Efficiencies over 100%

[jeeppilot]

Hey all,

New guy to the forum, working on my 5th all-grain batch. I'm brewing a brown ale and trying to figure out what is going on with my efficiencies. I checked and rechecked my math, my inputs and everything else and it all checks out. I double checked the calibration of my hydrometer and even had two pairs of eyes on the reading.

My OG is supposed to be 1.054. The recipe determined pre-boil gravity should have been 1.044 and the actual pre-boil is 1.056. That puts my conversion efficiency at 136% and my pre-boil efficiency is 96%.

How do I have a conversion efficiency over 100%???? Am I missing something obvious? Thanks in advance!

 

[kh54s10]

I would say something is off. Either you used too much malt, or you didn't collect nearly enough wort compared to the recipe.....

 

[pricelessbrewing]

One of three things happened.

Your volumes are incorrect (entered 5 but actually 4.5-)
you used more grain than entered into calculator.
You didn't measure og at calibrated temp (68/70F)

You need three things for an efficiency calculation: gravity, recipe, and volume. If your volume is unknown, or not measured accurately ( and adjust for temperature) then you could easily be off by 5-10%.

By temperature I mean that comparing 5.75 gallons at boil is actually only 5.5G once cooled, and you should be using the volume at room temp.

 

[jeeppilot]

I use a brewing software that is doing these calculations for me and of what has been listed so far, I actually had my wort at 60F which is the exact calibrated temp for the hydrometer. The volume inputs have a temperature correction factor that adjusts for the volume changes with temperature. So that leaves me with a higher grain input than expected. I went to my local HBS and had them measure everything out, so it is possible that something was off there.

Thanks for the thoughts so far! Anything else?

 

[55x11]

Hey all,

New guy to the forum, working on my 5th all-grain batch. I'm brewing a brown ale and trying to figure out what is going on with my efficiencies. I checked and rechecked my math, my inputs and everything else and it all checks out. I double checked the calibration of my hydrometer and even had two pairs of eyes on the reading.

My OG is supposed to be 1.054. The recipe determined pre-boil gravity should have been 1.044 and the actual pre-boil is 1.056. That puts my conversion efficiency at 136% and my pre-boil efficiency is 96%.

How do I have a conversion efficiency over 100%???? Am I missing something obvious? Thanks in advance!

If you post recipe (your grain bill) and measured water volumes (pre-boil, post-boil), it may be possible to figure out where you are wrong. I see people get strange numbers (close to 100% or even above) because of wrong volume measurements, or grain weight calculations, or gravity errors (temperature corrections, inhomogeneous mixtures etc.).

If you use the software, you need to input the volumes - did you measure them carefully and entered them in - or just using some defaults? For example, if your volume is 5 Gallons but software has 6.5 Gallons as a default, that's about 30% error.
Also, predicted 1.044 pre-boil gravity is usually/probably based on some default efficiency, like 70% or so. The fact that you exceeded it by about a quarter (25%, not 36%), doesn't mean your efficiency is 136%, not even 125%, it would be 25% greater than 0.7, which would be 87% in this case.

 

[Qhrumphf]

Are you using BeerSmith? And how is your equipment configured vs. your actual process? BeerSmith is very powerful when the equipment is right (and presumably other software programs as well), but you need the equipment to be right. If you have it set for 0.5 gallons loss to the chiller and trub, and you use an immersion chiller and dump it all in the fermenter (or otherwise don't' factor those losses into whatever you consider batch size), what you're calling a 5 gallon batch, and what BeerSmith (or other program) is calculating as a 5 gallon batch, is actually a 5.5 gallon batch post-boil (that BeerSmith would then call a 5 gallon batch based on what makes it to the fermenter), with a grain bill factored as such. And since you're potentially basing your 5 gallon batch on the grainbill for something in reality larger, BeerSmith (or other program) is getting your numbers wrong.

It's the difference between mash efficiency and brewhouse efficiency.

As far as I'm aware, the only stat in brewing that can exceed 100% is apparent attenuation (where the FG drops <1.000, and that is EXTREMELY rare for beers outside of sours and potentially a few Saisons, and even then it's not common, although very common with wine/mead/cider).

