Brewhouse Efficiency

[tomwhit19]

Brewed a cream ale yesterday (12/10) and had a few firsts, but not necessarily bad firsts, it was the first time attempting to fly sparge (just used a strainer to pour sparge water through), was also the first time using a propane burner instead of the stove top and this is where lies my question/curiosity/minor slight concern

The brew day started off great, the propane burner kicks ass and heated our strike water to where we were aiming for (168 to have a mash temp of 153) in about 15 -20 mins, which never happens that fast on the stove top, after the mash of 1 hour we collect our wort (6.5 gal) and fired up the burner again. on the stove top over a 1 hour boil our boil off rate has always been about .5 gal, on the propane burner we ended up with a 1.5 gal boil off which obviously gave us 1 gal less than we were aiming for going into the primary.

Thats the back story to my question which is, since we had such a high boil off % is that why our brewhouse efficiency came out to 56%????

 

[CJ-3]

Can you post up the recipe you used and the mash schedule? It will help a lot with troubleshooting.

 

[Smellyglove]

Brewhouse efficiency is more about how much wort you leave behind in the different stages. It's about losses. If you have x amount of gravitypoints in a given amount of wort, and compare it to the double amount of points in half amount of volume, you still end up with the same amount of total gravitypoints. Unless your post mash efficiency is pretty off then don't worry about it.


You need to start looking at your mash efficiency.
When recipes call for brewhouse efficiency I feel that that number is worth 0, since you don't know how much is left behind in various stages at that brewhouse. To nail a recipe grist-wise you just need to know grist composition in % and OG, with those two numbers you can adapt it to your setup. But you need to know your setup.

 

[MandingaBIAB]

BIAB gives me such high efficiency I've never seen a reason to bother with things such as sparging. I encourage you to give this method a try as it is the future of brewing on all scales.

 

[tomwhit19]

I feel like we were damn close in our mash efficiency our est og was 1.048 we hit 1.044 and our est preboil vol was 6.5 gal and i rounded up in the op but we were a shade under the 6.5 gal line id say 6.45 but in the picture i posted (NOT MY NUMBERS JUST A SAMPLE, mine are on another computer) in the circled area our Meas Efficiency was 55.9% is that an overall of the whole process?

Also a couple other questions from that image what are the differences between End of Runnings Gravity, Post Mash Gravity, and Pre Boil Gravity? Wouldnt they essentially all be the same thing?

 

[Francus]

I agree with Smellyglove (above), brewhouse efficiency is not worth a whole lot, especially for a home brewer. For the big boys it can mean a big difference to the bottom line. The mash efficiency is your best gauge of where you are. You said you got 55.9%. I would say that is low, even for a propane system. Your mash efficiency comes from you're pre-boil gravity and volume of wort. I can't tell if the 1.044 SG you got was pre-boil or OG. If it was OG then your pre-boil was much lower, maybe 1.035 ish. For a propane system where you have fine tuned the process I would speculate you should be getting at least mid 60s percent wise. Maybe even high 60's.

I have no experience with BIAB, so I can't say much about efficiencies. After years (decades) of brewing on propane I went to electric and I usually have mash efficiencies in the low 90s.

As for the other items:

• End of Runnings Gravity: This is the gravity of the wort coming off your sparge. You will notice at the beginning of your sparge the specific gravity is much higher. The generally recommended practice is to stop sparging (collecting runoff) when the SG of the wort hits 1.010. Going too much lower will add a bitterness to the beer. In reality, for a paler beer I would stop collecting sparge runoff at 1.012 and for a dark beer like a stout you can go down to 1.006 with no adverse affect. Or just do 1.010 and call it a day.
• Post Mash Gravity: This is the SG of the gravity in the boil kettle before any additional sugars are added. This is the same as Pre Boil Gravity if no additional sugars are added. Some situations where additional sugars are added are for Belgian Strong ales or lactose for a Milk Stout. Remember to stir in the boil kettle as the denser runoff will more or less be at the bottom. So give it a good stir then take a reading.
• Pre Boil Gravity: As mentioned before, this is most often the same as Post Mash Gravity unless your recipe called for sugars to be added in the boil kettle. The reason you want to take the Pre-Boil Gravity as well if you add sugars is because the SG will affect hop isomerization and thus your brew's bitterness.

