Confused how to calculate abv after 2nd fermentation

[Soulshifted]

Hello!

I'm getting ready to make a cherry cyser, and I'm a bit stumped on something.

So, after the primary fermentation, I intend to add Oregon Cherry Puree to the secondary. How do I know how to calculate the change in gravity after doing so? So like, I'll have the original gravity, and the gravity after primary, then X Unknown Gravity after adding the cherry, then the final gravity at the end. How do I determine what the overall abv is?

Thanks for anyone who can help!
~ River

 

[VikeMan]

To calculate the effective combined OG, predict ABV, etc., you need to know (or estimate) the base OG and volume, and the volume and OG of the addition. I wrote an article about this in the May-June 2021 issue of BYO.

https://byo.com/article/ciphering-fruit-beers/
If you have that issue (or an online subscription), the formulae are there. Or you can download the FruitCalc spreadsheet that does the math and comes loaded with the data for many fruit addition types (including cherry puree).

FruitCalc Download

 

[Soulshifted]

Thank you!

To calculate the effective combined OG, predict ABV, etc., you need to know (or estimate) the base OG and volume, and the volume and OG of the addition. I wrote an article about this in the May-June 2021 issue of BYO.

https://byo.com/article/ciphering-fruit-beers/
If you have that issue (or an online subscription), the formulae are there. Or you can download the FruitCalc spreadsheet that does the math and comes loaded with the data for many fruit addition types (including cherry puree).

FruitCalc Download