Another poor brewhouse efficiency question

[DanMalleck]

Hi everyone
I’ve been brewing all grain for 12 years now and probably should have nailed my process by now. But I took some time off and am currently brewing smaller batches (3Gal) until I get my brewing mojo back. (long story no point going over it now)

The problem is no matter what I do my numbers are off. My efficiency is about 55%; my OG and FG are lower than expected, and everything is just…. Wrong

I could use some suggestions
I am using a 5 gal cooler with one of those DIY braided hoses as a filter. I grind my grains myself, and moisten the base grain before grinding so I get lots of husks to make a nice grain bed/filter. I get a pretty fine crush but not flour!

I picked up a decent ph meter so I have been keeping an eye on my ph and it matches the brewsmith estimations. Normally 5.5 or thereabouts. I have added lactic acid and baking soda (depending on which way I need to adjust the ph) and apart from one mess up the first time I use the meter it seems to have gone ok (to be clear I don’t make a ph adjustment while mashing since I know that by the time I get a decent reading it’s too late; I make my adjustements in the water before mashing)

I also stir vigorously when mashing and let er sit. The temp has held well where I need it.

I used to fly sparge but now in order to try to address the efficiency thing I turned to batch sparging. I use Brew Smith’s calculations for how much water to use but normally increase it a touch because my final volumes have been lower than I want. I mash, check the conversion with an iodine test, recirculate until clear, drain the tun, add the sparge water, stir for a bit, let it sit, then drain. Last batch I did I added the sparge water before first drain, but otherwise I normally drain first.

My gravity going into the kettle has routinely been about 10 points below expected, although my final gravities have been about what was expected give or take a few points.
Final volume has normally been about 1/2 gallon below expected and gravity has been off by 10-15 points.

Ok, so any suggestions? This is very frustrating. I mean, the beer hasn’t been terrible, but I would Ike to be able to hit the numbers a little better. (Btw I’ve been working on some basic batches, like a bitter or pale ale, so not a lot of complicated ingredients)

 

[Airborneguy]

I’m going through the same problem. After an 8 year hiatus, I jumped straight back into all grain. My beers have been tasty, but I am missing the gravity mark badly, every time.

Today I missed a hefe by nearly 20 points.

I think I know my problems: trusting online retailers with the crush, and over-shooting volume. I’m planning to measure my pre- and post- boil volumes much more accurately starting with my next batch.

From your description, volume could be one of your issues as well. How sure are you of those calculations?

 

[doug293cz]

In order to diagnose efficiency problems, the following data is needed:

• Grain bill details
• Strike water volume (actually all water added before end of mash)
• Sparge water volume
• Sparge process (fly, batch, or none, and if batch, how many sparge steps)
• SG of wort at end of mash, prior to run-off (should be after thorough stirring or thorough vorlauf)
• Pre-boil volume and SG (after thorough mixing of initial and sparge wort)
• Post-boil volume and SG (i.e. OG)
• Volume to fermenter

With this data it is possible to determine conversion efficiency (how well the mash worked), lauter efficiency (how well you separated sugar formed from the grain), mash efficiency (conversion efficiency * lauter efficiency), and brewhouse efficiency (which is less interesting than mash efficiency, since it is just mash efficiency * fermenter volume / post-boil volume.)

Conversion efficiency is primarily determined by crush fineness, mash time, and to a lesser extent by mash pH. Lauter efficiency is primarily determined by sparge process and grain absorption rate. Brewhouse is determined by the previous two, plus how much wort you leave behind going from BK to fermenter.

Measurement accuracy is critical, as the calculated efficiency can be no more accurate than the worst measurement that goes into the calculation. Volumes must be measured volumes, not target volumes, and should be measured to an accuracy of 0.1 gal (for a 5 gal batch.)

Without the above data, anything said about poor efficiency is just speculation.

Brew on

 

[IslandLizard]

A 5 gallon cooler is probably a bit too small for mashing most 5 gallon batches. With such a small volume, your mash will be really thick, not helping extraction, conversion, and efficiency.
I'd try to aim for a mash ratio of 1.5 at minimum. Meaning, mashing with 1.5 quarts of water per pound of grist.

recirculate until clear

With a pump? Or just pouring cloudy runnings back on the top?

 

[RM-MN]

The biggest factor in efficiency is the quality of the crush. No other factor comes close. Mill finer until you get a stuck mash and your efficiency should rise, then open the mill just a little so you don't get a stuck mash next time. Better yet, replace that braid with a fine mesh bag and mill until you do get flour. With your grains contained in the bag you don't get a stuck mash because the bag forms a huge filter area. If the wort doesn't want to come out by itself you can force it by squeezing the bag.