 

[FunkedOut]

I’m a bit confused.
In the OP, you say you were a gallon short of 6.5 gallons.
I’m your last post, you say you were short 0.05 gallons.
You also say in your last post you were 4 gravity points shy of your OG.
Please explain.

What does the equipment profile you were using have in it for brewhouse efficiency?

Background info:

Mash efficiency is about how much of the theoretical maximum sugars in the grain are extracted into the wort.

Brewhouse efficiency is about how much of the theoretical maximum sugars in the grain make it into the fermenter.
Any wort (sugars) left in the kettle, chiller, pump, hoses hurts this number.

I lost 10% in BH efficiency when I added a pump, 10’ of 1/2” hose and a drain valve that leaves a quart of wort in the kettle. Mash efficiency didn’t change at all.

If you were to pour all of the contents of the boil kettle into the fermenter, boil off would have zero impact to your BH efficiency.

 

[tomwhit19]

I agree with Smellyglove (above), brewhouse efficiency is not worth a whole lot, especially for a home brewer. For the big boys it can mean a big difference to the bottom line. The mash efficiency is your best gauge of where you are. You said you got 55.9%. I would say that is low, even for a propane system. Your mash efficiency comes from you're pre-boil gravity and volume of wort. I can't tell if the 1.044 SG you got was pre-boil or OG. If it was OG then your pre-boil was much lower, maybe 1.035 ish. For a propane system where you have fine tuned the process I would speculate you should be getting at least mid 60s percent wise. Maybe even high 60's.

I have no experience with BIAB, so I can't say much about efficiencies. After years (decades) of brewing on propane I went to electric and I usually have mash efficiencies in the low 90s.

As for the other items:

• End of Runnings Gravity: This is the gravity of the wort coming off your sparge. You will notice at the beginning of your sparge the specific gravity is much higher. The generally recommended practice is to stop sparging (collecting runoff) when the SG of the wort hits 1.010. Going too much lower will add a bitterness to the beer. In reality, for a paler beer I would stop collecting sparge runoff at 1.012 and for a dark beer like a stout you can go down to 1.006 with no adverse affect. Or just do 1.010 and call it a day.
• Post Mash Gravity: This is the SG of the gravity in the boil kettle before any additional sugars are added. This is the same as Pre Boil Gravity if no additional sugars are added. Some situations where additional sugars are added are for Belgian Strong ales or lactose for a Milk Stout. Remember to stir in the boil kettle as the denser runoff will more or less be at the bottom. So give it a good stir then take a reading.
• Pre Boil Gravity: As mentioned before, this is most often the same as Post Mash Gravity unless your recipe called for sugars to be added in the boil kettle. The reason you want to take the Pre-Boil Gravity as well if you add sugars is because the SG will affect hop isomerization and thus your brew's bitterness.

We did take a pre boil gravity which came out around 1.032 if I remember correctly, I wrote all our readings and temps down then our pre boil volume was 6.45 gal roughly with no water top up and our OG was 1.044 but we had 1.5 ga boil off so I’m assuming the 1.5 ga boil off is affecting that 55.9% efficiency? Unless that is a calculation of total efficiency and not mash efficiency which is what my question is because I entered all the numbers on brewersfriend and it came up that mash efficiency was 68% which seems a lot better and closer to what we normally get but the 55.9% that BS is kicking back is what’s throwing me off

 

[n3lson1]

Was the burner cranking the whole time? Usually you judt want to crank the burner until you are boiling then turn down a bit you want a nice strong boil but not mega vigorous. The more vigorous the boil the more loss you will have.

 

[FatDragon]

Boiloff won't affect your efficiency because it boils off water, not sugars. The reduction in volume brings a corresponding increase in gravity. Efficiency doesn't measure how much beer you get, but how much sugar you get out of the grain and into the beer. 5 gallons at 1.050 is the same efficiency as 2.5 gallons at 1.100.

 

[doug293cz]

Amount of boil off has zero effect on efficiency. You have the same amount of sugar in the kettle at the end of boil as you did at the beginning (unless you added sugar during the boil, or lost wort to spillage/boil-over.) As said previously, efficiency is all about the amount of sugar you got vs. the max possible. Efficiency goes down when you leave sugar behind. Sounds like you had low mash efficiency, which then has to carry forward to low BH efficiency. If your mash efficiency was 68% and BH was 56%, that means you lost 1 - (56 / 68) = 0.176 or 17.6% of your wort going from your BK (post-boil) to your fermenter. Your BK to fermenter transfer efficiency was only 82 - 83%.

