Weird efficiency! Please help!

[timschram]

I have been brewing for a good while now (two or so years) and have at least 20 all grain brews under my belt, albeit with my brother. I just brewed my second solo batch, a French saison, and hit 90% efficiency.

My brother and I routinely had efficiencies of 75-80%, but 90% seems ludicrous. Grain bill as follows:

8# Belgian Pilsner
2# Belgian Munich
.5# caramel 60

I forgot to get a pre boil gravity, but my post boil gravity, after transfer to ale pail before yeast, was 1.064.

Am I missing something? Please shed some light!!!!

 

[beskone]

It's hard to tell efficiency without a pre boil gravity. You could have boiled off more than you were expecting which threw the numbers off.

I have been brewing for a good while now (two or so years) and have at least 20 all grain brews under my belt, albeit with my brother. I just brewed my second solo batch, a French saison, and hit 90% efficiency.

My brother and I routinely had efficiencies of 75-80%, but 90% seems ludicrous. Grain bill as follows:

8# Belgian Pilsner
2# Belgian Munich
.5# caramel 60

I forgot to get a pre boil gravity, but my post boil gravity, after transfer to ale pail before yeast, was 1.064.

Am I missing something? Please shed some light!!!!

 

[doug293cz]

You need accurate SG and volume measurements in order to calculate accurate efficiencies. Volume measurements should also be corrected to the calibration temp of the hydrometer. You don't give a post-boil volume, so it's impossible to check your efficiency. If you didn't measure your post-boil volume, and just assumed it was what your recipe predicted, then that could throw you way off. If your boil off was higher then expected, that would increase your OG, and decrease your volume. If you used an assumed volume that was to high, that would inflate your efficiency.

Brew on

 

[Gavin C]

Am I missing something?

Yes. Volume in the fermentor.

Calculating brewhouse efficiency requires three pieces of info. You're missing one.

• The estimated potential gravity points available in the grain-bill
• OG
• Volume in the FV

Edit: Should have read down. Already answered. Sorry bout that.

 

[55x11]

You need accurate SG and volume measurements in order to calculate accurate efficiencies. Volume measurements should also be corrected to the calibration temp of the hydrometer. You don't give a post-boil volume, so it's impossible to check your efficiency. If you didn't measure your post-boil volume, and just assumed it was what your recipe predicted, then that could throw you way off. If your boil off was higher then expected, that would increase your OG, and decrease your volume. If you used an assumed volume that was to high, that would inflate your efficiency.

Brew on

Ditto. i suspect your calculation you are using pre-boil volume but post-boil SG, which may give you 90%.

If you boiled it down to 5G, for example, your efficiency would end up about 67%.
If you boiled down to 6G and measured 1.064, it's 80.3%.

finally, stating the obvious - did you add any sugar during the boil (many saisons call for that)? This should be included in calculation, of course.

 

[timschram]

My volume was about 5.5 gallons, maybe a bit less.

 

[hottpeper13]

That same thing happened to me and it turned out the base grain had a higher GU per pound,but it only went from 80 to 86%.

 

[Gavin C]

That same thing happened to me and it turned out the base grain had a higher GU per pound,but it only went from 80 to 86%.

All things being equal that will result in a higher amount of sugars in the FV and a higher OG but not a higher brewhouse efficiency if the correct figures are entered in the grain-bill's characteristics to reflect the higher PPG numbers.

 

[55x11]

My volume was about 5.5 gallons, maybe a bit less.

Then I get about 74% mash efficiency which is pretty reasonable.

 

[doug293cz]

Then I get about 74% mash efficiency which is pretty reasonable.

Even at 5.5 gal post-boil & 1.064, I still get about 93% efficiency, which seems unreasonably high.

Grain pts = (8 + 2 + 0.5) * 36 = 378
Wort pts = 5.5 * 64 = 352
352 / 378 = 0.93 => 93%​

Brew on

 

[timschram]

Any idea what legitimate breweries get efficiency wise? And what is about normal for all you guys?

 

[Gavin C]

I reckon commercial breweries would be knocking on the door of ~99% conversion efficiency, lautering efficiency ~95% if they centrifuge or squeeze the grain bed in some fashion.

Their mash efficiency has got to be well over 90%. (~95%)

Hop absorption and break material is unavoidable. I'm guessing they don't chuck it all into the fermentor and are seeing ~5% in looses to break, hops absorption and dead spaces (negligibly small).

Coming in at ~90% brewhouse efficiency.

This is all purely guestimation on my part based on the likely unavoidable minimums in volume losses.

I tailor recipes to 80% BH efficiency. (that will go up or down a touch in-line with the planned OG)

 

[55x11]

Even at 5.5 gal post-boil & 1.064, I still get about 93% efficiency, which seems unreasonably high.

Grain pts = (8 + 2 + 0.5) * 36 = 378
Wort pts = 5.5 * 64 = 352
352 / 378 = 0.93 => 93%​

Brew on

this sounds about right, I must have made a mistake somewhere.
93% is quite high. I get 75-85%, even though mostly it's 75-80% range. I think I had a 70-72 once.

So no sugars and you are pretty sure about weights, volumes and SG measurements? If so, kudos!