Backsweetening's impact on ABV?

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abandonhope16

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How is ABV calculated when backsweetening? I assume that sweetening at bottling will lower the ABV. When would you take a hydrometer reading? Let's say for example that OG was 1.060 and brought to 1.000, then sweetened.
Thanks for the info.
 
I take my gravity before adding anything. You can only use gravity to check your ABV if you don't add anything in between your OG and FG readings. If you do add something that will throw off you ABV number. I can't see how sweetening will affect how much alcohol is in the mix. I guess if you sweetened by adding a gallon of simple syrup then it would change things but your not doing that, right? The non fermentable sugars you back sweeten with won't change how much alcohol is in the cider but might change your gravity reading. Man, I have had too many ciders to answer this coherently.
 
abandonhope16 said:
How is ABV calculated when backsweetening? I assume that sweetening at bottling will lower the ABV. When would you take a hydrometer reading? Let's say for example that OG was 1.060 and brought to 1.000, then sweetened.
Thanks for the info.
Click to expand...

Good question! It's all about volume...

Let's take an 'academic situation' as an example.

You ferment 5 gallons out to dryness and get an ABV of 10% for that 5 gallons. If you then backsweeten with a gallon of cider you reduce the ABV by 1/6 or 16%. Leaving you with 6 gallons of 8.4%.

:)
 
WilliamSlayer said:
Good question! It's all about volume...

Let's take an 'academic situation' as an example.

You ferment 5 gallons out to dryness and get an ABV of 10% for that 5 gallons. If you then backsweeten with a gallon of cider you reduce the ABV by 1/6 or 16%. Leaving you with 6 gallons of 8.4%.

:)
Click to expand...

That's good to know, I did a reg one gal batch of cider at first racking I added one cup chopped raspberries, 3 tbs brown sugar and about 1/2 tsp champagne yeast.
24 hrs later it was working very well. I would assume with adding the same yeast and ras. and sugar the abv should not drop ? rise. 2nd rack was carefully thru a massive
Cheese cloth filter 3rd rack after 2 weeks clear as can be, dry but very tasty, I assume the abv was near the original.
 
WilliamSlayer said:
Good question! It's all about volume...

Let's take an 'academic situation' as an example.

You ferment 5 gallons out to dryness and get an ABV of 10% for that 5 gallons. If you then backsweeten with a gallon of cider you reduce the ABV by 1/6 or 16%. Leaving you with 6 gallons of 8.4%.

:)
Click to expand...

Interesting, you are essentially proportionally diluting the ABV. With this, sweetening with frozen concentrate or sugar would have less of an impact on ABV?
 
I'm confused on something? Can't you take a reading before you pitch your yeast, Then take another reading when you rack into your bottling bucket at the end to find out exactly what you're ABV is? Then I thought you could back sweeten in your bottling bucket and then take another reading?

Example: your must starts at 1.060 and when finished (say .995), gives you an ABV of 8.63%
So Why can't you back sweeten to taste and then take another reading?
Say it goes back up to 1.012 after you back sweeten..... Wouldn't you have 6.37% ABV?
 
BadgerBrigade said:
I'm confused on something? Can't you take a reading before you pitch your yeast, Then take another reading when you rack into your bottling bucket at the end to find out exactly what you're ABV is? Then I thought you could back sweeten in your bottling bucket and then take another reading?

Example: your must starts at 1.060 and when finished (say .995), gives you an ABV of 8.63%
So Why can't you back sweeten to taste and then take another reading?
Say it goes back up to 1.012 after you back sweeten..... Wouldn't you have 6.37% ABV?
Click to expand...

Not quite, as WilliamSlayer posted, ABV post backsweetening can be calculated by dilution. Backsweetening with sugar to 1.012 will not affect the ABV as much as backsweeting with juice to 1.012 because the volume of dilution is not the same.
 
LeBreton said:
Not quite, as WilliamSlayer posted, ABV post backsweetening can be calculated by dilution. Backsweetening with sugar to 1.012 will not affect the ABV as much as backsweeting with juice to 1.012 because the volume of dilution is not the same.
Click to expand...

So say you start at 1.060 and get to .995, then you add 1/4 a gallon of juice... How would you figure this out? (I am a visual learner and pretty crappy at my math skills, Maybe you can break it down the easiest way) :)
 
It's essentially the same equation as an average:
(Volume1 X ABV1) + (Volume2 X ABV2) / (Volume1 + Volume2)

(5gal x 8.6%) + (.25 x 0.0%) / 5.25 = 8.19%
 
LeBreton said:
It's essentially the same equation as an average:
(Volume1 X ABV1) + (Volume2 X ABV2) / (Volume1 + Volume2)

(5gal x 8.6%) + (.25 x 0.0%) / 5.25 = 8.19%
Click to expand...