Without knowing your grain bill weight, post-boil SG and post-boil volume (in the BK), we can't cross check your mash efficiency number.

Attached is a primer I put together on efficiency.

Brew on

 

[Sadu]

Amount of boil off has zero effect on efficiency. You have the same amount of sugar in the kettle at the end of boil as you did at the beginning

This isn't entirely correct. More boiloff means you have more sparge water to work with which usually means better brew house efficiency.
This doesn't explain getting 55% though, something else is going on.

 

[doug293cz]

This isn't entirely correct. More boiloff means you have more sparge water to work with which usually means better brew house efficiency.
This doesn't explain getting 55% though, something else is going on.

That's more properly accounted for as differences in pre-boil volume for the same grain weight. Once your pre-boil volume is determined, then the amount you boil-off does not affect efficiency. You can improve your efficiency a bit by planning a higher boil-off to allow an increase in pre-boil volume, which allows you to use more brewing water. Check out the chart on the last page of the .pdf attached to my previous post.

 

[balrog]

pre boil gravity 1.032 pre boil vol 6.45 gal OG 1.044 1.5 ga boil off ... brewersfriend ... mash efficiency 68%

I used to get confused when diff places used diff adjectives in front of "efficiency" (mash, lauter, brew house, total, lunar, ecclesiastical, etc).

I look at it this way -- there's no way to know without knowing your grain bill to calc theoretically how many points you should get (@doug293cz 's paper is a good read, Kaiser's wiki will blow your mind). But if you got 1.032 with 6.5 and boiled to 5.0, (32 * 6.5/5 =~ 42) then that seems to be reasonable with your measured OG 1.044.

The main thing would be whether your process repeats. This fact alone allows you to know what to plan for grain bill in the future. Otherwise you're back to casting chicken bones.

 

[RM-MN]

There are two major factors that affect your brewhouse efficiency. First it the crush of the grain. If the water can't get to the starch to gelatinize it, the enzymes can't convert the starch to sugar and you leave a lot of potential sugar in the grain you dump out. The second is in the recovery of the sugar you did get converted. Done just right, a fly sparge can collect more sugars than a batch sparge (not much more than a double batch sparge but still more). Done badly, a fly sparge can be a disaster. If your sparge water creates a channel that it can flow through instead of slowly seeping through the grain it leaves most of the sugar behind in the grain, which you then dump out.

Forget that fly sparge for the moment. Knowing that the double batch sparge will be close to the same, do that instead on your next batches. If your brewhouse efficiency comes up, you know the cause. If it doesn't come up, you can blame the crush of the grain and are well on your way to fixing that problem.

 

[tomwhit19]

I used to get confused when diff places used diff adjectives in front of "efficiency" (mash, lauter, brew house, total, lunar, ecclesiastical, etc).

I look at it this way -- there's no way to know without knowing your grain bill to calc theoretically how many points you should get (@doug293cz 's paper is a good read, Kaiser's wiki will blow your mind). But if you got 1.032 with 6.5 and boiled to 5.0, (32 * 6.5/5 =~ 42) then that seems to be reasonable with your measured OG 1.044.

The main thing would be whether your process repeats. This fact alone allows you to know what to plan for grain bill in the future. Otherwise you're back to casting chicken bones.

Grain Bill is as follows

Cream Ale
4# 6 row
3# 2 row
1.5# flakes corn
1# carapils/dextrine
.5# caramel30

Post mash gravity 1.032
6.45 gal collected from mash with fly sparge
OG 1.044
4.5 gal into primary....roughly 1/4 gal left behind to trub hop debris

 

[tomwhit19]

There are two major factors that affect your brewhouse efficiency. First it the crush of the grain. If the water can't get to the starch to gelatinize it, the enzymes can't convert the starch to sugar and you leave a lot of potential sugar in the grain you dump out. The second is in the recovery of the sugar you did get converted. Done just right, a fly sparge can collect more sugars than a batch sparge (not much more than a double batch sparge but still more). Done badly, a fly sparge can be a disaster. If your sparge water creates a channel that it can flow through instead of slowly seeping through the grain it leaves most of the sugar behind in the grain, which you then dump out.

