Which efficiency number is most important?

[Echo2112]

I am using Beer Smith, and when I go to the efficiency details screen, it lists the efficiency based on target volume, into boiler and into fermenter.

So which number is the one that is most important to consider? I just did my first all grain batch, it went smooth, no issues, but I didn't know which number is the efficiency that all grain brewers look for.

The into boiler number was 80.12%

The number for into fermenter was 66.54%

And the number for Target volume was 64.02%.

That last one is low, but I am pretty sure I know why. I have added honey to the fermenter, but it was not included in the boil, so when I took my reading it was from the kettle, and the honey was not there. When I remove the honey from the ingredient list it takes it up to 84%.

So which number is the one I see thrown around the most?

 

[Baja_Brewer]

I dont use BeerSmith that much yet, but this really spelled it out for me. I know thats not a direct response, but doing it out by hand a few times really gives you a good understanding of it.

 

[GilaMinumBeer]

Both are equally important sequentially.

The first is important in that it calcs how well your conversion and sparge went in respect to hitting your target gravity and volume (pre-boil) into the boiler. Any drastic deviations here indicates you are (one or more of the following); using more grain than needed, aren't sparging adequately, aren't getting a good conversion, over sparging, need to adjust hop rates, etc...

The second indicates how well you accounted for boil-off to hit your target volume and then for system losses, trub loss, etc... to hit your desired volume into the fermenter. Again drastic deviations may indicate problems with gravity and hop rates.

 

[remilard]

Into boiler is the one that is important for predicting pre-boil gravity. That and boil off rate are important for predicting post boil gravity.

How much you leave in the boil kettle (and maybe hoses and pump heads) is a function of what kind and how many hops you use, how and if you strain or divert or leave behind wort in the kettle. That is unimportant to me.

 

[Echo2112]

I dont use BeerSmith that much yet, but this really spelled it out for me. I know thats not a direct response, but doing it out by hand a few times really gives you a good understanding of it.

It is good info, I even went over it in the book, I guess i just never worked through the math there. Guess I can't complain then, if 30 is the number a lot of people shoot for, my math gave me 36.37.

Course working through the rest of the math for the Maximum PPG on 2 row pale malt means that if I am doing the math right for the actual efficiency is around 65%. That is a bit of a difference between what Beer Smith gives me and what the numbers I just crunched gave me.

Lets see if I have this right.

OG 1.054
9.5 lbs of Pale 2 Row (Max PPG 38)
6.5 gallons wort collected

6.5 x 54 = 351
351 / 9.5 = 36.94
36.94 / 38(Max PPG) = 97%

I can live with that number. This is for determining approximate mash efficiency. Now using Palmer's method to determine actual efficiency, I get

38 x 9.5 = 361
361 / 6.5 = 55.53
36.94 / 55.53 = 66.5%

Seems odd that the software gives me one number, the estimated efficiency number gives me a 2nd, and the actual formula a third.

Maybe I am doing something wrong with the math here.

Maybe I should have some more beer to help me understand better.

 

[Echo2112]

DOH

Just realized what I was doing here.

Should be

9.5 x 38 / 6.5 = 55.53 (Max E)

54 (OG) / 55.53 (Max E) = 97.2%

That is a number I can live with. :cross:

 

[gxm]

Wow, 97%. Either your system is totally dialed in and awesome, or you made a mistake in the math.
If you post your raw data, we can be in awe of it :rockin:

 

[Echo2112]

I am hoping for awesome!

I brewed a Blonde Ale

9.5 lbs Pale 2 Row (US)
1 oz Cascade (boil @ 60 min)
1 oz Willamette (% min Aroma)
White Labs California Ale WLP 001 (1000ml starter)
2 lbs honey ( not used in boil - added to fermenter with yeast)

Grains were crushed at Austin Homebrew Supply

Got everything clean, warmed mash tun (10 gal round igloo) for 15 or 20 minutes.

Beer Smith called for 11.88 qts @ 171.3, I put in 3 gallons, since 2.97 seemed awkward to measure.

Held mash temp at 155 for 90 min. AHS said go 60, but I had read one of BierMunchers post on how he holds some of his mash times to 90 min to get better attenuation, so I figured why not.

Recirculated and drained first run, came out very clear, then sparged with 4.75 gallons @ 168 degrees.

Let sparge water sit for 15 min, then recirculated and drained into boil kettle with first run. Sparge looked great, clear runnings, like a cider color almost.