I knew I should've paid more attention in algebra... Lol
 
For a Aerospace machinist and jeweler this is really quite embarrassing... Lol
But I'm still having trouble?

Okay let's try new scenario maybe I can get my brain running...

Say I have 3 gallons that started at 1.060 and ended at .995, my ABV calculator says 8.63%ABV and I want to get it down to 6%, How do I figure this?

(I have a little bit of mathematic dyslexia, Throughout school teachers would try to explain a math problem to me over and over again... Once they reversed the way the equation went I would get it right away.... Try me one more time and hopefully the wheels will start turning :)
 
BadgerBrigade said:
For a Aerospace machinist and jeweler this is really quite embarrassing... Lol
But I'm still having trouble?

Okay let's try new scenario maybe I can get my brain running...

Say I have 3 gallons that started at 1.060 and ended at .995, my ABV calculator says 8.63%ABV and I want to get it down to 6%, How do I figure this?

(I have a little bit of mathematic dyslexia, Throughout school teachers would try to explain a math problem to me over and over again... Once they reversed the way the equation went I would get it right away.... Try me one more time and hopefully the wheels will start turning :)
Click to expand...

Just off the top of my head and with no equations involved...

Add one gallon.

Ok, someone double check my idiot savant math please! :)
 
I'm still having some trouble with the guys (& gals), maybe someone can break it down mathematically for me so I can see how you calculate this?


I tried to follow the conversation and figure out how to calculate the exact percentage but I'm still having trouble.
I'm also kind of a visual learner so I'm wondering if maybe I can give you the variables of my last batch and if you could walk me through the calculation process?
I asked the gentleman at my local homebrew supply shop but he was no help and couldn't figure it out.

I did a 3 gallon batch of fresh pressed apple juice and added a little bit of brown sugar.
The OG was 1.070, it stopped at .995.
I believe this put my alcohol by volume at about 10%?
About a week before bottling I added some cedar wood chips.
I made an Apple Cedar Cherry Cider and it really did taste fantastic!


At bottling time I added around a pint of concentrated apple, juice 3 ounces of dextrose in a little bit of water(to make carbonation in the bottle) and three quarters of a quart of black cherry juice.
(The black cherry juice has approximately 25 g per serving of sugar the serving sizes 8 ounces)

Just trying to figure out what the percentage is after I added the black cherry juice....
 
At a glance my guess is you are confusing yourself with sugars I think. The idea here is working out volume. The big equation took into account mixing two alcoholic beverages I believe after a skim read the thread. So think of it as what is my final alcohol content if I topped up with a litre of water after completing fermentation. You wont be doing any fermenting so all you have to worry about is working what the alcohol percentage will drop by .

So if you have (3gallon at(x) 10%) +(no alcohol in second mix) / Total volume (3+0.3125)
so (3*0.1)/3.3125 which gives 9.05%

If your second liquid added had 3% alcohol in the "no alcohol in second mix" part you would have had (.3125*.03)

Maybe Im making it worse lol.
 
waxer said:
At a glance my guess is you are confusing yourself with sugars I think. The idea here is working out volume. The big equation took into account mixing two alcoholic beverages I believe after a skim read the thread. So think of it as what is my final alcohol content if I topped up with a litre of water after completing fermentation. You wont be doing any fermenting so all you have to worry about is working what the alcohol percentage will drop by .

So if you have (3gallon at(x) 10%) +(no alcohol in second mix) / Total volume (3+0.3125)
so (3*0.1)/3.3125 which gives 9.05%

If your second liquid added had 3% alcohol in the "no alcohol in second mix" part you would have had (.3125*.03)

Maybe Im making it worse lol.
Click to expand...

No dude! That spelled it out great for me, thank you.
Sometimes I think I just need to hear (or see) it a few different ways.
:mug:
 
WilliamSlayer said:
Good question! It's all about volume...

Let's take an 'academic situation' as an example.

You ferment 5 gallons out to dryness and get an ABV of 10% for that 5 gallons. If you then backsweeten with a gallon of cider you reduce the ABV by 1/6 or 16%. Leaving you with 6 gallons of 8.4%.

:)
Click to expand...
 

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