I hate beersmith brewhouse efficiency

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I have been using beersmith 2.0 for about 2 years now and I just don't get brewhouse efficiency and how to use it to accurately hit my OG. For today's brew session (Lemon Weiss) here are the numbers:

Pre-boil volume = 8.11 gal
Pre-boil gravity = 1.041
Mash efficiency = 75% (estimated was 74%)

So I am mashing as predicted based on my system.
Then when I go to boil I hit my post boil volume numbers but my OG is always less than that beersmith predicts.

My OG for this batch was 1.05 with a post-boil volume of 6.5gal.
After cooling I transferred 5.5gal in the fermenter (0.5 shrinkage, 0.5 trub).

So I put in beersmith that the batch size is 5.5gal and my OG is 1.05 and my brewhouse efficiency is 63% not the predicted 70% efficiency it says it should be. Based on the 70% efficiency my OG should be 1.055

What am I doing wrong? Or is it just a matter of how beersmith uses "batch size". If I put these same measurements in brewers friend, it says with a gravity of 1.04 at 8.11 I should hit 1.05 at 6.5 which I did. But because 5.5gal goes into the fermenter, somehow that changes my OG?
 
Beersmith data is only as accurate as the numbers you feed it. An immediate red flag here is the large amount you are attributing to shrinkage. That is significantly higher than 4% from boiling to final temps. Your 0.5 gallon is closer to 9%

My shrinkage for 5.5 gallon batches to FV is set at 4% less than half of yours.

That is what sticks out to me. You need to account for the changes if volume to FV is correct than you are losing the extra to trub in the kettle or dead loss in hoses.

Calculate this value and change shrinkage to 4% and see what happens

I love Beersmith but accurate measures are a prerequisite to its accuracy
 
Gavin is correct about your shrinkage number. I do a 'sanity' check on my pre- and post- boil volumes by calculating the gravity points before and after boiling. They should work out to within your measurement error of each other.
 
I have calculated my volumes pretty accurately. When I bought my brew pot or any brewpot I use I measure with a ruler in 0.5gal increments up to 10gal. I then use excel to generate a standard curve which can be used to calculate any number on that scale. I always measure my volume post boil and post-cooling and my shrinkage is accurate.

If you are thinking that I have more volume than I think I have (or that beersmith things I have), I don't think that is it but I will definitely check again using my ruler system.

I have a very large brewpot (about a 48qt) and it is pretty wide compared to most brew pots, so my boil off rate is pretty hight 1.65gal/hr and the shrinkage rate is pretty high (0.5gal).
 
Can you list out the measured volumes and measured gravities vs the beersmith predictions. It's hard to follow in the text

Edit: shrinkage volume is based on the properties of water, not your pot, and is the same for everyone
 
Shrinkage has nothing to do with pot size. It is a variable determined by temperature change and pressure.

The shrinkage of water at habitable altitudes going from 212f to 70 f ish will be 4%. Your figure if correct implies your water is behaving differently to the other water in the universe.

If your water doesn't have strange properties your measure is wrong. These are the two possibilities.
 
The other possibility is inaccuracy of the preboil OG due to taking it at a higher temperature than about 90 degrees. In order for an accurate reading with a hydrometer, the reading must be cooled to under 100 degrees and then the reading taken and the corrections made. If the reading is with a refractometer, it needs to be corrected with the 'hydrometer correction factor' to get the SG.
 
Gravity readings at the calibration temp of the hydrometer eliminate any errors of this nature. One more way to help. I take a preboil reading and stick it in the fridge after running the tube Under cold water for a bit.

The temeprature correction tools only seem to be good within a small range of calibration temps so I just eliminate their use entirely. Doesn't add any time to a brewday.

Again correct measures fed to the software being the salient point.

Measure temperature of a sample.

image.jpg
 
Shrinkage has nothing to do with pot size.