Gave me a total volume of 6.5 gallons, Beer Smith was estimating 6.34. Gravity was 1.054 going into the kettle.

Flame on, hit boil temp and pitched hops.

Flame off, chilled with copper coils, boil had taken volume down to 5.20 gallons.

OG from pot was 1.058, moved to primary, aerated for 45 min with air pump and 02 stone.

Added honey and yeast starter into 6.5 gallon glass primary with blowoff.

Fermentation started within a few hours, is now chugging along nicely with a big fluffy krausen on top.

 

[Bobby_M]

Something isn't right. 1.054 into the kettle at 6.5 gallons is 104%. Did you stir the wort in the kettle before drawing a sample?

 

[Echo2112]

I drew the sample after cold break and letting the trub settle, then just opened the valve on the pot and filled my thief with the hydrometer in it.

The math I did earlier gave this a Max efficiency of 55.53, so that would be 1.055 - 1.056 for the max OG right?

 

[Bobby_M]

Yeah, but what was the gravity before you started boiling?....when it was still 6.5 gallons.

Mash+lauter efficiency or "into the boiler" requires a gravity reading and volume reading for all the wort you collect but before you start boiling off.

Brewhouse or "into the fermenter" requires a gravity reading and volume reading after the wort is boiled and chilled.

It sounds like you might be mixing the chilled gravity reading with the preboil volume measurement.

 

[Echo2112]

The pre boil gravity was 1.054 with 6.5 gallons in the kettle. Reading was taken with a hydrometer in a thief, right from the boil kettle before I turned on the gas.

The liquid measure I got from the sight glass on the side of my kettle.

Same with the after boil volume, after I chilled, I took the volume reading from the sight glass, then took my hydro reading, which was 1.058.

 

[Bobby_M]

I think you pulled the sample for for preboil when it was still stratified because there's no way you boiled down from 6.5 to 5 gallons and only gained 1.004 in the process. I believe the 1.058 at 5 gallons because that's 87% per BTP.

 

[Echo2112]

So is the best thing to do to stir the wort some before the boil to take a reading? I wouldn't have thought to do that, since there was plenty of movement of the wort.

Also, does the temperature of the wort have an impact on the gravity reading?

 

[Echo2112]

Think I just found the answer to my own question.

I didn't let the wort cool off much when I took the pre boil gravity. So that has to be where the problem is. Guess I need to get a test stand and let the wort cool all the way down before I go writing down numbers and stuff.

 

[GilaMinumBeer]

BeerSmith and most any other software have compensation calculations for hydro readings at a known temp.

 

[SpanishCastleAle]

So which number is the one that is most important to consider?

While they are both important for the reasons mentioned, brewhouse efficiency ('into the fermenter') is the one that matters to me most. Because when you make your grain bill for future batches that's the number that tells you the predicted OG.

The mash efficiency ('into the boiler/kettle') is just an intermediate data point. And you need to know this so when you take your pre-boil gravity reading you'll know if you hit your mash efficiency or not and can adjust if you didn't (like adding DME if you were low).

 

[remilard]

Why would how much extract you leave in the kettle effect your OG?

If you switch from pellet hops to leaf, your brewhouse efficiency will decrease and your OG will not. You simply have less of the same wort in the carboy.

 

[SpanishCastleAle]

If you were asking me remilard...then I'm not understanding your question. You would have less volume of that same gravity wort (which means less total gravity points...i.e. less efficiency). Once you adjust your volume (by either boiling down more or adding water) then you change the gravity. I'm obv missing something in your question.

EDIT: I think I might see where our misunderstanding is. The way I do it the 'into the fermenter' volume is fixed/known. If I come up short I have to add water and if I come up high I'll have to boil it down more...but that final volume is 'non-negotiable'.
EDIT2: And I've never left any wort in the kettle...it all goes in (through a boiled strainer).

 

[AnOldUR]

While they are both important for the reasons mentioned, brewhouse efficiency ('into the fermenter') is the one that matters to me most. Because when you make your grain bill for future batches that's the number that tells you the predicted OG.

Is this backwards or is it just me?

Pre-boil tell you how well you used your grains. Into the fermenter tells you how much you wasted. The gravity stays proportional to the volume even if the efficiency does not.

 

[flyangler18]

Is this backwards or is it just me?

Pre-boil tell you how well you used your grains. Into the fermenter tells you how much you wasted. The gravity stays proportional to the volume even if the efficiency does not.

