Maximizing Efficiency when Batch Sparging

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that'd be a good experiment! because i'm pretty sure if i threw into boiling water i'd get worse extraction then if i put in a warm bath....
 
Don't waste much of your home malt on that - maybe do a couple of comparative gallon batches :)

There have been the occasional posts where relative newcomers related profound efficiency hits - that turned out to be the use of uncrushed malt. There was one just a few weeks ago with some uncrushed wheat malt. Huge hit. So, I'm sticking with crush as #1 :)

Cheers!
 
I really don't mean to be contrary but . . . crush has a minor impact on mash efficiency unless you simply throw your malt in whole. Crushing malt to flour is not a good option either. I've known quite a few LHBS owners and none of them are so mercenary as to "rob" their customers by doing such an underhanded thing. Most customers might have a 60 to 70% extract efficiency but it isn't due to the crush. pH in the mash and sparge water is critical as is rinsing the sugars into the kettle. When you're done lautering, check the mash to see if you can find any sweetness remaining.

Most everything else FlyGuy wrote is just about there.
Mash efficiency is equal to conversion efficiency times lauter efficiency. Conversion efficiency is the percentage of convertible starches in the grain that actually got converted to sugar (and other dissolved material.) Lauter efficiency is the percentage of sugar that was created in the mash that actually made it into the BK. If you get 100% conversion efficiency, then mash efficiency equals lauter efficiency, otherwise mash efficiency is less than lauter efficiency.

The lauter efficiency obtainable with batch sparging is deterministic, and fairly easily calculated a priori. The only requirement for a good batch sparge is that you drain well before adding sparge water, you mix the sparge water aggressively with the grain, and then drain well again. A competent fly sparge will get better lauter efficiency than a batch sparge.

For a 12 lb grain bill with a weighted potential of 1.037, a typical MLT grain absorption rate of 0.12 gal/lb, zero undrainable MLT volume, 6.5 gal pre-boil volume, and equal run-off volumes for the initial mash and the sparge, the lauter efficiency is 84%. Many brewers have mash efficiencies in the 65% - 75% range. For that to be true with 84% lauter efficiency, the conversion efficiency has to be 76% - 88%. Smaller grain bills will have higher lauter efficiency, and larger grain bills will have lower lauter efficiency.

The most important variable for achieving high conversion efficiency is crush coarseness. Larger grits, from coarser crushes, take longer to gelatinize, and saccharification cannot occur until after gelatinization. Very fine crushes can complete saccharification in less than 20 minutes. Coarser crushes may not complete in 90 minutes. Mash pH plays a small role in the overall process, as it has little affect on gelatinization rate.

Net, if you are getting 60% - 70% mash efficiency, it is almost certainly because your conversion is nowhere near complete. Mashing longer can improve conversion efficiency, but the easiest way to get complete conversion is to crush fine.

Brew on :mug:
 
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The question of how to improve efficiency often comes up, and I sometimes get PMs asking advice. Rather than repeat the same information, I thought I would write my thoughts down in this thread so that it could be referenced in the future.

Efficiency issues are often difficult to diagnose -- it is just something you have to figure out through trial and error (for this reason, always take detailed notes of your recipe and process each and every brew!). Here are some ideas to think about, in approximate order of importance:

Your crush will have a big impact on your mash efficiency (although some debate this point). Regardless, the biggest gains in efficiency that users tend to report are when they improve their crush (e.g., buy their own mill). If your LHBS is crushing your grain for you, consider that most shops will set their crush so that their customers get between 60 and 70% efficiency. They may claim it is to help brewers avoid stuck mashes, but conveniently, it also helps them to sell more grain!

The ratio of sparge water to mash water is a critical factor determining efficiency when batch sparging. Some brewers forget that high gravity recipes will have proportionally less sparge water (because so much water was needed to mash the large volume of grain), and therefore, they will also have less water to dissolve extracted sugars resulting in lower extract efficiency. This seems to be particularly true for those who batch sparge. The two common solutions are either to add extra sparge water and lengthen the boil to compensate, or to simply plan for the reduction in efficiency in the recipe.

It is very important to hit your mash temperature and hold it for the length of the mash to get full conversion. A common problem is that people miss their temp (e.g., didnt pre-heat their mash tun or their thermometer is out of calibration), and their extract efficiency suffers because the enzymes in the mash were operating in less-than-optimal conditions.

