+1 hr sparge = +20% efficiency!?

sbaclimber

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Normally I do a single batch sparge (traditional, not biab) for 30 min at ~72°C and have a brewhouse efficiency of 70-80%
Today, I let the sparge sit for 90 min and ended up with a very high OG and a brewhouse efficiency of 97%!
Is that normal? fwiw, it was only 6kg of grain and 15l of sparge H2O...
 
you mean mash efficiency probably, brew house is the whole time through fermentation to final gravity and that is possible
 
you mean mash efficiency probably, brew house is the whole time through fermentation to final gravity and that is possible
yes and no, sorry for leaving out some key info...
I do mean brewhouse, but that is assuming "normal" attenuation. ...which, no, I cannot verify until in 3-4 weeks. And changing the attenuation only changes the FG anyway.
I have never measured mash efficiency and only tweak brewhouse efficiency and attenuation in the calculator here to match up with what I measure (OG pre-fermentation, FG post-fermentation). Those two number haven't fluctuated much over the past few dozen brews, because I mostly brew more or less the same recipe and have a fairly static setup, including fermentation temp-control, so I was really surprised to see my spindle 4+°Plato over what I normally measure for an OG today!
 
well even so I've never heard of 97% brew house, you sure water and grain was correct, something doesn't sound right
 
something doesn't sound right
I agree with you there.
Will see what the spindle says in a few weeks... If the FG is "normal" and the beer doesn't blow my head off (calculated ABV is currently 8-9% relative to attenuation, should've been ~6%), then it will have been a measurement error of some sort.
 
Agreed. Something is wrong. And for it to be that wrong, I'd guess measurement error: Brewhouse of 97% assumes that you got 100% of the theoretical yield of the malt and only lost 3% of the sugars produced in your process. The spent grain holds more sugar than that! The first place I'd look is my hydrometer.
 
I’ve done exceedingly well in efficiency sometimes. I’ve wondered if the grains could have more sugar in them then the software thinks. Is that a possibility?
 
I’ve done exceedingly well in efficiency sometimes. I’ve wondered if the grains could have more sugar in them then the software thinks. Is that a possibility?
Not that much. Brewhouse is the percentage of possible sugars you get into your fermentor, implying at most 3% losses. The spent grain will hold more sugar than that, even if we assume the maximum possible extract from the grain. I think there's an error somewhere, likely in a gravity reading.
 
Gravity reading, scale error. Something.

I wasn’t referring to sugars not rinsed from the grain. I meant the maximum amount of sugar that could be obtained from the grain. It just seems reasonable to me that it could be different than what the app says it is.
 
Normally I do a single batch sparge (traditional, not biab) for 30 min at ~72°C and have a brewhouse efficiency of 70-80%
Today, I let the sparge sit for 90 min and ended up with a very high OG and a brewhouse efficiency of 97%!
Is that normal? fwiw, it was only 6kg of grain and 15l of sparge H2O...
What was your expected OG and what did you actually get? I range between mid 70’s to low 80’s fo my Brewhouse efficiency.
 
Gravity reading, scale error. Something.

I wasn’t referring to sugars not rinsed from the grain. I meant the maximum amount of sugar that could be obtained from the grain. It just seems reasonable to me that it could be different than what the app says it is.

Yes, and it may vary from batch to batch (the maltster's batches I mean, not necessarily yours!). And different maltsters may have slightly different moisture contents from their own batches, and those would even vary between maltsters. So a slight difference is to be expected. The only way to truly calculate the true efficiency with complete accuracy would be to get a malt analysis sheet with each bag of malt.

That said, it would not make a huge difference. Certainly not more than a percentage or two- and sometimes even on a malt analysis sheet, a maltster will give a range anyway, and not a specific one for each lot, like "81-83% DBFG" So even within the same maltster's specs, there is a variation. Most homebrewers don't get a malt analysis sheet for each lot, and I don't even know how many pros in smaller breweries do. It really doesn't impact efficiency that much, and often the numbers given in the software are close enough to reality to not make a difference.
 
That’s the answer I was looking for. Thanks!
 
What was your expected OG and what did you actually get? I range between mid 70’s to low 80’s fo my Brewhouse efficiency.
As I normally have ~70% brewhouse efficiency, the OG should have been 13.5-14° Plato.
...what I got was 18.7°!!

Here is the recipe: https://www.brewersfriend.com/homebrew/recipe/view/614704/2018-02-gpa-68-plan
The only not mentioned is that I boiled the first wort (~15L) and second running separately, but both for 60 min. I just split the hops between them. In other words, the IBUs are probably a bit off.
 
Gotta admit I'm curious, cause that seems perpetual motion territory.
 
I had a crazy thought today, that though unlikely, *could* explain the high OG...
What if the 15L first wort, after boiling and draining (I have a 3 tiered gravity setup) into the fermenter, ended up staying unmixed at the bottom of the fermenter, even after draining the 2nd running post-boil on top of it?
I always pull wort for my OG measurement from the spigot and never thought to stir it up a bit first...
 
I had a crazy thought today, that though unlikely, *could* explain the high OG...
What if the 15L first wort, after boiling and draining (I have a 3 tiered gravity setup) into the fermenter, ended up staying unmixed at the bottom of the fermenter, even after draining the 2nd running post-boil on top of it?
I always pull wort for my OG measurement from the spigot and never thought to stir it up a bit first...
Very much a possibility! One I'd thought of and avoid by stirring my wort before taking a gravity reading. If you had no turbulence and just ran the second runnings on top of the first, there'd be little mixing, so that could well be the source of your problem!
 
Very much a possibility! One I'd thought of and avoid by stirring my wort before taking a gravity reading. If you had no turbulence and just ran the second runnings on top of the first, there'd be little mixing, so that could well be the source of your problem!
Okay, good, then if the ABV turns out close to expected (measured by drinking enough samples of the finished beer, of course ;) ), then I will assume that is what happened. :D
 
I had a crazy thought today, that though unlikely, *could* explain the high OG...
What if the 15L first wort, after boiling and draining (I have a 3 tiered gravity setup) into the fermenter, ended up staying unmixed at the bottom of the fermenter, even after draining the 2nd running post-boil on top of it?
I always pull wort for my OG measurement from the spigot and never thought to stir it up a bit first...

A common problem with extract brewers who top of their fermenters, but never associated it with all grain. Probably because it's not common to boil first and second runnings separately. I do think you nailed it tho.
 
UPDATE!
Just measured the OG of the exact same recipe brewed exactly the same way again (only this time stirred well before measuring), and.....13.8° Plato, which is 69% brewhouse efficiency. Way more in line with what I was expecting. :D
And the previous batch doesn't blow my head off either, so all-in-all I am chalking up the high OG/efficiency to measurement error due to unmixed wort.
 

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