Unusually high efficiency. is 104% into boiler even possible?

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stevea1210

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Let me start by saying that I double checked every one of my readings, and am extremely confident that the readings are not a mistake. That being said, what went on today with my efficiancy?

I brewed Jamils dark mild, set with my normal brewhouse efficiancy of 71%. I checked my "efficiancy into boiler" in beersmith, and it was 104%!! WTF. I ended up with 8.25 gal of wort at 1.031. Like I said I double checked all of the measurements and data entries, and it came up the same. At the end of the brew, my OG was 1.043 (expected 1.033), with a brewhouse efficiancy of 87.5%. That is the highest efficiancy I have ever had.

Some things worth noting:
crush shouldn't be an issue, as I bought three batches the same day, at the same place, using the same mill and the efficiancy on the other 2 were 69% and 71% (which is my avg).

equipment was definitely different on this batch. I followed flyguy's tutorial for cooler conversion on my 5 gal igloo. I didn't want to use my 10 gal since it was such a small grain bill (6.75 lbs). It is using a stainless braid.

I got a new 15 gal brew pot, and today was the inagural run. Having the bigger kettle did allow me to collect more wort, which should have helped my efficiancy some, but I didn't think that much.

So is 104% even acheivable? Logic tells me the only ways were if the gravity reading was wrong, the volume reading was wrong, or the grain bill was larger than entered into beersmith. I anticipated an improvement in efficiancy with the ability to collect more wort, but brewhouse from 71% to 87%? And the 104% into boiler is driving me crazy. I'm happy that my efficiancy improved, but that was one hell of a jump.

Do you guys have any ideas on this?
 

r2eng

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1. Recipe may have been entered wrong
2. 104% is impossible
3. If you mean you hit 87% efficiency, sure! NP. Great job! If the 104% was a "post boil", you just cooked out more water. I use Beersmith, but am not familiar with the efficiency to boiler section.

I think something was entered wrong in Beersmith. May want to post in the software section of the forum.
 

The Pol

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Yeah, 104% is impossible. You cannot extract more sugars than the grain has potential to provide. Something is wrong, but who knows what?
 

ChemE

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What was the temperature of the pre-boil wort? I'm guessing somewhere around 175F if you fly sparged. 1 gallon of 175F water is actually only 0.973 gallons at 60F which is where your hydrometer is likely calibrated.

Your 8.25 gallons of pre-boil wort would only be 8.03 gallons at 60F which would drop your efficiency into your boiler down to 99.7%.
 
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stevea1210

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The 87% was post boil, the 104% pre boil. Yeah I am stoked if I can maintain an efficiency like that.

I agree that you can't get more than there is to give. I didn't think more than 100% would work.

@cheme
learn something new everyday. The temp would have been in that range, probably a little less than that. I double batch sparge with 180f water. Even taking that into account 99.7% is still out of this world.

for those of you that have gotten high 80's for efficiency before, what does your pre boil efficiency average?
 

ChemE

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The 87% was post boil, the 104% pre boil. Yeah I am stoked if I can maintain an efficiency like that.

I agree that you can't get more than there is to give. I didn't think more than 100% would work.

@cheme
learn something new everyday. The temp would have been in that range, probably a little less than that. I double batch sparge with 180f water. Even taking that into account 99.7% is still out of this world.

for those of you that have gotten high 80's for efficiency before, what does your pre boil efficiency average?
Did you discard any trub/wort going from the boiler to the fermenter? I'm assuming so but if not it calls into question your pre-boil measurements.

My pre-boil efficiency is usually around 93% and my brewhouse clocks in at 92%.
 
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stevea1210

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Did you discard any trub/wort going from the boiler to the fermenter? I'm assuming so but if not it calls into question your pre-boil measurements.
Usually I do leave some behind, but today wasn't 'usual'. I didn't originally intend on collecting that much wort. I had to boil longer than normal to get it down to volume (looking for 5.25 gal).