Wort losses in the system (e.g., incomplete draining of mash tun or other dead spaces in gear like counter-flow chillers, etc.) can take a big toll on your brewhouse efficiency. These are sometimes overlooked because people are too focused on their extract efficiency rather than their overall (brewhouse) efficiency.

It is hard to accurately compute efficiency if you don't have precise measurements of your water/wort. Sometimes people think they are getting poor efficiency in their system, but it just turns out they are over-estimating the amount of water used in a brew or under-estimating the amount of wort collected.

When mixing your grain with water at the beginning of the mash, it is CRITICAL that everything is mixed completely to avoid doughballs or dry lumps of grain. If the grain is not sufficiently wetted, it won't convert, robbing you of efficiency points.

When batch sparging, the temperature of the mash-out and/or sparge water influence your extract efficiency. You want to make sure that either your mash-out infusion or your first batch sparge addition are hot enough to raise the grist to as close to 170 F as possible. This allows more sugar to be dissolved and reduces viscosity to facilitate easier lautering, both of which will improve your efficiency.

Also when batch sparging, it is critical that you stir the mash fully after adding mash-out water and/or the first sparge water addition. It may help to stir before each subsequent sparge water addition, but that depends on your system.

pH of the mash is usually not a problem for most brewers, but some water sources can be problematic. If so, the use of a pH stabilizer, like Five Star 5.2 buffer can help achieve an optimal mash pH, and may result in a 5 - 10% increase in efficiency.
Really the PH could increase the efficiency so much ? I should start adjusting the PH!
Thanks for the info FlyGuy!
 
Mash efficiency is equal to conversion efficiency times lauter efficiency. Conversion efficiency is the percentage of convertible starches in the grain that actually got converted to sugar (and other dissolved material.) Lauter efficiency is the percentage of sugar that was created in the mash that actually made it into the BK. If you get 100% conversion efficiency, then mash efficiency equals lauter efficiency, otherwise mash efficiency is less than lauter efficiency.

The lauter efficiency obtainable with batch sparging is deterministic, and fairly easily calculated a priori. The only requirement for a good batch sparge is that you drain well before adding sparge water, you mix the sparge water aggressively with the grain, and then drain well again. A competent fly sparge will get better lauter efficiency than a batch sparge.

For a 12 lb grain bill with a weighted potential of 1.037, a typical MLT grain absorption rate of 0.12 gal/lb, zero undrainable MLT volume, 6.5 gal pre-boil volume, and equal run-off volumes for the initial mash and the sparge, the lauter efficiency is 84%. Many brewers have mash efficiencies in the 65% - 75% range. For that to be true with 84% lauter efficiency, the conversion efficiency has to be 76% - 88%. Smaller grain bills will have higher lauter efficiency, and larger grain bills will have lower lauter efficiency.

The most important variable for achieving high conversion efficiency is crush coarseness. Larger grits, from coarser crushes, take longer to gelatinize, and saccharification cannot occur until after gelatinization. Very fine crushes can complete saccharification in less than 20 minutes. Coarser crushes may not complete in 90 minutes. Mash pH plays a small role in the overall process, as it has little affect on gelatinization rate.

Net, if you are getting 60% - 70% mash efficiency, it is almost certainly because your conversion is nowhere near complete. Mashing longer can improve conversion efficiency, but the easiest way to get complete conversion is to crush fine.

Brew on :mug:
Thank you i was wondering what’s the difference in the size of the crashed grains :cask:
 
The question of how to improve efficiency often comes up, and I sometimes get PMs asking advice. Rather than repeat the same information, I thought I would write my thoughts down in this thread so that it could be referenced in the future.

Efficiency issues are often difficult to diagnose -- it is just something you have to figure out through trial and error (for this reason, always take detailed notes of your recipe and process each and every brew!). Here are some ideas to think about, in approximate order of importance:

Your crush will have a big impact on your mash efficiency (although some debate this point). Regardless, the biggest gains in efficiency that users tend to report are when they improve their crush (e.g., buy their own mill). If your LHBS is crushing your grain for you, consider that most shops will set their crush so that their customers get between 60 and 70% efficiency. They may claim it is to help brewers avoid stuck mashes, but conveniently, it also helps them to sell more grain!