The next factor in efficiency is how much wort you leave in the kettle at the end of the boil. If you do a whirlpool to leave the trub behind and get clear wort, much of what you leave behind is wort with suspended proteins. Dump it all into the fermenter and let the yeast decide what to leave behind. Give the beer sufficient time to settle out the proteins and a bunch of the yeast so you get clear beer into the bottles/keg.

 

[scrap iron]

Are you sure your thermometer is accurate? You may be mashing higher than you think. The above suggestions about volumes and water to grain ratio measurements are valid to get the right efficiency numbers.

 

[dmtaylor]

Tighten the gap on your mill a little more. The end.

 

[pvtpublic]

I see I potential cause right here;

I mash, check the conversion with an iodine test, recirculate until clear, drain the tun, add the sparge water, stir for a bit, let it sit, then drain. Last batch I did I added the sparge water before first drain, but otherwise I normally drain first.

Draining the tun will compact your grain bed and cause channeling, lowering your efficiency. Even though you stir it back up, the initial draining will exponentially decrease the extraction as the lautering is taking place, as will the second draining. Try to keep some water above the top of the bed so the grain stays suspended, either with a full volume mash or fly sparging.

 

[DBhomebrew]

I see I potential cause right here;

Draining the tun will compact your grain bed and cause channeling, lowering your efficiency. Even though you stir it back up, the initial draining will exponentially decrease the extraction as the lautering is taking place, as will the second draining. Try to keep some water above the top of the bed so the grain stays suspended, either with a full volume mash or fly sparging.

OP has chosen to move from fly sparging to batch sparging. A small hit to efficiency, yes, but simple, predictable, and repeatable.

dennybrew

 

[DBhomebrew]

I picked up a decent ph meter so I have been keeping an eye on my ph and it matches the brewsmith estimations. Normally 5.5 or thereabouts. I have added lactic acid and baking soda (depending on which way I need to adjust the ph) and apart from one mess up the first time I use the meter it seems to have gone ok (to be clear I don’t make a ph adjustment while mashing since I know that by the time I get a decent reading it’s too late; I make my adjustements in the water before mashing)

To be doubly clear, do you adjust water for Batch A based on Batch A pH measurement? Or does a Batch A measurement inform a Batch B adjustment?

 

[DanMalleck]

A 5 gallon cooler is probably a bit too small for mashing most 5 gallon batches. With such a small volume, your mash will be really thick, not helping extraction, conversion, and efficiency.
I'd try to aim for a mash ratio of 1.5 at minimum. Meaning, mashing with 1.5 quarts of water per pound of grist.


With a pump? Or just pouring cloudy runnings back on the top?

Cheers
It's a 3 gallon batch as noted in post.
I don't use a pump I just pour it back in slowly to avoid disturbing the grain bed.

 

[DanMalleck]

Are you sure your thermometer is accurate? You may be mashing higher than you think. The above suggestions about volumes and water to grain ratio measurements are valid to get the right efficiency numbers.

Yes I calibrate it to boiling water before brew because on time it was way off.
Cheers

 

[DanMalleck]

To be doubly clear, do you adjust water for Batch A based on Batch A pH measurement? Or does a Batch A measurement inform a Batch B adjustment?

I'm not sure what you mean. I use the ph estimate on Beer Smith and then if I need to drop it I add a bit of lactic acid if I need to increase I add a bit of baking soda. It's not scientific but I've not had super off base ph. I learn from previous batches and adjust so i guess it's the "inform" side of your question!

 

[DanMalleck]

OP has chosen to move from fly sparging to batch sparging. A small hit to efficiency, yes, but simple, predictable, and repeatable.

dennybrew

Thanks. since I was fly sparging and had the efficiency problem, I switched to batch sparging. So I'm not sure going back to fly sparging will help much.

 

[DanMalleck]

Tighten the gap on your mill a little more. The end.

Thanks. My crush is quite fine. As noted in the post, I moisten the base grain to get more hulls so as to be able to handle a finer crush. Although there may be a problem in that my corona mill seems to be off centre and one side of the grinder produces a finer crush than the other. This is why I crush very fine.

 

[DanMalleck]

The biggest factor in efficiency is the quality of the crush. No other factor comes close. Mill finer until you get a stuck mash and your efficiency should rise, then open the mill just a little so you don't get a stuck mash next time. Better yet, replace that braid with a fine mesh bag and mill until you do get flour. With your grains contained in the bag you don't get a stuck mash because the bag forms a huge filter area. If the wort doesn't want to come out by itself you can force it by squeezing the bag.