Is this true? I thought that a wider pot, with a larger surface of liquid, led to greater boil off, but perhaps this is one of the new things I learn today. For what its worth, using a 20 gallon brew pot, I get 2 gallons of boil off.
 
This is true. Shrinkage of water is a physical property independent of what shape or size object is housing it. The molecules are not aware of the vessel parameters.

Boil off is quite a different process with a myriad of extra-liquid factors affecting the value
 
I find BeerSmith's "brewhouse efficiency" to be really awkward and easy to mess up. The way I think of it, brewhouse efficiency has more to do with hitting target fermenter volume than it does with hitting target gravity. It's how little loss to deadspace in the hlt/mlt/kettle/tubing/chiller/trub etc that you have. Mash efficiency, however, is more about gravity.

My solution is to set my brewhouse efficiency to my mash efficiency (85%). I then zero out any and all trub losses (only factor is thermal expansion of wort, which like others have said I set at 4%) and factor those in my head. I'm more concerned with gravity than I am with batch size, so I'm not worried if they're a bit off, and experience has always told me that depending on changes in hop bills, grain bills, batch size, batch gravity, grain types, etc, the trub amounts are always different anyway, so it's kind of pointless to have BeerSmith set a number for them to begin with.

I then set my batch size as my post-boil, post-chill volume, and NOT my fermenter volume. Now, if you're using a plate chiller or something else (I use an immersion chiller) where you're not chilling in the kettle, then it may not work as well for you. But if you know your boiloff well enough then it really shouldn't matter. But this way, I hit my numbers dead on just about every time (or at least +/- 0.2P).
 
The problem with the focus on brewhouse efficiency is that it does not take into account the differential results of brewing high gravity vs low gravity nor low hop rate vs high hop rate. After 78 brews using beersmith and going through the post brew calculations, I can very accurately pin down my mash efficiency as a function of target OG. Likewise, I can dial in trub loss vs hop addition (I don't use a hop bag).

I set my profiles to the median values for what I brew with the target of a mash efficiency. When developing a recipe or going to brew a recipe, I set the trub based upon what my history indicates, and adjust the brewhouse efficiency to bring the mash efficiency to where I know it will be based upon my past experience.
 
I'll try and address all the responses, and thank you all for the help.

Overall, yes I know brewhouse efficiency is not that big a deal as long as I am making good beer. All-in-all I am hitting my numbers and my beer is mighty tasty, which is the reason I brew.

But...

Pot measurements: Like I said before, I've calibrated my pots with a ruler and made a standard curve so I can accurately (or get a pretty good average) the volume in the pot with a reading on a ruler. I know my pre-boil and post-boil volumes are correct. I just re-calibrated it this afternoon and my numbers are good.

Boil off is different than shrinkage. I am just talking about boil-off. I hit 1.65gal per hour. Simply, I take the measurement pre-boil, then right at flame out I take a measurement and my volumes are good.

Then after chilling the wort down to pitching temp I can take another measurement before I rack to the fermenter. The difference in the post-boil volume and the new volume is the amount lost due to shrinkage. I am averaging 0.5gal after cooling (about 7.5% for me).

Hydrometer readings. After mashing I take a hydrometer reading (not refractometer, I don't have one). I put the wort in a glass and use a small ice bath to get it down to ~65deg and take my reading. So it is not hot wort. My pre-boil gravity always hits my beersmith 2 predicted gravity within a couple of points.

What is happening though is after the entire brew day my volumes seem accurate but my OG is lower by 5 points or so. If beersmith volumes and my volumes are in agreement, and if I am hitting my mash gravities as beersmith predicts, where did the sugar go? I think it has to do with how beersmith is using batch size. Again, an example from my brew day yesterday.

Beersmith predications:
pre-boil volume = 8.1 gal
pre-boil gravity = 1.041
measured pre-boil gravity = 1.04
end of boil volume = 6.45gal
measured end of boil volume = 6.45gal
batch size 5.5gal (into fermenter)
predicted batch OG = 1.055
measured OG of wort after cooling = 1.050

So I'm off by .005. But if you go into beersmith and change the batch size to 6.5gal (because the entire wort in the pot is 6.5gal) then the predicted OG is 1.046 and so I am over.

