Abv ?

[bub307]

When moving over to second fermentor and if you top of with a wine how can you get the correct ABV?

 

[Elmer]

When moving over to second fermentor and if you top of with a wine how can you get the correct ABV?

When you indicate "second fermentor" do you mean that fermentation has not completed and you are somewhere between .996 and 1.010?

If you have not finished fermenting there is no need to top up a carboy.

You top up once fermentation has completed and when you begin bulk ageing.

And even when you do top up, chances are you will be using a similar wine, which is somewhere between 11% and 13.5%.
I would think that the amount you use would not be enough to have a significant impact on your wine.

if you have just about 6 gallons of ABV 12% red and top up with a an entire bottle of 13.5% red, how much difference would it really make?

I am not a math guy so I can not tell you for certain, but I would guess, not that much!

 

[sour_grapes]

In Elmer's example, the resultant wine would be 12.065%.

 

[sour_grapes]

I guess I did not answer the question of the OP. Let Vol1 be the volume of the base wine, and Vol2 be the volume of the top-up wine. Similarly, ABV1 is the ABV of the base, ABV2 is the ABV of the top up, and ABV(blend) is the resultant ABV of the mix that we are trying to find.

Then ABV(blend) = (ABV1 * Vol1 + ABV2 * Vol2)/(Vol1 + Vol2) .

 

[richmke]

Pi/3=1 for small values if Pi and large values of 3.

ABV from SG is an estimate. When you top up an estimate with something close in value, you still end up with an estimate.

 

[bkisel]

Are you trying to adjust the ABV while topping off because you feel you didn't hit the "correct" or intend ABV?

 

[seth8530]

I guess I did not answer the question of the OP. Let Vol1 be the volume of the base wine, and Vol2 be the volume of the top-up wine. Similarly, ABV1 is the ABV of the base, ABV2 is the ABV of the top up, and ABV(blend) is the resultant ABV of the mix that we are trying to find.

Then ABV(blend) = (ABV1 * Vol1 + ABV2 * Vol2)/(Vol1 + Vol2) .

Yup, thats the way I would do it.

As to others, yes it is just an estimate, but generaly it is good practice to try and keep your estimates as accurate as reasonably possible. As was seen, the difference from topping off with one bottle's worth is not so much.. But, if you need to do some serious topping off or you use water or something it does make a difference.