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Old 01-18-2013, 12:33 AM   #1
LiquidLunch5211
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Is it possible to calculate ABV after beer has been carbonated if I have OG?


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Old 01-18-2013, 12:49 AM   #2
forstmeister
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Quote:
Originally Posted by LiquidLunch5211
Is it possible to calculate ABV after beer has been carbonated if I have OG?
If you have the OG and feel you can safely assume the FG then you can calculate the ABV. Most of my beers finish around 1.010 unless I am aiming higher.


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Old 01-18-2013, 12:55 AM   #3
LiquidLunch5211
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Quote:
Originally Posted by forstmeister

If you have the OG and feel you can safely assume the FG then you can calculate the ABV. Most of my beers finish around 1.010 unless I am aiming higher.
The pre boil was 1.105
OG 1.062
I measured FG at 1.035
If my calc is right it's only roughly 3.4%
I was just wondering if I could take another reading but its already carbonated
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Old 01-18-2013, 12:55 AM   #4
Swib
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I would pour a beer and let it go flat (you could help it along through agitation), then measure the gravity of the now flat beer.

Will it be perfectly accurate, not sure. Will it get you close, I would think so.

 
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Old 01-18-2013, 12:56 AM   #5
Psych
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Quote:
Originally Posted by Swib View Post
I would pour a beer and let it go flat (you could help it along through agitation), then measure the SG of the now flat beer.

Will it be perfectly accurate, not sure. Will it get you close, I would think so.
This.

Just make sure you account for temperature, if the sample is still cold then you must adjust for the difference (there's calculators out there for this) as hydrometers are set for 60f or 65f. Otherwise your reading will be out (too high, if it's below 65f).

 
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Old 01-18-2013, 12:58 AM   #6
LiquidLunch5211
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Quote:
Originally Posted by Psych

This.

Just make sure you account for temperature, if the sample is still cold then you must adjust for the difference (there's calculators out there for this) as hydrometers are set for 60f or 65f. Otherwise your reading will be out (too high, if it's below 65f).
I use a refractometer does temp make a a difference?
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Old 01-18-2013, 01:07 AM   #7
forstmeister
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Quote:
Originally Posted by LiquidLunch5211

I use a refractometer does temp make a a difference?
Refractometers do not measure fermented wort accurately. You need a hydrometer for that.
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Old 01-18-2013, 01:09 AM   #8
LiquidLunch5211
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Quote:
Originally Posted by forstmeister

Refractometers do not measure fermented wort accurately. You need a hydrometer for that.
Ok thanks is my math accurate for final ABV
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Old 01-18-2013, 01:19 AM   #9
cluckk
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Quote:
Originally Posted by LiquidLunch5211

Ok thanks is my math accurate for final ABV
It looks right.
(( (OG-FG)*105)*1.25)=ABV
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Old 01-18-2013, 01:22 AM   #10
forstmeister
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Quote:
Originally Posted by cluckk

It looks right.
(( (OG-FG)*105)*1.25)=ABV
I am so lazy. I haven't calculated abv in forever. Once I put brewing software on my phone and computer I gave up doing actual math.


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