I guess the question boils (ha!) down to is how beersmith uses batch sizes and volumes to calculate efficiency and whether or not it matters. If I have 6.5 gal of wort that is 1.050, regardless of whether I ferment 5gal or 6gal, the OG is still 1.050. Right?

This is what annoys me with beersmith. Ultimately it doesn't matter if I can get around the number because it's just me drinking it and I'm not selling this for profit, but I would like to know that the recipe I'm putting together is going to be accurate.

I hope that makes sense. I know I've opened the typical "what is batch size" argument, but I think I am messing up somewhere in software.

Thank you all for the suggestions. I'll keep plugging away at it. The nice thing is in order to keep dialing in my system I need to brew some more! :)
 
In your equipment profile do you have your "loss to Trub and Chiller" (in the boil pot) set to 1g which is about the difference between your Post boil and Batch Size?

Also I would return your shrinkage to 4% unless you are weighing your water to determine a precise volume.
 
Just to reiterate. Shrinkage set at a value different to what is by and large a physical constant will introduce error. Either the universal laws governing the physical properties of water are wrong or your measures are.

Beersmith is a tool. I would suggest an extremely useful one. Like any tool is is subject to user error and measurement error. Once you get these ironed out and reduced I think it will give you projected data closely matching what you are seeing.
 
In your equipment profile do you have your "loss to Trub and Chiller" (in the boil pot) set to 1g which is about the difference between your Post boil and Batch Size?

Also I would return your shrinkage to 4% unless you are weighing your water to determine a precise volume.

My loss to trub and chiller was set to 0.5g because after chilling I usually lose about 0.5g due to shrinkage. I will try what you and Gavin have suggested, change shrinkage back to 4%, maybe bump up the loss to trub and chiller to 1g and see how that affects my numbers. Thanks so much!

I agree that beersmith is a great tool, I really love it. I'm not all too concerned with awesome efficiencies because of the small scale I am on, but would like better accuracy in hitting OG values.
 
I'll try and address all the responses, and thank you all for the help.

Overall, yes I know brewhouse efficiency is not that big a deal as long as I am making good beer. All-in-all I am hitting my numbers and my beer is mighty tasty, which is the reason I brew.

But...

Pot measurements: Like I said before, I've calibrated my pots with a ruler and made a standard curve so I can accurately (or get a pretty good average) the volume in the pot with a reading on a ruler. I know my pre-boil and post-boil volumes are correct. I just re-calibrated it this afternoon and my numbers are good.

Boil off is different than shrinkage. I am just talking about boil-off. I hit 1.65gal per hour. Simply, I take the measurement pre-boil, then right at flame out I take a measurement and my volumes are good.

Then after chilling the wort down to pitching temp I can take another measurement before I rack to the fermenter. The difference in the post-boil volume and the new volume is the amount lost due to shrinkage. I am averaging 0.5gal after cooling (about 7.5% for me).

Hydrometer readings. After mashing I take a hydrometer reading (not refractometer, I don't have one). I put the wort in a glass and use a small ice bath to get it down to ~65deg and take my reading. So it is not hot wort. My pre-boil gravity always hits my beersmith 2 predicted gravity within a couple of points.

What is happening though is after the entire brew day my volumes seem accurate but my OG is lower by 5 points or so. If beersmith volumes and my volumes are in agreement, and if I am hitting my mash gravities as beersmith predicts, where did the sugar go? I think it has to do with how beersmith is using batch size. Again, an example from my brew day yesterday.

Beersmith predications:
pre-boil volume = 8.1 gal
pre-boil gravity = 1.041
measured pre-boil gravity = 1.04
end of boil volume = 6.45gal
measured end of boil volume = 6.45gal
batch size 5.5gal (into fermenter)
predicted batch OG = 1.055
measured OG of wort after cooling = 1.050

So I'm off by .005. But if you go into beersmith and change the batch size to 6.5gal (because the entire wort in the pot is 6.5gal) then the predicted OG is 1.046 and so I am over.