Well Just as I was getting ready to throw the IC in to the brewpot I came across a slight issue. My hose was frozen solid. I hooked it up to my sink with hot water, and thawed it out. That extra time, and I ended up with 5 gal in the fermenter using everything from the kettle.

How does that call into question my measurements? I don't follow.
 

ChemE

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Disclaimer:
As others have mentioned repeatedly on other threads, BeerSmith's efficiency calculations are oddly named and just generally confusing, so I'll go through everything by hand in an effort to maintain clarity.

Theoretically Available Sugar
According to the recipe you have the following sugar available:

5# Pale British Malt (assume MO) = 5(38 ppg) = 190 ppg
0.5# Chocolate = 0.5(28) = 14 ppg
0.75# Crystal 60 = 0.75(34) = 25.5 ppg
0.5# Crystal 120 = 0.5(33) = 16.5
6.75# Total grain = 190 + 14 + 17 + 24.75 = 246 ppg

Mash/Lauter Efficiency
We already determined that you collected 8.03 gallons (volume corrected to 60F) of 1.031 into your boiler so your mash/lauter efficiency is:

8.03(31)/246 = 101.2%*
* This differs from my above post because I had previously assumed 6.75# of MO for a quick calculation.

Brewhouse Efficiency
This is why I mentioned that 100% transfer of wort into your fermenter calls into question you pre-boil measurements. Since you didn't discard any trub/wort, you maintained a closed system and there is nowhere for the sugar to have gone. 100% of the sugar which made it into the boiler should have been transferred to the fermenter. You mentioned you collected 5.0 gallons of 1.043 into the fermenter which give a brewhouse efficiency of:

5(43)/246 = 87.4%

Analysis
Somehow you lost quite a bit of sugar between the boiler and the fermenter yet you say you didn't discard/waste any wort. If you had kept all the sugar measured into the boiler, you would have produced 5 gallons of 1.051 wort. So unless you did waste a significant amount of wort, one of your sets of measurements is off. My bet would be on the pre-boil measurements since they produce a result which is extremely unlikely.
 

Kaiser

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How did you cool down the sample for the pre boil gravity reading or are you using a refractometer?

Kai
 

Bokonon

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I got a new 15 gal brew pot, and today was the inagural run. Having the bigger kettle did allow me to collect more wort, which should have helped my efficiancy some, but I didn't think that much.
This jumped out at me as a potential issue here. Since this was your first run on your 15 gal brew pot are you certain that your volumes are calibrated accurately?
 
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stevea1210

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Thanks ChemE, great explanation start to finish. I did not mention that I pulled out how to brew to manually dbl check the numbers that beer smith gave me. My calculation (only did the pre boil by hand), came out to the 104, but I used the 8.25 gal, not 8.03.

Now I understand what you meant about calling them into question. To be more specific on any wort loss, there was two hydro samples taken, and I use a hanging hop sock, so the wort that was absorbed by the 1 oz of EKG. In addition there was approximately 12 oz (eyeballed, not measured) in the kettle that I did not transfer. A relatively small % of total volume, but it is some.

I have to agree with your analysis that there must be something wrong with the pre-boil measurement. I'm still not sure what the culprit is, but it is the most logical.

Do you recommend temp correcting the volume of pre boil wort prior to putting that into beersmith? I have never done that. I always temp correct my hydro reading, but never the total volume.
 
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stevea1210

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I cool down the hydro samples by placing the testing cylinder in an ice h20 bath. Any difference in temp from the calibration of the hydrometer (60F) is corrected using the tool in beersmith. The hydro readings I have mentioned in this thread have all been corrected in that manner.

The new brew kettle volumes were measured by adding 1 gal of water to the kettle, and marking the water level on a pvc pipe. I repeated the process up to the 14 gallon mark. I have a 4 quart measuring cup I picked up from the restaurant supply store, so the one gallon measurements are pretty accurate. This was done before brewing with plain water.
 

