Could my efficiency be that high?

[Hillsboro]

So I'm just in the first 10 minutes of my first all grain boil and I'm calculating my brewhouse efficiency. Details below:

6 lbs - English marris otter
2 lbs - flaked barley
1 lb - roasted barley
Pre-boil volume: 6.25 gal
Pre-boil gravity: 1.045

According to a couple web calculators, I'm getting around 86%. Is that possible? Or maybe a better question; is that likely? I hit all of my temp targets except my dough in temp where I was about 1 deg off at the start and after 60 minutes I dropped 5 deg.

Maybe I'm doing something wrong - maybe I'm not - any ideas?

 

[CA_Mouse]

Mash efficiency is only part of brewhouse efficiency. After your boil off and cooling loses, your brewhouse efficiency will be more accurate. I have seen as high as 90% mash efficiency, only to have my boil off ruin what I thought was great brewhouse efficiency.

 

[stpug]

Yes, definitely possible and highly likely. As long are you're measuring your volume very accurately and your gravity reading is correct, then that is what you're getting.

You'll definitely want to figure out how to keep your system from losing 5 degrees over an hour. I found I'd get overattenuated beers with large temperature drops like that (i.e. the beers would end drier and lower FG than expected - kind of unbalanced the beers).

Edit:
Ahhh, yes.... what CA_mouse says! You are providing a mash efficiency not brewhouse. Brewhouse will typically be less - but not always.

 

[Hillsboro]

Yes, definitely possible and highly likely. As long are you're measuring your volume very accurately and your gravity reading is correct, then that is what you're getting.

You'll definitely want to figure out how to keep your system from losing 5 degrees over an hour. I found I'd get overattenuated beers with large temperature drops like that (i.e. the beers would end drier and lower FG than expected - kind of unbalanced the beers).

Edit:
Ahhh, yes.... what CA_mouse says! You are providing a mash efficiency not brewhouse. Brewhouse will typically be less - but not always.

Okay thanks guys. So I ended up with 5 gallons and an OG of 1.050. According to http://www.brewersfriend.com/brewhouse-efficiency/ I'm getting 76.92% efficiency. Sounds pretty good for my first all grain, right?

 

[EarlyAmateurZymurgist]

Okay thanks guys. So I ended up with 5 gallons and an OG of 1.050. According to http://www.brewersfriend.com/brewhouse-efficiency/ I'm getting 76.92% efficiency. Sounds pretty good for my first all grain, right?

That's roughly 28 gravity points per pound per gallon for the batch, which is a perfectly acceptable extraction rate for an experienced all-grain brewer. If you maintain that extraction rate, you can determine the number of pounds of grain per gallon that you need to hit a target original gravity using the formula shown below.

(O.G. - 1.0) x 1,000 / 28

Using 1.050 as a target gravity yields:

(1.050 - 1.0) x 1,000 / 28 ~= 1.8 pounds of grain per gallon of wort


Using 1.060 as a target gravity yields:

(1.060 - 1.0) x 1,000 / 28 ~= 2.14 pounds of grain per gallon of wort