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Old 01-11-2010, 04:48 AM   #1
Jan 2010
Silver Spring, MD
Posts: 203
Liked 8 Times on 6 Posts

Hi all,

I brewed a hybrid of a few recipes I found for an IPA and I'd like to figure out the actual ABV of the final product. The thing is the recipe called for doing the normal extract procedures on brew day, and then 2 days later, adding 1/2 lb of light brown sugar (boiling it first) directly to the fermenter.

My only gravity readings are from the OG (1.062) and the FG (1.014). Going from the text book here, with temp corrections, that says it's around 6.3% ABV. Problem is that has got to be off due to changing the gravity when I added the brown sugar, right? So is there some way to find out how much it altered things?

I found this site http://www.brewheads.com/refract-getabw.php which seemed promising. But I took a brix reading that said 6.8 and the FG of 1.014 which gave me 4%. That calculation seems kind of unrealistic though given the OG/FG readings.

If there's no way to figure it out after the fact, could someone at least tell me how to get an accurate calc in the future if I end up doing something like this? Thanks!

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Old 01-11-2010, 05:37 AM   #2
Nov 2009
Vancouver WA
Posts: 112

A rule of thumb is to add 10 points to the OG for every pound of adjunct sugar. Since you've added a 1/2 pound of brown sugar, I'd say you raised your OG by 5 points, going from 1.062 to 1.067.
Not all chemicals are bad. Without chemicals such as hydrogen and oxygen, for example, there would be no way to make water, a vital ingredient in beer.
-Dave Barry-

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Old 01-11-2010, 01:27 PM   #3
RCCOLA's Avatar
Nov 2008
Northwest Arkansas
Posts: 1,069
Liked 96 Times on 58 Posts

Here's a free homebrew calculator. Just enter all your ingredients and voila! All your questions answered.


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Old 01-11-2010, 03:46 PM   #4
david_42's Avatar
Oct 2005
Oak Grove, Oregon, USA
Posts: 25,599
Liked 158 Times on 148 Posts

After the fact, you'll need a precision scale and a water bath to boil off the alcohol.
Remember one unassailable statistic, as explained by the late, great George Carlin: "Just think of how stupid the average person is, and then realize half of them are even stupider!"

"I would like to die on Mars, just not on impact." Elon Musk

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