The next factor in efficiency is how much wort you leave in the kettle at the end of the boil. If you do a whirlpool to leave the trub behind and get clear wort, much of what you leave behind is wort with suspended proteins. Dump it all into the fermenter and let the yeast decide what to leave behind. Give the beer sufficient time to settle out the proteins and a bunch of the yeast so you get clear beer into the bottles/keg.

Thanks. this answers another question which is "do you put the trub into the fermenter or stop when you're getting all the gunk?" I put it all in, running it through a sterilized fine mesh colander. I will keep making my crush finer

 

[DanMalleck]

In order to diagnose efficiency problems, the following data is needed:

• Grain bill details
• Strike water volume (actually all water added before end of mash)
• Sparge water volume
• Sparge process (fly, batch, or none, and if batch, how many sparge steps)
• SG of wort at end of mash, prior to run-off (should be after thorough stirring or thorough vorlauf)
• Pre-boil volume and SG (after thorough mixing of initial and sparge wort)
• Post-boil volume and SG (i.e. OG)
• Volume to fermenter

With this data it is possible to determine conversion efficiency (how well the mash worked), lauter efficiency (how well you separated sugar formed from the grain), mash efficiency (conversion efficiency * lauter efficiency), and brewhouse efficiency (which is less interesting than mash efficiency, since it is just mash efficiency * fermenter volume / post-boil volume.)

Conversion efficiency is primarily determined by crush fineness, mash time, and to a lesser extent by mash pH. Lauter efficiency is primarily determined by sparge process and grain absorption rate. Brewhouse is determined by the previous two, plus how much wort you leave behind going from BK to fermenter.

Measurement accuracy is critical, as the calculated efficiency can be no more accurate than the worst measurement that goes into the calculation. Volumes must be measured volumes, not target volumes, and should be measured to an accuracy of 0.1 gal (for a 5 gal batch.)

Without the above data, anything said about poor efficiency is just speculation.

Brew on

Thanks
I don't have all those numbers and some are in the OP. I'll try to put it in this form when I have a chance.

 

[RM-MN]

Thanks. My crush is quite fine. As noted in the post, I moisten the base grain to get more hulls so as to be able to handle a finer crush. Although there may be a problem in that my corona mill seems to be off centre and one side of the grinder produces a finer crush than the other. This is why I crush very fine.

Since I do BIAB and don't have the limitations of a conventional tun with the braid, I tighten my Corona until the plates rub when empty. That keeps them grinding the same on both sides. It also means that my mash efficiency is through the roof.

 

[DBhomebrew]

Thanks. since I was fly sparging and had the efficiency problem, I switched to batch sparging. So I'm not sure going back to fly sparging will help much.

A single batch sparge provides ~8% better efficiency than a full volume no sparge mash. A well-performed fly sparge may be equivalent to 3-4 batch sparges. The 1st batch sparge may gain 8%, but each subsequent one gains less and less. On a super big beer it might be worth a 2nd batch sparge to gain another 4% or so, but the 3rd & 4th are never going to gain you all that much.

TL;DR I think batch sparging's consistency more than makes up for its efficiency deficit to fly sparging.

 

[IslandLizard]

I have the feeling the tun doesn't get drained all the way.

On the inside of the tun, the bottom of the outlet (spigot) is at least 1/2" above the bottom. But you'll lose siphon when the top starts to suck air, another 1/2" higher.
Tilting the tun somewhat toward the spigot, at the end of lautering (draining) may help drain more completely.

Can you post a picture of the inside (bottom) of your tun? Braid and all.
Maybe also of the spigot/valve on the outside.
Do you clamp a hose on the outside of the drain?

[...] add the sparge water, stir for a bit, let it sit, then drain.

How about stirring a bit more aggressively? You really want all the grain bits rinsed out and everything in the mash thoroughly rinsed off.

Have you taken (and written down) gravity AND volume readings of each of your runnings?
IMO, that's key to how well the mash and lauter are working. I still do those, mostly out of habit, peace of mind, and also, just in case.
I write all collected data of a brew session on the Beersmith printout, and use the back too.

 

[mashpaddled]

I gave up on the toilet braid a few years ago after having the same kind of problems typically running low on preboil gravity and volume. I think the braid collapses and gets clogged which makes it difficult to drain effectively. When I would clean out the mash tun after brewing I always felt like I had a lot of runnings left behind. There's always deadspace in a mashtun but there shouldn't be half a gallon or more left behind. If you find a similar problem even with tipping the mash tun towards the valve, you found your problem.

I switched to a bazooka screen and completely resolved the problem. Not expensive and definitely worth the improved efficiency.

 

[DanMalleck]

I have the feeling the tun doesn't get drained all the way.