You're right, Herm. There's a confusion in terminology. Extract efficiency is the number that most of us are most concerned with relative to the poundage of grain required to achieve a pre-boil gravity; brewhouse efficiency is certainly important as, well, it means how much beer winds up in my belly!

Jason

 

[SpanishCastleAle]

The gravity stays proportional to the volume even if the efficiency does not.

Exactly...and the volume is fixed...we know that we are going to ferment (for example) 5 gallons. So since we know our volume and can measure the OG then we can determine our brewhouse efficiency. Then we can use our brewhouse efficency to use the exact correct amount of grains next time to achieve a wort of volume 5 gal. and OG - X.

In other words...how well I 'used the grains' is useful and nice to know...but I really want to know the OG and that encompasses the whole process. It accounts for all losses. To me it's the 'bottom line' as it were.

EDIT:

it means how much beer winds up in my belly!

And that's what I'm talkin' bout.

 

[flyangler18]

Exactly...and the volume is fixed...we know that we are going to ferment (for example) 5 gallons. So since we know our volume and can measure the OG then we can determine our brewhouse efficiency. Then we can use our brewhouse efficency to use the exact correct amount of grains next time to achieve a wort of volume 5 gal. and OG - X.

In other words...how well I 'used the grains' is useful and nice to know...but I really want to know the OG and that encompasses the whole process. It accounts for all losses. To me it's the 'bottom line' as it were.

Dunno, that seems like going up your arse to get to your elbow to me!

Jason

 

[SpanishCastleAle]

Lemme see if I can express myself more clearly.

You've sparged your grains and you have a preboil volume of let's say 6.5 gallons. You're planning a 5 gallon batch. You measure your preboil gravity and determine your mash efficiency...let's say you hit 85%. But this information doesn't tell you what your OG will be once you boil it down and add hops/etc. You won't know that unless you know your brewhouse efficiency. So you boil down your wort, add hops, etc. and then when you get to 5 gallons you chill and get it in the fermenter and measure your gravity. Your 'total' efficiency is no longer 85%...it's less. How much less? Depends on your brewhouse efficiency. You could never predict your OG from a given grain bill accurately unless you knew your brewhouse efficiency. That's why recipe calculators want to know brewhouse efficiency...not mash efficiency.

 

[GilaMinumBeer]

Often I have a nagging curiousity about how these programs are actually calculating. However, it hasn't nagged me enough to pull up to a pen, paper, and calculator.

So, you set you BHE to 75% (for example) and adjust your grain bill up to your desired target(s). This means you are already accepting losses and compensating for the known 25% efficiency loss.

You mash, sparge, and measure to find out your mash efficiency cam out as 90%.

So, what does this mean? Does it mean you obtained 90% of the total potential yield for the grist (90% of 100%) or does it mean you collected 90% of your 75% target (67.5%)?

Maybe I am just .

 

[SpanishCastleAle]

You mash, sparge, and measure to find out your mash efficiency cam out as 90%.

So, what does this mean? Does it mean you obtained 90% of the total potential yield for the grist (90% of 100%) or does it mean you collected 90% of your 75% target (67.5%)?

Gila,
Both mash and brewhouse efficiency are relative to theoretical 100% efficiency.

Often I have a nagging curiousity about how these programs are actually calculating. However, it hasn't nagged me enough to pull up to a pen, paper, and calculator.

I wrote my own about 12 years ago. If I know my brewhouse efficiency (and hit it) then my volume and OG are dead nuts everytime.

 

[GilaMinumBeer]

Gila,
Both mash and brewhouse efficiency are relative to theoretical 100% efficiency.

Yeah, I know that. But does BeerSmith know that?

 

[AnOldUR]

The point is that you shouldn’t be adjusting your grain bill because of something like boiling off too much or too little. If your mash efficiency is in-line and you still have a problem with OG you should be looking somewhere else in your process, not just throwing more or less grain into your tun.

 

[AnOldUR]

Mash efficiency is important because it is specific to one part of the process. Brewhouse efficiency it too broad and covers too many variables to be used for making adjustments. Anything you change based on brewhouse efficiency alone is just a guess.

 

[Bobby_M]

Let me try another way.

I'll set BTP to expect 85% brewhouse and expect 1.5 gallons per hour boiloff. From there, it tells me how much preboil I need and what the OG will be at that volume if I'm on target for 85%.