I guess the question boils (ha!) down to is how beersmith uses batch sizes and volumes to calculate efficiency and whether or not it matters. If I have 6.5 gal of wort that is 1.050, regardless of whether I ferment 5gal or 6gal, the OG is still 1.050. Right?

This is what annoys me with beersmith. Ultimately it doesn't matter if I can get around the number because it's just me drinking it and I'm not selling this for profit, but I would like to know that the recipe I'm putting together is going to be accurate.

I hope that makes sense. I know I've opened the typical "what is batch size" argument, but I think I am messing up somewhere in software.

Thank you all for the suggestions. I'll keep plugging away at it. The nice thing is in order to keep dialing in my system I need to brew some more! :)


How many total gravity points do you yourself calculate as potential? I like to start with that number. I.E 10 LBs of two row at 36 points per LB potential gravity = 360 total possible points. Then take a gravity reading from your well mixed pre-boil wort. If your hydrometer is accurate and you have measured your volumes correctly; you now can calculate how much sugar you managed to extract from the grain, this value will not change. Say you now have 8 gallons of 1.036 wort. Your total sugars would be 8x36=288, 288/360 = 80% efficiency. Your calculated amount of sugar will not vary from that 288 no matter what your final volume is. You can therefore correct any volume deficiencies (due to boiling off more liquid than you thought you would) by topping off in the last 15 or so minutes of boil. And if your total sugars are not high enough to give you both desired final volume and gravity, you can add more fermentable in that last 15 minutes (DME, Table Sugar, Honey, LME). In this manner you can correct for either deficiency.
 
How many total gravity points do you yourself calculate as potential? I like to start with that number. I.E 10 LBs of two row at 36 points per LB potential gravity = 360 total possible points. Then take a gravity reading from your well mixed pre-boil wort. If your hydrometer is accurate and you have measured your volumes correctly; you now can calculate how much sugar you managed to extract from the grain, this value will not change. Say you now have 8 gallons of 1.036 wort. Your total sugars would be 8x36=288, 288/360 = 80% efficiency. Your calculated amount of sugar will not vary from that 288 no matter what your final volume is. You can therefore correct any volume deficiencies (due to boiling off more liquid than you thought you would) by topping off in the last 15 or so minutes of boil. And if your total sugars are not high enough to give you both desired final volume and gravity, you can add more fermentable in that last 15 minutes (DME, Table Sugar, Honey, LME). In this manner you can correct for either deficiency.

This is correct only if you adjust for pre boil volumetric shrinkage and account for all other volume losses if any are present. They usually are if you are using hops. Other losses would be to a plate chiller, hoses, spills, wort left in kettle.

Adding sugar would not be something I would do unless it was in recipe.
 
If there is loss somewhere in the system then my statement would not hold true. I squeeze my hop bags and dump the entire amount of the kettle (minus perhaps a cup of stuff) into my fermenter. So for each person and their setup, they would have to take into account any losses (hoses, spills, kettle remnants). All the stuff from the kettle ends up at the bottom of the fermenter with the yeast. Any of the solids and yeast then must be subtracted in ones calculations.
One could still use the previous calculations and then figure the difference in yield, if that difference stays consistent (from loss, in hoses or what not), then it could be quantified and adjustments made to still hit desired volume and gravity.
In this instance the loss of 5 gravity points per gallon could be made up for easily by adding a pound of grain,+1 pint of water loss to the grain. Then the boiled off water could be made up for and desired outcome achived.
 
