Mistake in The Craft of Stone Brewing - Home Brew Forums

Register Now!
Home Brew Forums > Home Brewing Beer > General Beer Discussion > Mistake in The Craft of Stone Brewing

Reply
 
Thread Tools
Old 11-11-2011, 04:50 PM   #1
agusus
Recipes 
 
Apr 2009
Seattle, WA
Posts: 114


Hi,
So I purchased the new Stone brewery book. It's great! But there seems to be a mistake in the recipe for their 12th Anniversary Bitter Chocolate Oatmeal Stout.

The beer was 9.2% ABV (stated in the book, and on their website http://www.stonebrew.com/12th/ale/) but the recipe says OG 1.099 to FG 1.022. That would produce a 10.3% beer. That's a pretty big difference, can't be just a rounding error. Their website also says the beer was 23.5 plato, which is about 1.099.

According to BeerSmith with a 1.099 OG you'd need it to ferment down to only 1.030 to get 9.2% ABV. I'm pretty sure the beer did not have that high of an FG - it would have been super sweet.

So does anyone have any idea what might have happened? Does Stone have some magical exemption to the laws of chemistry where their beers get thinner without producing alcohol (add water to the fermenter? haha)?

I think I'm going to shoot for 1.091 to get about 9.2%.

 
Reply With Quote
Old 11-11-2011, 05:34 PM   #2
remilard
Recipes 
 
Nov 2008
Kansas City
Posts: 3,654
Liked 43 Times on 41 Posts


Quote:
Originally Posted by agusus View Post
Hi,
So I purchased the new Stone brewery book. It's great! But there seems to be a mistake in the recipe for their 12th Anniversary Bitter Chocolate Oatmeal Stout.

The beer was 9.2% ABV (stated in the book, and on their website http://www.stonebrew.com/12th/ale/) but the recipe says OG 1.099 to FG 1.022. That would produce a 10.3% beer. That's a pretty big difference, can't be just a rounding error. Their website also says the beer was 23.5 plato, which is about 1.099.

According to BeerSmith with a 1.099 OG you'd need it to ferment down to only 1.030 to get 9.2% ABV. I'm pretty sure the beer did not have that high of an FG - it would have been super sweet.

So does anyone have any idea what might have happened? Does Stone have some magical exemption to the laws of chemistry where their beers get thinner without producing alcohol (add water to the fermenter? haha)?

I think I'm going to shoot for 1.091 to get about 9.2%.
Alcohol production is not a function of the difference in beginning extract and apparent residual extract. Beersmith's estimate is wrong, Stone is right.

 
Reply With Quote
Old 11-11-2011, 05:41 PM   #3
xjmox14x
Recipes 
 
Aug 2011
Pasadena, MD
Posts: 461
Liked 76 Times on 45 Posts


Quote:
Originally Posted by remilard View Post
Alcohol production is not a function of the difference in beginning extract and apparent residual extract. Beersmith's estimate is wrong, Stone is right.
Would you care to elaborate on this statement?

EDIT: upon further research, realbeer has the following equation: real extract = 0.1808 * original extract + 0.8192 * apparent extract

Being that there is an equation that can obtain real extract, does Beersmith not have a setting that allows for this? Do the typical equations used by homebrewers to determine ABV account for this discrepancy?

 
Reply With Quote
Old 11-11-2011, 07:02 PM   #4
agusus
Recipes 
 
Apr 2009
Seattle, WA
Posts: 114

Quote:
Originally Posted by remilard View Post
Alcohol production is not a function of the difference in beginning extract and apparent residual extract. Beersmith's estimate is wrong, Stone is right.
But it is mostly a function of the change in original density to final density isn't it? My impression was that ABV calculated from OG/FG might have say a 1-5% deviation from a lab test of alcohol level, but I wouldn't expect it to be 10% (error deviation from actual) like it is in this example.