Forget that fly sparge for the moment. Knowing that the double batch sparge will be close to the same, do that instead on your next batches. If your brewhouse efficiency comes up, you know the cause. If it doesn't come up, you can blame the crush of the grain and are well on your way to fixing that problem.

Thanks for the info, we always used a single batch sparge but decided to give the fly sparge a try this time around

 

[RM-MN]

Grain Bill is as follows

Cream Ale
4# 6 row
3# 2 row
1.5# flakes corn
1# carapils/dextrine
.5# caramel30

Post mash gravity 1.032
6.45 gal collected from mash with fly sparge
OG 1.044
4.5 gal into primary....roughly 1/4 gal left behind to trub hop debris

This probably isn't the major problem but it doesn't help the situation. Dump it all into the fermenter. When the beer is done it will have settled out and be easy to siphon from above it, getting nearly all the beer.

 

[doug293cz]

Grain Bill is as follows

Cream Ale
4# 6 row
3# 2 row
1.5# flakes corn
1# carapils/dextrine
.5# caramel30

Post mash gravity 1.032
6.45 gal collected from mash with fly sparge
OG 1.044
4.5 gal into primary....roughly 1/4 gal left behind to trub hop debris

With ~100% conversion efficiency, and a "good" fly spage, you should have hit a pre-boil SG of around 1.050 - 1.052, and a post-boil OG of around 1.066 - 1.068. Now assuming your fly sparge was good, that implies your conversion efficiency would have to be around 65 - 66%, which is pretty dismal. If we assume your sparge was bad (no better than a no sparge process), then your conversion efficiency could have been as high as 77%, still not good. So, at the minimum you have low conversion efficiency (you're not converting all the starch to sugar.) Conversion efficiency should be above 90%, 95% is pretty good, but 98 - 100% is achievable with a fine crush.

Brew on

 

[tomwhit19]

okay thanks everyone, a lot of info here, a lot of trying to understand here, i just want to recap here quick. so brewhouse efficiency-not so important for smaller batches

main focuses are mash efficiency and lauter efficiency

~someone correct me if im wrong~
mash efficiency - how much of the available sugars is extracted from the grain in the mash
lauter efficiency - how much of the available sugars makes it to the boil kettle

assuming the above is correct for all grain no BIAB what is are good mash and lauter efficincies? and how does one increase these efficiencies if they are on the lower side? trying to grasp all this with all the info being thrown around on this, feel like i had it in my head then it was gone

 

[doug293cz]

okay thanks everyone, a lot of info here, a lot of trying to understand here, i just want to recap here quick. so brewhouse efficiency-not so important for smaller batches

main focuses are mash efficiency and lauter efficiency

~someone correct me if im wrong~
mash efficiency - how much of the available sugars is extracted from the grain in the mash
lauter efficiency - how much of the available sugars makes it to the boil kettle

assuming the above is correct for all grain no BIAB what is are good mash and lauter efficincies? and how does one increase these efficiencies if they are on the lower side? trying to grasp all this with all the info being thrown around on this, feel like i had it in my head then it was gone

Your "mash efficiency" is actually conversion efficiency. Mash efficiency is the percentage of the grains' potential sugar that makes it into the BK. Mash efficiency is equal to conversion efficiency times lauter efficiency. Good conversion efficiency is 95 - 100%. Lauter efficiency depends on the ratio of grain weight (lbs) to pre-boil volume (gal). The higher the ratio, the lower the lauter efficiency. Lauter efficiency also depends on the number of sparge steps for batch sparging. For fly sparging, the best you can do is 2 - 3 percentage points better than a triple batch sparge.

It's relatively easy to get the max possible lauter efficiency when batch sparging (just need to stir well before each run off, and keep all the run offs relatively equal volumes.)

Getting a good fly sparge is not so simple. You need to use a slow enough flow rate that sugar absorbed in the grain can diffuse into the spage wort faster than the sparge wort flows by, and you must have uniform flow of the sparge wort across the whole grain bed (ie no channeling.)