 

[jeeppilot]

Also, predicted 1.044 pre-boil gravity is usually/probably based on some default efficiency, like 70% or so. The fact that you exceeded it by about a quarter (25%, not 36%), doesn't mean your efficiency is 136%, not even 125%, it would be 25% greater than 0.7, which would be 87% in this case.

This makes sense and my software is set right now for 70% efficiency!

My grain bill is as follows:

6 lb United Kingdom - Maris Otter Pale 58.5%
3 lb German - Vienna 29.3%
0.75 lb American - Caramel / Crystal 80L 7.3%
0.5 lb American - Chocolate 4.9%
10.25 lb Total

I mashed with a total of 33.5 qts water and 26 qts went into the kettle pre-boil. My gravity was 1.056 at 60F, which was the exact temp it is calibrated for.

***UPDATE***

Finished my brew day and the final gravity and volume was 1.062 with approx 5 gal... i filled it to where it starts to narrow in the glass carboy. Thats a brewhouse efficiency of 82%. That is a number I can deal that seems reasonable and I can work with!

I guess I need to consider setting my default efficiency higher.

 

[55x11]

Well the mystery still persists. Some of the measurements must be wrong. For example, you reduced 26 quarts or 6.5 gallons down to 5 gallons. That's 30% change or so. But your gravity went up only 10% or so. Doesn't make sense. Don't take it the wrong way. I just think that many of us have 10% uncertainty in our measurements and errors from multiple measurements can add up randomly, resulting in unreasonably high or low efficiency estimates. As much as we like to obsess about efficiency I never heard my neighbors spitting out my beer because they are only 5.5% ABV instead of 6%.

 

[Crucial-BBQ]

You can never have more than 100%... ...of anything.

You can increase something by more than 100% but the end result of the new whole would still be at 100%.

If you have $100 then you have 100% of $100. If you checked your pocket five minutes later and found that you now have $136, well, even though you could say you now have 136% of $100 in reality makes no sense to describe that $136 as 136% unless in terms of describing an increasing amount as once you get to $136 that $136 is now at 100% of its total.

In short, you could describe your efficiency as having increased by 136% but you cannot describe your efficiency as being 136%.

 

[Biscuits]

I am a little thrown off by the boil off volume too...actually, even the sparge volume is kind of odd. You started with over 8 gallons of water for 10.25 pounds of grain and since you say you mashed with the full volume, I am assuming this was a BIAB set up...did you not let the bag drain back into the kettle? Even so boiling off 1.5 gallons in a 60 minute boil (i assume) is a lot.

At any rate, with your grain bill the way it is and you volume of 5 gallons total after boil...I put you @ 83%...which is very good. At the end of the day, if you hit your OG and got the right volume in the fermenter, it is a success...and if there were any issues with your volumes, they will more than likely become apparent in future brews.

 

[jeeppilot]

You can never have more than 100%... ...of anything.

You can increase something by more than 100% but the end result of the new whole would still be at 100%.

If you have $100 then you have 100% of $100. If you checked your pocket five minutes later and found that you now have $136, well, even though you could say you now have 136% of $100 in reality makes no sense to describe that $136 as 136% unless in terms of describing an increasing amount as once you get to $136 that $136 is now at 100% of its total.

In short, you could describe your efficiency as having increased by 136% but you cannot describe your efficiency as being 136%.

The mathematics involved here is not the issue. I understand that part. The brewing software spit out the 136% number, and wasn't something I calculated. WHY the software spit out a number that is not only unreasonable, but impossible is the issue. Since my final numbers turned out reasonable, I must assume that, as is frequently the case, garbage in = garbage out. I just can't see where that garbage in is.

As 55x11 pointed out, the 136% efficiency number may really be predicated on the 70% efficiency I set as a default. While that may or may not be absolutely correct, it is a way better answer anything I can come up with, or an impossible number.

Dialing in my equipment profile continues to be my nemesis, and I seem to do better not paying attention to the numbers generated by the software and going with "what I know". One day perhaps I'll figure out where I'm goofing up the profile and my operation to match that profile. Then I'll gain greater consistency, which is really what I'm shooting for at this time. Until then, my final numbers turned out and I have a delicious looking a smelling beer that is fermenting vigorously and has a higher alcohol content that I was shooting for. THAT is something I will likely never complain about.

 

[Gavin C]

.deleted
misread

Sounds like your hydrometer readings are sound

Volume precision is key to solving the GIGO issue I reckon.

This may be useful