The ratio of sparge water to mash water is a critical factor determining efficiency when batch sparging. Some brewers forget that high gravity recipes will have proportionally less sparge water (because so much water was needed to mash the large volume of grain), and therefore, they will also have less water to dissolve extracted sugars resulting in lower extract efficiency. This seems to be particularly true for those who batch sparge. The two common solutions are either to add extra sparge water and lengthen the boil to compensate, or to simply plan for the reduction in efficiency in the recipe.

It is very important to hit your mash temperature and hold it for the length of the mash to get full conversion. A common problem is that people miss their temp (e.g., didnt pre-heat their mash tun or their thermometer is out of calibration), and their extract efficiency suffers because the enzymes in the mash were operating in less-than-optimal conditions.

Wort losses in the system (e.g., incomplete draining of mash tun or other dead spaces in gear like counter-flow chillers, etc.) can take a big toll on your brewhouse efficiency. These are sometimes overlooked because people are too focused on their extract efficiency rather than their overall (brewhouse) efficiency.

It is hard to accurately compute efficiency if you don't have precise measurements of your water/wort. Sometimes people think they are getting poor efficiency in their system, but it just turns out they are over-estimating the amount of water used in a brew or under-estimating the amount of wort collected.

When mixing your grain with water at the beginning of the mash, it is CRITICAL that everything is mixed completely to avoid doughballs or dry lumps of grain. If the grain is not sufficiently wetted, it won't convert, robbing you of efficiency points.

When batch sparging, the temperature of the mash-out and/or sparge water influence your extract efficiency. You want to make sure that either your mash-out infusion or your first batch sparge addition are hot enough to raise the grist to as close to 170 F as possible. This allows more sugar to be dissolved and reduces viscosity to facilitate easier lautering, both of which will improve your efficiency.

Also when batch sparging, it is critical that you stir the mash fully after adding mash-out water and/or the first sparge water addition. It may help to stir before each subsequent sparge water addition, but that depends on your system.

pH of the mash is usually not a problem for most brewers, but some water sources can be problematic. If so, the use of a pH stabilizer, like Five Star 5.2 buffer can help achieve an optimal mash pH, and may result in a 5 - 10% increase in efficiency.
Fantastic advice, looking forward to using on my next batch!
 
Really old thread, but still very relevant. I can also confirm grain crush size has huge impact. I have always asked my local home brew shop to crush the grain for me, but always thought it was poorly crushed. Anyhow, I got a grain crush a few days ago and used it for the first time today. Checked my last 10 batches and they all had a mash efficiency of between 70-80%. Today I crushed 0.025" / 0.64 mm and got a mash efficiency of 94%!
I've played around with PH stabilizer back and forth as well and have actually never noted down in which batches I've used it in, nor experienced any big difference. Worth mentioning is that I used it today though, which of course could have had an impact. Also, due to the finer crush, I was afraid to have a stuck mash and agitated it every 10 minutes or so.

Expected OG was 1.048 based on 75% mash efficiency, but I got 1.062. I'm really looking forward to brewing cheaper beer going forward :)
 
Mash efficiency will help and I average 90% for this, but downstream of this boil and trub losses effect your batch volume. Assume you hit your target volume or did you liquor back to get a bigger volume.
 
Mash efficiency will help and I average 90% for this, but downstream of this boil and trub losses effect your batch volume. Assume you hit your target volume or did you liquor back to get a bigger volume.
Normally I sparge after mash, but today I mashed full volume and used a lid from one of my sauce pans to press out any liquid I could from the grain basket. Batch volume got up from expected 12 liters to 14 liters and brewhouse efficiency got up from around 60% (recent batches) to 77%.
 
Thanks, a good bhe improvement.
A small space of a couple of litres and you might find you have wort for a free starter. I just put this in a pot bottle and freeze it. Then defrost and use in my normal starter protocol.
Checking the sparge gravity also might show a further batch gain potential.
 
Really old thread, but still very relevant. I can also confirm grain crush size has huge impact. I have always asked my local home brew shop to crush the grain for me, but always thought it was poorly crushed. Anyhow, I got a grain crush a few days ago and used it for the first time today. Checked my last 10 batches and they all had a mash efficiency of between 70-80%. Today I crushed 0.025" / 0.64 mm and got a mash efficiency of 94%!
I've played around with PH stabilizer back and forth as well and have actually never noted down in which batches I've used it in, nor experienced any big difference. Worth mentioning is that I used it today though, which of course could have had an impact. Also, due to the finer crush, I was afraid to have a stuck mash and agitated it every 10 minutes or so.