ChemE

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Okay, so the approximate 12 ounce loss in the boil kettle accounts for:

0.09375(43) = 4.03 points which represents a
4.03/245.75 = 1.64% loss of efficiency

So we can get from the 87.5% brewhouse efficiency to an 89.14 mash/lauter efficiency but we're still missing a good deal of sugar if all measurements are to be believed.

It seems that BeerSmith attempts to temperature correct volumes because it has a 4% cooling loss programmed in to help predict boil volume, but it doesn't appear to take this into account for efficiency. BS must think or require that volumes input into efficiency be temperature corrected by the brewer, so I would recommend you correct manually.
 

pjj2ba

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One thing to consider is experimental error, not as in, a mistake was made, more like how accurate your measuring devices are, like many dial thermometers being plus or minus 2 F (150 F could in reality be anywhere from 148 to 152). 3% could be simply within the margin of error.

It is possible to get 100% conversion in the mash tun. After that it all goes down hill. Some is lost to the sparge, left in the boil kettle, etc, all being subtracted from 100% to give you your brewhouse efficiency.
 

iamjonsharp

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Let's see:

Efficiency = gravity * volume / lbs of grain / points per lbs of grain (PPG)

If you assumed:
points per lb of grain = 36 PPG
lbs = 6.75 lbs of grain

If you measured:
Volume = 8.25 gallons
OG = 31 points

Efficiency = 105%

But wait! What if.....

PPG was actually 37 (2.5% error)
lbs of grains used was actually 7 lbs of grain (3.5% error)

Volume was actually 8 gallons (3% error)
Original gravity was actually 30 points (3% error)

Actual Efficiency = 93% (11% error)

Small errors from your assumptions (PPG) or measurements (gravity, volume, lbs of grain) can lead to much larger errors in calculating actual efficiency.
 

Joe Camel

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Rather than worrying about the 104% efficiency, crow about 88% final efficiency, that's a great result no matter how you got there.

It is most likely that it's the volume measurements that are the culprit, I used a 4L pitcher with graduations every half liter when I started, then found out that the marks were off by almost a half liter, which compounded the error every time I filled it. If you have a good scale, even a digital bathroom scale will work, fill a 5-gallon bucket in 1 liter increments with water (1L of water weighs 1kg, yay metric system) and make marks on a stick or a spare piece of copper pipe. Now you have a calibrated measuring system. Batch sparge into the bucket, measure volume with stick, transfer to pot and repeat.
You can calibrate your pot the same way, some folks sparge directly into the pot, I like to keep my runnings separate for my notes.

You can do the same thing if you want to work in gallons, 1 gallon of water weighs 8.45 pounds

Cheers
 

ChemE

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..You can do the same thing if you want to work in gallons, 1 gallon of water weighs 8.45 pounds

Cheers
Almost, a US gallon of water weighs 8.34 pounds at 39.2°F (4°C). An imperial gallon of water weighs 10.02 pounds at 39.2°F (4°C). At 68°F (20°C) a US gallon of pure water weighs 8.33 pounds.
 
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stevea1210

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@Joe Camel - don't get me wrong, I was thrilled to see that jump in efficiency. I was very happy to see that. Anomalies like the 104% grab my attention though :).

@pjj2ba and iamjonsharp

you guys hit on something I hadn't considered. While I can try to be as accurate as possible, I can't guarantee 100% accuracy. Even if I am off by only 2-3% as you mentioned, it could add up pretty quick.

Your example shows how that small difference, could add up. I guess I never looked into this before, since my efficiency into the boiler never stood out to me before.

I guess the big question now is, can I maintain this efficiency going forward?!?!?
 
