Determining ABV when adding fermentables to secondary

[kahlerisms]

Hi Guys

Today or tomorrow I'm moving my sweet stout to secondary and throwing it onto some cherry puree that I'm going to make up from some frozen cherries. (the recipe I'm following is in Jamil's classic styles)

I know my ABV at the moment but this will change when I add more fermentables in secondary.
I plan to bottle this one and give it away as gifts so I was really hoping to be able to calculate the ABV somehow.

Anyone got any ideas or is this a bit beyond us garage brewers?

 

[stef]

If you know the actual amount of fermentables, then just work it out as if it were added during the boil. So if you're using software, and you were (for example) adding 500g of sugar after/during ferment, you would just add it to your software as if it was during the boil. Given that you are using fruit, its slighly harder. I would suggest that it wouldnt be a huge amount though... You'd have to research the sugar content of your cherries (or the average for cherries) and add it that way.

 

[BeerNess]

I've had this dilemma myself, i think with the same recipe! I just threw an extra 0.5% on what I'd calculated from fermentation and bottling sugar. Had no complaints :beer:

 

[felten]

If you have a refractometer and a hydrometer, it is possible to take a reading of the finished beer and work out an estimate of the OG. And with that and the FG, you should be able to guesstimate the ABV.