Expected OG was 1.048 based on 75% mash efficiency, but I got 1.062. I'm really looking forward to brewing cheaper beer going forward :)

Normally I sparge after mash, but today I mashed full volume and used a lid from one of my sauce pans to press out any liquid I could from the grain basket. Batch volume got up from expected 12 liters to 14 liters and brewhouse efficiency got up from around 60% (recent batches) to 77%.
Congratulations on getting your own mill. This is often the cause of a significant improvement in a brewer's efficiency.

Getting 94% lauter efficiency with a full volume (no sparge) mash is almost impossible (unless you have an industrial filter press.) And, since mash efficiency = conversion efficiency * lauter efficiency, mash efficiency must be less than or equal to lauter efficiency. I suspect there are significant measurement errors affecting your mash efficiency calculations.

Crush has very little to no effect on lauter efficiency, but often has a large effect on conversion efficiency, and thus mash efficiency. Larger grits (grain bits) convert more slowly than smaller grits, so often times are not completely converted during the allotted mash time, making conversion efficiency less than 100%, and thus lowering mash efficiency.

Brew on :mug:
 
Congratulations on getting your own mill. This is often the cause of a significant improvement in a brewer's efficiency.

Getting 94% lauter efficiency with a full volume (no sparge) mash is almost impossible (unless you have an industrial filter press.) And, since mash efficiency = conversion efficiency * lauter efficiency, mash efficiency must be less than or equal to lauter efficiency. I suspect there are significant measurement errors affecting your mash efficiency calculations.

Crush has very little to no effect on lauter efficiency, but often has a large effect on conversion efficiency, and thus mash efficiency. Larger grits (grain bits) convert more slowly than smaller grits, so often times are not completely converted during the allotted mash time, making conversion efficiency less than 100%, and thus lowering mash efficiency.

Brew on :mug:
Thanks, I also hope and believe it will increase my efficiency.

The calculation is from Brewfather, so I don't think that should be an issue. I could of course have messed up when I measured pre boil gravity, but I did it the same way I always do (let it cool down to room temp before measuring), so even if it's erroneous it's still a huge improvement from earlier batches. I have been thinking about getting a refractometer instead of the hydrometer I've used for the last couple of years though. That might get more accurate readings.
 
Thanks, I also hope and believe it will increase my efficiency.

The calculation is from Brewfather, so I don't think that should be an issue. I could of course have messed up when I measured pre boil gravity, but I did it the same way I always do (let it cool down to room temp before measuring), so even if it's erroneous it's still a huge improvement from earlier batches. I have been thinking about getting a refractometer instead of the hydrometer I've used for the last couple of years though. That might get more accurate readings.
I am quite certain that you did achieve a significant improvement in efficiency.

The largest inaccuracies in efficiency calculations often come from volume measurement errors. Inadequate homogenization of wort prior to taking pre-boil samples can also lead to significant errors in SG values, but this is usually only a problem for sparged processes. Errors can also come from grain weight measurement errors, inaccurate grain potential values, and failure to correct for the moisture content of the grain by many calculation tools (I don't know if this last one applies to Brewfather or not, but I know it applies to some others.) The calculations can be no more accurate than the data that is input to them.

Brew on :mug:
 
I've played around with PH stabilizer back and forth as well and have actually never noted down in which batches I've used it in, nor experienced any big difference.

If by "PH Stabilizer" you are referring to the Five Star product, I don't think I've ever read of it working...for anyone. Which makes sense - it was designed for one specific commercial customer's water, so unless your water matches that one customer's water it's unlikely to do much good for you...

Cheers!
 
If by "PH Stabilizer" you are referring to the Five Star product, I don't think I've ever read of it working...for anyone. Which makes sense - it was designed for one specific commercial customer's water, so unless your water matches that one customer's water it's unlikely to do much good for you...

Cheers!
That's the one, yes. Never noticed any difference here either. But figured I might as well use what's left. I assume it wont hurt even if it wont help.
 
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