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correct me if I'm wrong - but aren't PGGs calculated by assuming what you're likely to extract from the grain

Example - let's say there's 10 grams of sugar in a said amount of grain. Since it's basically impossible to extract all 10 grams, the PPG of the grain is 9 grams. But, for whatever reason, if you extract that extra gram of sugar, your efficiency is over 100%. PPG is 9 grams, but you actually got 10

Does anyone follow that? Or am I :drunk:
 

iamjonsharp

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I guess the big question now is, can I maintain this efficiency going forward?!?!?
It looks like you got a really high efficiency for a couple reasons (that I can see based on information given, or info I've picked up): you sparged more than normal, and you brewed a lower OG beer. These will both result in a higher efficiency, because you are rinsing more sugars from your grains.

The most important part is not a high efficiency but consistently hitting your target OG.
 

iamjonsharp

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correct me if I'm wrong - but aren't PGGs calculated by assuming what you're likely to extract from the grain

Example - let's say there's 10 grams of sugar in a said amount of grain. Since it's basically impossible to extract all 10 grams, the PPG of the grain is 9 grams. But, for whatever reason, if you extract that extra gram of sugar, your efficiency is over 100%. PPG is 9 grams, but you actually got 10

Does anyone follow that? Or am I :drunk:
The maltster should provide the information for PPG, which is based probably on the median or average of a range of PPGs calculated during testing of the malt. The maltster may provide a value of 36 PPG, but perhaps the malt you get and use actually provides you with 37 PPG. You aren't getting an efficiency of greater than 100%, it's just that your grain achieves better PPG than the average PPG assigned to the grain.
 
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The maltster should provide the information for PPG, which is based probably on the median or average of a range of PPGs calculated during testing of the malt. The maltster may provide a value of 36 PPG, but perhaps the malt you get and use actually provides you with 37 PPG. You aren't getting an efficiency of greater than 100%, it's just that your grain achieves better PPG than the average PPG assigned to the grain.
Thank you - you explained what I was trying to say in a much better way.
 

GilaMinumBeer

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The maltster should provide the information for PPG, which is based probably on the median or average of a range of PPGs calculated during testing of the malt. The maltster may provide a value of 36 PPG, but perhaps the malt you get and use actually provides you with 37 PPG. You aren't getting an efficiency of greater than 100%, it's just that your grain achieves better PPG than the average PPG assigned to the grain.
Exactly! Very few of us get the actual batch analysis for each grain use. For the most part we tend to use the numbers provided in the software and take them as gospel. You gotta remember that at best we are getting an Average extract potential and the avg ext pot may not be keyed accurate for the grain you are using.
 

Joe Camel

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Yes, that is a possible explanation, but if you review BrauKaiser's calculations on batch sparging, there is a limitation to how much sugar you can extract from your grainbed, 2 sparges and first runnings should max out around 90% lauter efficiency. Since efficiency into the boiler is the product of lauter and mash efficiency, you'd need a mash efficiency of 116% to get 104% into the boiler. 36ppg *116% is 42ppg, that's practically mashing pure sugar.

I think the most reasonable explanation is that the volume collected into the pot was overestimated by a few liters. This would yield an error in the calculation that would give 104%.

In my last few batches, I've seen a drop of about 5% between boil and brewhouse efficiency to account for the volume loss in the trub. A 17% drop would mean a very significant volume of wort was left in the pot, almost a gallon. This wasn't noted in the first post, so I'm thinking the volume measurement was off by a gallon or so

Cheers
 

Bobby_M

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It hasn't been mentioned yet, but I think you took your preboil gravity sample out of the kettle when it was still somewhat stratified. So many extract noobs have the same problem measuring OG when they add their topoff water and don't stir it in well.

If I'm right, you sampled from a pocket of slightly more concentrated wort giving you a false high reading preboil. After the boil, it was homogeneous and a valid sample. 87% brewhouse is just about perfect as far as I'm concerned. That's what I shoot for.

That's not to say you didn't also mistake your volume measurements slightly, but I'm betting on stratified wort.
 

broadbill

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I think ChemE already mentioned this but I think it bears repeating:

did you calculate your efficency from Jamils OG number or from the "theoretical max" based on the amount of grains?