The last page of the .pdf I attached above shows what you can expect for batch sparge (including no sparge) lauter efficiency as a function of grain bill size and number of sparge steps. A typical MLT grain absorption is about 0.12 gal/lb (the solid lines on the chart.)

With 100% conversion efficiency, your mash efficiency will equal your lauter efficiency. At lower conversion efficiencies, your mash efficiency will be lower than your lauter efficiency.

Brew on

 

[tomwhit19]

Your "mash efficiency" is actually conversion efficiency. Mash efficiency is the percentage of the grains' potential sugar that makes it into the BK. Mash efficiency is equal to conversion efficiency times lauter efficiency. Good conversion efficiency is 95 - 100%. Lauter efficiency depends on the ratio of grain weight (lbs) to pre-boil volume (gal). The higher the ratio, the lower the lauter efficiency. Lauter efficiency also depends on the number of sparge steps for batch sparging. For fly sparging, the best you can do is 2 - 3 percentage points better than a triple batch sparge.

It's relatively easy to get the max possible lauter efficiency when batch sparging (just need to stir well before each run off, and keep all the run offs relatively equal volumes.)

Getting a good fly sparge is not so simple. You need to use a slow enough flow rate that sugar absorbed in the grain can diffuse into the spage wort faster than the sparge wort flows by, and you must have uniform flow of the sparge wort across the whole grain bed (ie no channeling.)

The last page of the .pdf I attached above shows what you can expect for batch sparge (including no sparge) lauter efficiency as a function of grain bill size and number of sparge steps. A typical MLT grain absorption is about 0.12 gal/lb (the solid lines on the chart.)

With 100% conversion efficiency, your mash efficiency will equal your lauter efficiency. At lower conversion efficiencies, your mash efficiency will be lower than your lauter efficiency.

Brew on

So what are ways to increase conversion efficiency?

And what i highlighted in the quote if im understanding this correctly its saying that if the grain bill weight is 7# than preboil volume would have to be 7 gal for 100% lauter efficiency?

I'm stuggling a bit with this and its probably a lot simpler than im making it out to be

 

[FatDragon]

So what are ways to increase conversion efficiency?

And what i highlighted in the quote if im understanding this correctly its saying that if the grain bill weight is 7# than preboil volume would have to be 7 gal for 100% lauter efficiency?

I'm stuggling a bit with this and its probably a lot simpler than im making it out to be

Calculating lauter efficiency depends on knowing the grain weight and pre-boil volume.

Conversion efficiency is how much of the starches are converted to sugars. Good grind, proper mash temperature, a long-enough mash, and maybe other things like pH are involved in conversion efficiency.

Lauter efficiency is how much converted sugar you get out of the grain and into the kettle. The point of a sparge is to rinse sugar out of the grain and into the kettle. The more sugar in the kettle, the higher your lauter efficiency. I believe it's calculated as a percentage of the potential gravity from your grainbill (EDIT: this is wrong - that's Mash Efficiency), so if your grain has enough potential to make 5 gallons of wort at 1.050 at 100% efficiency and you get 1.025, you achieved 50% lauter efficiency. Note that recipes are typically designed for roughly 70-80% lauter efficiency, so a recipe designed for five gallons at 1.050 generally has enough grain to hit 1.060+ if you somehow achieved 100% efficiency, so if you're brewing someone else's recipe, don't use their intended gravity as your baseline for 100% lauter efficiency.

 

[doug293cz]

So what are ways to increase conversion efficiency?

And what i highlighted in the quote if im understanding this correctly its saying that if the grain bill weight is 7# than preboil volume would have to be 7 gal for 100% lauter efficiency?

I'm stuggling a bit with this and its probably a lot simpler than im making it out to be

No, you can never get 100% lauter efficiency, since you cannot get all of the wort out of the spent grain. The wort left in the spent grain contains some of the sugar you created in the mash. Look at the chart on the last page of the .pdf - lauter efficiency never gets to 100%.

Sparging rinses sugar out of the spent grain, and dilutes the wort left in the spent grain. For the same amount of wort absorbed by the grain, the more dilute that wort, the better the efficiency.

You increase lauter efficiency by doing more sparges (fly sparging can be thought of as doing a very large number of very small sparges, one right after the other), and/or reducing the amount of wort retained by the grain (i.e. squeezing.) Each additional sparge step provides less efficiency improvement than the previous sparge step, so you get diminishing returns for each increment of additional work.