This calculator - http://pint.com.au/calculators/alcohol/ - agrees with the BeerSmith estimate, and they use a variable 'f' factor (it scales as OG increases).

If you're really saying that OG/FG estimation can't approximate ABV within 5% of actual, then is there any way to do it based on ingredients list? Otherwise it sounds like a laboratory alcohol test is the only way to get within 10% accuracy?

What other chemicals contribute to decreasing a liquid's density without being a form of alcohol? Proteins increase liquid density I believe, so that's out. Polyphenols (phenolics) and esters might, but I wouldn't think those are present in high enough volume to significantly affect measured density. Hop oils probably have a lower density than wort too, but those are present in extremely tiny proportions compared to the other wort components.

 
Reply With Quote
Old 11-12-2011, 01:53 AM   #5
vespoli
Recipes 
 
Dec 2010
blah, VA
Posts: 29

Apparent vs. real extract is another big player. Hydrometers are great tools, but they are not anything compared to a digital density meter, refractometer or GC.

 
Reply With Quote
Old 11-12-2011, 04:54 AM   #6
FloatinAway
Recipes 
 
May 2011
Chino Hills, CA
Posts: 55
Liked 4 Times on 4 Posts


Edited due to stupid post

My bad

 
Reply With Quote
Old 11-12-2011, 01:23 PM   #7
r8rphan
Recipes 
 
Dec 2010
Shingletown, CA
Posts: 1,949
Liked 41 Times on 36 Posts


Where'd you get this book?

Sounds like something I want... Didn't know I wanted it, but now I do...
__________________
"DOH!"
Homer Simpson


"Beer is living proof that God loves us, and wants us to be happy."
(possibly said by) Ben Franklin (maybe)


Quote:
Originally Posted by arturo7 View Post
Damn, where's my arm?.

"You can pick your nose, and you can pick your friends... but you can't pick your friends nose!"
George Carlin

 
Reply With Quote
Old 11-12-2011, 04:25 PM   #8
agusus
Recipes 
 
Apr 2009
Seattle, WA
Posts: 114

http://www.amazon.com/Craft-Stone-Br...dp/1607740559/

For big fans of Stone it's a must have. Makes a good coffee table book too. (though I still recommend reading parts of it - the history of how they got started is pretty interesting).

 
Reply With Quote
Old 11-14-2011, 03:56 AM   #9
EricCSU
Recipes 
 
Jun 2008
Austin, TX
Posts: 1,168
Liked 62 Times on 32 Posts


Is there a discrepancy with the rest of the recipes or just that one? You should email Greg if there are errors. I bet he would want to know about it.

Eric
__________________
Kegged: Belgian Dark Strong (8.9%abv)

Fermenting: Arrogant Bastard Clone, BCS Dry stout

Planned: Rye IPA, ESB, Oatmeal Pale Ale, Rye Amber

Can You Brew It Recipe Database
Convert an all grain recipe to extract
Hop Substitution Chart

 
Reply With Quote
Old 11-14-2011, 07:51 AM   #10
FatherJack
Recipes 
 
Sep 2010
Posts: 500
Liked 15 Times on 7 Posts


I'm getting that book.
__________________
Primary: Beer
Bottled: Beer
Future Brews: Beer

 
Reply With Quote


Reply
Thread Tools


Similar Threads
Thread Thread Starter Forum Replies Last Post
Craft Brewing Article on CBC.ca birvine General Beer Discussion 0 10-25-2011 11:43 AM
First it was the transistor radio, now craft brewing..... rayg General Beer Discussion 2 06-20-2011 05:16 PM
Craft Brewing on TODAY show video hatfieldenator General Beer Discussion 7 10-31-2010 09:47 AM
Craft Brewing on NPR jklotz General Beer Discussion 2 11-29-2008 11:02 PM
Vegas Craft Brewing jaymack General Beer Discussion 3 03-31-2007 03:59 AM


Forum Jump