If there is loss somewhere in the system then my statement would not hold true. I squeeze my hop bags and dump the entire amount of the kettle (minus perhaps a cup of stuff) into my fermenter. So for each person and their setup, they would have to take into account any losses (hoses, spills, kettle remnants). All the stuff from the kettle ends up at the bottom of the fermenter with the yeast. Any of the solids and yeast then must be subtracted in ones calculations.
One could still use the previous calculations and then figure the difference in yield, if that difference stays consistent (from loss, in hoses or what not), then it could be quantified and adjustments made to still hit desired volume and gravity.
In this instance the loss of 5 gravity points per gallon could be made up for easily by adding a pound of grain,+1 pint of water loss to the grain. Then the boiled off water could be made up for and desired outcome achived.

His point is that if you don't adjust the volume of your preboil reading for temperature (not just the temperature of the gravity sample), you'll have the volume part of the equation slightly wrong.

As has been said already though, the difference between pitching temp/room temp and boiling is only ~4%, and at mash/sparge temp where a pre-boil reading is taken, the difference is even less. I don't bother correcting it, since there's a margin of error for mixing of mash and sparge runnings anyway, and a <4% difference may not be worth differentiating.

But yes, like you, I don't factor fermenter volume, only the actual volume in the kettle. If you have losses post boil, they will not impact your gravity, only your volume, and the BeerSmith math with this stuff is very particular, so I make sure that BeerSmith doesn't touch it. I just factor that on my own. My primary concern is hitting my gravity- BeerSmith helps there. The volumes, I know my equipment so I know what I need to do and where I"ll end up.
 
Think of efficiency as just tracking total sugar and not gravity. Every time you lose sugar (left behind in grains, left behind in trub), your brew house efficiency goes down. As you lose volume (boiling, left behind in trub, "shrinkage") your gravity will change accordingly, but has nothing to do directly with efficiency. So when boiling: sugar stays the same, volume goes down and thus gravity goes up. As you leave behind trub: sugar level goes down, volume goes down, gravity stays the same.

Extreme example. You boil and cool 5 gallons of wort. You make beer with 1 gallon of it and dump 4 down the drain. Your mash efficiency was the same for both, and your gravity of each is the same, but since your loss of 4 gallons was so high, your Brewhouse efficiency is no good
 
I find BeerSmith's "brewhouse efficiency" to be really awkward and easy to mess up. The way I think of it, brewhouse efficiency has more to do with hitting target fermenter volume than it does with hitting target gravity. It's how little loss to deadspace in the hlt/mlt/kettle/tubing/chiller/trub etc that you have. Mash efficiency, however, is more about gravity.

My solution is to set my brewhouse efficiency to my mash efficiency (85%). I then zero out any and all trub losses (only factor is thermal expansion of wort, which like others have said I set at 4%) and factor those in my head. I'm more concerned with gravity than I am with batch size, so I'm not worried if they're a bit off, and experience has always told me that depending on changes in hop bills, grain bills, batch size, batch gravity, grain types, etc, the trub amounts are always different anyway, so it's kind of pointless to have BeerSmith set a number for them to begin with.

I then set my batch size as my post-boil, post-chill volume, and NOT my fermenter volume. Now, if you're using a plate chiller or something else (I use an immersion chiller) where you're not chilling in the kettle, then it may not work as well for you. But if you know your boiloff well enough then it really shouldn't matter. But this way, I hit my numbers dead on just about every time (or at least +/- 0.2P).

Exactly what I do.

I have calculated my volumes pretty accurately. When I bought my brew pot or any brewpot I use I measure with a ruler in 0.5gal increments up to 10gal. I then use excel to generate a standard curve which can be used to calculate any number on that scale.

Why are you calculating your volume with a ruler? I highly doubt your pot has perfectly parallel sides with perfect 90 deg. bottom edges.
 
Exactly what I do.



Why are you calculating your volume with a ruler? I highly doubt your pot has perfectly parallel sides with perfect 90 deg. bottom edges.

I did the marked mash paddle for a while, until the etch-your-own-kettle process surfaced. Same idea. As long as you're calibrating with accurate volume no reason it can't work.
 

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