I pull all my preboil, confirm the volume (and fix it in BTP if I'm off), and then correct the efficiency until the preboil gravity matches what I got. The reason I care at this point is that if I'm off by more than 5 points, I may want to tweak my hop bill to maintain my desired GU:BU ratio.

 

[SpanishCastleAle]

The point is that you shouldn’t be adjusting your grain bill because of something like boiling off too much or too little. If your mash efficiency is in-line and you still have a problem with OG you should be looking somewhere else in your process, not just throwing more or less grain into your tun.

If you use whole hops they will absorb some wort so your brewhouse will ALWAYS be less than your mash efficiency (same gravity but less volume means less total points...i.e. lower efficiency). If you don't account for this your OG will be off. The beauty of brewhouse efficiency is that it won't matter if you boiled off too much (which would cause the OG to be too high)...you can just add water and your OG will be right where it's supposed to be. It has nothing to do with adjusting your grain bill to adjust for boiling off too much/too little...it has everything to do with adjusting your grain bill to account for losses...so your OG is right where you want it at your target fermenter volume.

 

[SpanishCastleAle]

Mash efficiency is important because it is specific to one part of the process. Brewhouse efficiency it too broad and covers too many variables to be used for making adjustments.

Probably a bad analogy but:

You are driving from Atlanta to LA...it would be nice to know how long it takes to get from Atlanta to Birmingham...then Birmingham to the Texas border...and so on so you can plan hotel/motel stays. But the 'bottom line' is how long it takes to get from Atlanta to LA. You might get slowed by a traffic accident or a flat tire or something else. Just adding up the theoretical travel times between cities and adding them all up won't account for these 'losses' (some of which are unavoidable).

Mash efficiency is just one 'stop' along the way (and a very important one). Brewhouse efficiency encompasses the whole process.

 

[Echo2112]

Good God, I come back in to check out my post and WOOSH!

Right over my head.


I am gonna have to go back and re-read all of this stuff a few dozen times to see if I can make sense of some of this.

 

[SpanishCastleAle]

Echo,
In addition to reading it...try to do the math yourself and I think you'll get a better understanding of it. Everybody has their own way of looking at things. I think we ('we'...meaning me and those having this last little discussion) probably agree on more than we disagree on this but we're probably approaching it from different perspectives.

Most of the difference between my mash efficiency and brewhouse efficiency is because I use whole hops. Whole hops absorb a significant amount of wort. If you had 5 gallons of 1.050 wort and then added hops, let them soak, and then removed them...they would absorb some wort and your volume would no longer be 5 gallons. But your gravity would still be 1.050. You just suffered a loss that your mash efficiency did not account for (because it happened afterwards). Now you'll have to add water to get back up to 5 gallons but that will lower your gravity. So you missed your target OG because you didn't account for losses that occured after the mash. Brewhouse efficiency takes ALL of this into account so you get your exact target OG at your exact target volume.

 

[Echo2112]

Thanks, that helps me understand things.

So what do you think is the best method for determining efficiency? Should I go with the numbers that Beer Smith is giving me? Or should I use the numbers and formula from Palmer's "How to Brew"?

I guess I can use both, but I am concerned about which is most accurate.

I realize one mistake I made was taking the pre-boil gravity while the wort was still pretty hot, so that threw the numbers off there, but my other numbers for the OG into the fermenter were dead on for temp, and that gives me an efficiency of 84%. I can live with that for now, next time, I know to refine a few steps.

Now,

As I understand it, you are using the "Into fermenter" gravity to help determine your grain bill, since you have a fixed variable with the volume of liquid, and you then insert the variable that is your target OG, and then use that to determine a grain bill.

That seems contradictory to what I have read, since as I understand it, the efficiency of your mash has an impact upon the amount of sugars in the wort pre-boil, and that during the boil, you are losing volume (Loss of H20) but the end result should be an increase in the concentrations of sugars, since you have not boiled them away, just the water. Which will result in an OG higher than the pre-boil gravity.

I would think that if you are less efficient in the mash, and you are correcting by adding DME to the boil to bring up the pre-boil gravity, you could be better served by correcting your mash schedule and try to get more sugars from the wort, rather than spending more money to cover for the lack of conversion.

Unless, of course I am still not understanding, which is possible.

 

[Echo2112]

Echo,
In addition to reading it...try to do the math yourself and I think you'll get a better understanding of it. Everybody has their own way of looking at things. I think we ('we'...meaning me and those having this last little discussion) probably agree on more than we disagree on this but we're probably approaching it from different perspectives.