Brew on

 

[doug293cz]

Calculating lauter efficiency depends on knowing the grain weight and pre-boil volume.

Conversion efficiency is how much of the starches are converted to sugars. Good grind, proper mash temperature, a long-enough mash, and maybe other things like pH are involved in conversion efficiency.

Lauter efficiency is how much converted sugar you get out of the grain and into the kettle. The point of a sparge is to rinse sugar out of the grain and into the kettle. The more sugar in the kettle, the higher your lauter efficiency. I believe it's calculated as a percentage of the potential gravity from your grainbill, ...

No, lauter efficiency isn't really affected by the potential of the grain bill. Lauter efficiency is defined as:

Lauter Efficiency = Amount of Extract in BK / Amount of Extract Created in Mash​

It's a measure of how well you recovered the created extract (extract is everything dissolved in the wort, about 90% sugar). Conversion efficiency measures how well you converted potential extract to actual extract. Together conversion efficiency and lauter efficiency give you mash efficiency.

Brew on

 

[FatDragon]

No, lauter efficiency isn't really affected by the potential of the grain bill. Lauter efficiency is defined as:

Lauter Efficiency = Amount of Extract in BK / Amount of Extract Created in Mash​

It's a measure of how well you recovered the created extract (extract is everything dissolved in the wort, about 90% sugar). Conversion efficiency measures how well you converted potential extract to actual extract. Together conversion efficiency and lauter efficiency give you mash efficiency.

Brew on

Got it, so my definition of lauter efficiency was actually mash efficiency, then? This is why I should stay out of discussions of efficiency - there are too many efficiency values and I get them mixed up all the time...

How does one measure conversion efficiency (or lauter efficiency, for that matter)? Kettle gravity at any point in the process will be variably affected by both of these values, so you can't measure conversion efficiency in the kettle and you can't measure lauter efficiency without knowing your conversion efficiency. Do first runnings give an accurate reflection of conversion efficiency?

Anyway, I'll stick with mash efficiency in my own brewing. It's easy to measure and provides enough information for my purposes (when I bother checking it at all). Heck, I haven't even checked OG (much less pre-boil gravity) on about half of my recent brews...

 

[MaryB]

I measure brew house efficiency on the wort that goes to the fermenters. If I drop under 80% I know I have a problem of some sort(last time was a thermometer that lost calibration and dropped me to 75% from to cold of a mash.) I average 82% efficiency the way I measure it.

One thing to remember, take the temp of your sample and make sure you offset the reading of your hydrometer using one of the calculators. Hotter sample means lower reading.

 

[doug293cz]

Got it, so my definition of lauter efficiency was actually mash efficiency, then? Yes This is why I should stay out of discussions of efficiency - there are too many efficiency values and I get them mixed up all the time... The terminology is not consistent across the brewing community. I like to push the terminology used by BeerSmith and BrewersFriend since those are among the most common places homebrewers go to do efficiency calculations.

How does one measure conversion efficiency (or lauter efficiency, for that matter)? Kettle gravity at any point in the process will be variably affected by both of these values, so you can't measure conversion efficiency in the kettle and you can't measure lauter efficiency without knowing your conversion efficiency. Do first runnings give an accurate reflection of conversion efficiency?

Anyway, I'll stick with mash efficiency in my own brewing. It's easy to measure and provides enough information for my purposes (when I bother checking it at all). Heck, I haven't even checked OG (much less pre-boil gravity) on about half of my recent brews...

Conversion efficiency is measured by measuring the SG of the wort in the mash after homogenization (should be same as first runnings gravity.) Turns out that max mash SG is pretty much just a function of the mash thickness (strike water to grain weight ratio.) The method for measuring conversion efficiency is given here: http://braukaiser.com/wiki/index.php?title=Understanding_Efficiency#Measuring_conversion_efficiency.

Lauter efficiency is then calculated as:

Lauter Efficiency = Mash Efficiency / Conversion Efficiency.​

For recipe calculations, mash efficiency is sufficient. If you are trying to diagnose low mash efficiency, it helps to know if your conversion efficiency, lauter efficiency, or both are lower than they should be.

Brew on