On the inside of the tun, the bottom of the outlet (spigot) is at least 1/2" above the bottom. But you'll lose siphon when the top starts to suck air, another 1/2" higher.
Tilting the tun somewhat toward the spigot, at the end of lautering (draining) may help drain more completely.

Can you post a picture of the inside (bottom) of your tun? Braid and all.
Maybe also of the spigot/valve on the outside.
Do you clamp a hose on the outside of the drain?


How about stirring a bit more aggressively? You really want all the grain bits rinsed out and everything in the mash thoroughly rinsed off.

Have you taken (and written down) gravity AND volume readings of each of your runnings?
IMO, that's key to how well the mash and lauter are working. I still do those, mostly out of habit, peace of mind, and also, just in case.
I write all collected data of a brew session on the Beersmith printout, and use the back too.

Haven't been that detailed with recording each of my runnings. I usually just record final volume into the kettle and take a reading of that.
Now I know why I should be more meticulous!

 

[DanMalleck]

Thanks to everyone for the questions and details. I may do another brew this week and will take more detailed readings.

 

[hotbeer]

Don't just take hydrometer readings alone. But each time note and record what the volume of wort or beer was at the time and how much water has been put into it up to that point.

 

[MicroMickey]

The biggest factor in efficiency is the quality of the crush. No other factor comes close. Mill finer until you get a stuck mash and your efficiency should rise, then open the mill just a little so you don't get a stuck mash next time. Better yet, replace that braid with a fine mesh bag and mill until you do get flour. With your grains contained in the bag you don't get a stuck mash because the bag forms a huge filter area. If the wort doesn't want to come out by itself you can force it by squeezing the bag.

The next factor in efficiency is how much wort you leave in the kettle at the end of the boil. If you do a whirlpool to leave the trub behind and get clear wort, much of what you leave behind is wort with suspended proteins. Dump it all into the fermenter and let the yeast decide what to leave behind. Give the beer sufficient time to settle out the proteins and a bunch of the yeast so you get clear beer into the bottles/keg.

My own experience forces me to disagree with that thought. A proper and thorough mash has much more to do with brewhouse efficiency than does the crush. The lauter and sparge is second in line for boosting gravity points.

 

[dmtaylor]

My own experience forces me to disagree with that thought. A proper and thorough mash has much more to do with brewhouse efficiency than does the crush. The lauter and sparge is second in line for boosting gravity points.

It's all important.

The crush is one of those things that might not seem like a problem... until it IS a problem.

I know for me, in my experience, when I dialed in my crush (this was almost 20 years ago), my efficiency suddenly jumped by about 10%. It definitely matters, and can matter a lot. Subsequent to that, with further adjustment I was averaging 92% brewhouse efficiency for a year or two... until I decided that was just odd, and I dialed it back, and have been happy at a more typical 82% average efficiency ever since.

YMMV

 

[hotbeer]

Brewhouse and mash efficiency don't directly equate to good or bad beer either. They just tell you whether your beer cost you more to make than the person that got a better efficiency.

 

[doug293cz]

Brewhouse and mash efficiency don't directly equate to good or bad beer either. They just tell you whether your beer cost you more to make than the person that got a better efficiency.

I think the only time low efficiency might be a functional problem is if you are trying to brew a high gravity beer on a volume limited system. For example, you might be able to make target gravity and volume at 70% efficiency, but not be able to at 50% efficiency. Otherwise, you only have to care if you are interested in getting the most out of things. I happen to find the math and mechanisms surrounding efficiency to be intellectually interesting. Understanding things can be its own goal.

Brew on

 

[pvtpublic]

Brewhouse and mash efficiency don't directly equate to good or bad beer either. They just tell you whether your beer cost you more to make than the person that got a better efficiency.

This is what you need to hear. Do the exact same beer the same way a few times so you can see where you are. If it varies, then you know that something is off with your process. If not, then just learn how to adjust your recipes to your efficiency. We can help with that, so can John Palmer with How to Brew, and Ray Daniels with Designing Great Beers.

 

[VikeMan]

A proper and thorough mash has much more to do with brewhouse efficiency than does the crush. The lauter and sparge is second in line for boosting gravity points.

The crush is one of those things that might not seem like a problem... until it IS a problem

The one thing that has the most to do with an efficiency problem is whatever thing happens to be the worst issue (constraint) in the particular equipment/process.

Based on decades of posts and resolutions, that is very often the crush. Perhaps the most often, just based on the fuzzy sum of my memories.

The strange thing is that (some) people sometimes want to offer advice about improving efficiency without gathering/considering any details about the equipment/process.