Most of the difference between my mash efficiency and brewhouse efficiency is because I use whole hops. Whole hops absorb a significant amount of wort. If you had 5 gallons of 1.050 wort and then added hops, let them soak, and then removed them...they would absorb some wort and your volume would no longer be 5 gallons. But your gravity would still be 1.050. You just suffered a loss that your mash efficiency did not account for (because it happened afterwards). Now you'll have to add water to get back up to 5 gallons but that will lower your gravity. So you missed your target OG because you didn't account for losses that occured after the mash. Brewhouse efficiency takes ALL of this into account so you get your exact target OG at your exact target volume.

So could you not compensate for your whole hops by adjusting how much volume is left at the end of the boil? If you know that the hops are going to remove a certain amount of volume, wouldn't be better to adjust the boil times to allow for the loss, so when you transfer to the fermenter, you hit both the target OG and the target volume?

 

[AnOldUR]

Brewhouse efficiency is an important general tool that lets you know that there may be a problem in your process. Mash efficiency specific tool that lets you know if you are on the right track.

If I had the choice of only knowing only my mash or brewhouse efficiency I would choose to know the mash number.

If the mash efficiency is good and you adjust your boil for the correct OG the only potential problem is less volume. This could be due to hop absorbsion, excess break or loss of volume when trying to strain your wort into the fermenter. Although your brewhouse efficiency may suck and you have less beer, you still have good beer.

If you only look at brewhouse efficiency and adjust your boil for your desired OG, you still have the potential for over sparging and bad beer. Or you may be only fooling yourself with tons of break material and hop residue that will settle to the bottom of your fermenter and won’t actually give you any more beer in the end.

 

[AnOldUR]

If you use whole hops they will absorb some wort so your brewhouse will ALWAYS be less than your mash efficiency (same gravity but less volume means less total points...i.e. lower efficiency). If you don't account for this your OG will be off.

No. Your volume will be off. Your OG will only be off if you are foolish enough to use top off water.

The beauty of brewhouse efficiency is that it won't matter if you boiled off too much (which would cause the OG to be too high)...you can just add water and your OG will be right where it's supposed to be

Or you could adjust your boil for a reasonable amount of loss.

It has nothing to do with adjusting your grain bill to adjust for boiling off too much/too little...it has everything to do with adjusting your grain bill to account for losses...so your OG is right where you want it at your target fermenter volume.

So you would risk over sparging or wasting grain to get your desired OG.

Probably a bad analogy but:

No, actually a good one. Your choice is to leave earlier to make up for any problems that might be encountered along the way. I’d rather adjust my route to avoid delays.

 

[AnOldUR]

. . . wouldn't be better to adjust the boil times to allow for the loss, so when you transfer to the fermenter, you hit both the target OG and the target volume?

No, you need a set boil time to get proper hop utilization and to remove unwanted compounds. If you want to hit the right volume you have to increase both your grain bill and the amount of sparge water used so that you have more going into the kettle. You have to keep that ratio right for proper mash efficiency. Your brewhouse efficiency may suck, but you'll have the right amount of beer and you'll have good beer.

 

[Echo2112]

Brewhouse efficiency is an important general tool that lets you know that there may be a problem in your process. Mash efficiency specific tool that lets you know if you are on the right track.

If I had the choice of only knowing only my mash or brewhouse efficiency I would choose to know the mash number.

If the mash efficiency is good and you adjust your boil for the correct OG the only potential problem is less volume. This could be due to hop absorbsion, excess break or loss of volume when trying to strain your wort into the fermenter. Although your brewhouse efficiency may suck and you have less beer, you still have good beer.

If you only look at brewhouse efficiency and adjust your boil for your desired OG, you still have the potential for over sparging and bad beer. Or you may be only fooling yourself with tons of break material and hop residue that will settle to the bottom of your fermenter and won’t actually give you any more beer in the end.

Thanks!

And just to be sure I have this set right, over sparging can lead to tannin extraction, which will give me flavors I don't want in my wort. And that normally will occur only after the pre boil gravity has gotten fairly low, under 1.010 or so correct?

I figured that you had to get the mash right, and shoot for a good efficiency in order to get the wort right for the type of beer you were making. While it is good to know how efficient you were at the end of the boil, the quality of the mash is a more important factor in determining the quality of the final product.