Question re. Final alcohol % and bottle carbonating

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jeanzanita

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Hi,

I've been wondering about how to determine the actual alcohol % of my final cider after back-sweetening with apple juice (to 1.005 S.G), allowing it to carbonate, and then pasteurizing.

I do the usual O.G. minus S.G. to determine the final alcohol %; but it struck me that by the addition of the apple juice and then a bit more fermentation, the final S.G. might end up a bit higher after all; since the fermentation process in the bottle is not allowed to complete.

Can anyone out there enlighten me? o_O
 

RPh_Guy

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If you use the same juice for both primary and backsweetening, just measure the FG (final gravity) after pasteurization and use that with your OG to calculate ABV. Degas the sample.

FYI
SG = specific gravity. Both OG (original gravity) and FG are SG measurements.
 

Chalkyt

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I do pretty much the same thing. I have found that I aim for my ciders to stabilise around 1.002 (using something like SO4) then I add enough original or FAJC to bring it up by 0.002 or 0.003 for carbonating (expecting it to finish again back at 1.002). So, starting at a typical OG of 1.050, I get about 6.3%ABV, then by adding another SG 0.002 for carbonation I expect that to generate another 0.3%ABV making 6.6% overall. If you pasteurise then it might be a bit less. I find that carbonating SG 0.002 worth of sugar is just about right for me.

At least that is my theory and I am not sure if anyone cares if my cider is 6% or 7% as long as it is yummy!
 

RPh_Guy

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So, starting at a typical OG of 1.050, I get about 6.3%ABV, then by adding another SG 0.002 for carbonation I expect that to generate another 0.3%ABV making 6.6% overall.
If you add the same juice, it doesn't change the ABV if you use the post-pasteurization FG.

FAJC will change the ABV, so you'll need to do a blending calculation to determine the effective OG and measure post-pasteurization FG to calculate ABV.
 
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jeanzanita

jeanzanita

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If you use the same juice for both primary and backsweetening, just measure the FG (final gravity) after pasteurization and use that with your OG to calculate ABV. Degas the sample.

FYI
SG = specific gravity. Both OG (original gravity) and FG are SG measurements.
Thanks - that makes total sense. Will try that next time :cask:
 
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jeanzanita

jeanzanita

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I do pretty much the same thing. I have found that I aim for my ciders to stabilise around 1.002 (using something like SO4) then I add enough original or FAJC to bring it up by 0.002 or 0.003 for carbonating (expecting it to finish again back at 1.002). So, starting at a typical OG of 1.050, I get about 6.3%ABV, then by adding another SG 0.002 for carbonation I expect that to generate another 0.3%ABV making 6.6% overall. If you pasteurise then it might be a bit less. I find that carbonating SG 0.002 worth of sugar is just about right for me.

At least that is my theory and I am not sure if anyone cares if my cider is 6% or 7% as long as it is yummy!
Thanks, that helps - I also don't care as long as it is yummy, but I really had no idea how much I was changing the alcohol %, being somewhat a "green" cider maker. :mug:
 
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