer to brew an Imperial stout or any big beer.
https://byo.com/article/reiterated-mashing-multiple-mashes-for-massive-brews/
 
Consistency is more important than higher numbers.
This. Efficiency is irrelevant at homebrew level...just get your process down so it is consistent and repeatable and accept whatever efficiency you have. The only downside to lower efficiency is a few more pence/cents of additional grain. Its important in a commercial setting where saving a few percent of cost per batch adds up over the year and hundreds of batches, but for us homebrewewgrs efficiency is a long way down a very long list of things to focus on and master.


I agree with Foxy on reiterated mashing. I've used it a couple of times but even then struggled to achieve more than 1.090 against a 1.100 target OG in a 10 litre batch in my 30 litre Brewzilla. Think you're just pushing these small homebrew setups a bit too much in these scenario's.
 
I managed to increase my efficiency by 15 points by performing a crude lautering at the end of the mash, I made a frame and basket to hold the grain above the wort and a 12v pump to take the wort from the bottom centre to flow over the grain bed, this allows me to whirlpool the wort and clean out residual grain, I also stir the grain bed at the start of lautering and keep the lauter going until the wort runs clear, my brews are 30lt and I sparge 10lt but I believe the Lauter process gives me the best improvement. I constantly get 95 percent.
 
I managed to increase my efficiency by 15 points by performing a crude lautering at the end of the mash, I made a frame and basket to hold the grain above the wort and a 12v pump to take the wort from the bottom centre to flow over the grain bed, this allows me to whirlpool the wort and clean out residual grain, I also stir the grain bed at the start of lautering and keep the lauter going until the wort runs clear, my brews are 30lt and I sparge 10lt but I believe the Lauter process gives me the best improvement. I constantly get 95 percent.
Is that like the mash recirculation that grainfather all in ones do? I don't have such a thing nor do I recirculate my mash except for a few jugfuls at the end. Interested to understand why they do that.
 
Is that like the mash recirculation that grainfather all in ones do? I don't have such a thing nor do I recirculate my mash except for a few jugfuls at the end. Interested to understand why they do that.
not sure what the grain father does, never used one, I just use a 40lt boiler as a mash tun. lautering basically washes out the sugar from the grain bed whilst filtering out the husk etc from the wort, I stir up the grain bed first then rebuild the bed as I run the wort through it, I pick up from the center of my tun and whirlpool as it runs, it gets most of the sugars out of the grain, a sparge gets most of the rest out, and leaves the wort nice and clear, very little sugar left in the grain when I have finished. my last brew made 1.051 from 4.75kg of fermentables in a total of 29lt
 
This is just an update to my initial issue. I brewed a Belgian Dubble today and hit my numbers nicely. It seems that my issue was simply not having the correct profile settings on the brewfather app. Having set that correct for a BIAB no sparge (efficiency automatically set to 69%), I was just 1pt off my OG 🎉. I ended up 1.5l short, but I realised I had forgotten to add the last of the wort runoff from the grain basket into the boiler (1l left behind). I'll find the other 0.5l another day 😂.
 

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