Jamils OG assumes a certain efficiency (I think its 75%) so using his OG instead of the "theortical max" would give you a whacky number like this.

hope this helps.
 
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stevea1210

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The most important part is not a high efficiency but consistently hitting your target OG.
While my normal efficiency was nothing spectacular (71%), it was pretty consistent for me, which I liked. This out of the ordinary number has definitely skewed this brew. I decided not to dilute it, and just ride it out as is. If I had to choose between a lower consistent efficiency, and a higher but unpredictable one, I''d take the lower.


It hasn't been mentioned yet, but I think you took your preboil gravity sample out of the kettle when it was still somewhat stratified. So many extract noobs have the same problem measuring OG when they add their topoff water and don't stir it in well.
I don't blame you at all for thinking that, as I've seen many posts on these forums that were probably that. I am conscious of that when I add my last runnings and ensure I stir very well prior to drawing the sample. I start heating my wort after my first sparge round. When I add the rest following the second sparge, I ensure I stir very well to stabilize the temp in the kettle, and to try to ensure the wort is well mixed prior to drawing my sample.

I have no way to prove it, but knowing I followed that procedure, I don't think that is the case this time.


did you calculate your efficency from Jamils OG number or from the "theoretical max" based on the amount of grains?
When I enter a recipe into beer smith, I leave the efficiency at my brewhouse. I than scale the recipe to get the OG in beersmith to match the recipe I'm going off of. Following that I scale the recipe to my efficienct to determine my final grain bill.

To calculate the my efficiency I use beersmith. Due to the strangeness of the numbers in this case, I followed that up with a manual calculation based on PPG listed in how to brew.

I'm not sure if that answers your question or not. If not, please clarify, and I'll re post.
 

gabeweisz

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It could be that the malt you used had more starch than usual - IE higher PPG - than either the estimates in Beersmith and the estimates in How to Brew.
 

broadbill

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hey again steve;

can you post the recipe and your manual calculations and maybe the beersmith printout that gave you the 104%? It might help...
 

broadbill

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yup, you did and I agree with you that there was a screw up with the pre-boil measurements. It just seems that this thread is going round and round with no conclusion when your explanation seems like the most likely answer.

I'm not sure Steve got his answer (or the one he was looking for anyway) but I'm not sure there is much more to add here.:mug:
 
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stevea1210

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The recipe that cheme postd was what I used except the amounts on the crystal 60 and 120 were reversed. It was .75 of 60 and .5 of 120.

It is one of Jamils recipes available here

hey again steve;

can you post the recipe and your manual calculations and maybe the beersmith printout that gave you the 104%? It might help...
the manual calcs follow what Cheme posted. I'm not sure how to print out an efficiency report from beersmith. If someone knows how, I'll be glad to post it.

yup, you did and I agree with you that there was a screw up with the pre-boil measurements. It just seems that this thread is going round and round with no conclusion when your explanation seems like the most likely answer.

I'm not sure Steve got his answer (or the one he was looking for anyway) but I'm not sure there is much more to add here.:mug:
I think the two most likely scenarios are a screw up in the pre-boil measurements, or the scenario of a slight discepency in multiple things adding up to a large difference.

I don't think it is possible to determine with certainty what the definitive cause was. Since the brewday went wellm and didn't have any "oh ****" moments, nothing stuck out as an immdiate gotcha. I do appreciate all the help everyone has given in this thread. I've definitely got some good ideas out of it. Hopefully I'll get to brew again on Sunday, and can compare results.
 

ChemE

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The recipe that cheme postd was what I used except the amounts on the crystal 60 and 120 were reversed. It was .75 of 60 and .5 of 120...
Oops! I fixed my post on the first page to reflect the correct recipe. We found another 0.1% efficiency! Hehe, my guess is a measurement error in boiler as well.
 
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