[Erik_Mog]

Quick question about blood orange puree.  I am going to brew the Heathenweizen (Blood Orange Hefeweizen) tomorrow.  After primary I plan to add basically 3# (49oz) of puree to to a secondary and let it go for another 7 days or longer to make sure gravity has stabilized.  I know that once it gets put on the puree, there will be some secondary fermentation due to the added sugar.  Is there any way to even estimate how much additional ABV the puree would add or is just an add it and see what happens type of thing.  Baring any huge errors on my part, the brew I am aiming for according to BrewSmith's calculations on my recipe is OG:1.049 FG:1.016 and ABV:4.3%, not accounting for the puree added in secondary.  I'm hoping that the final ABV doesn't goo up too much but it's not a big deal if it does either.

If it's any help the can of puree shows SG of 1.036-1.065.

[69franx]

If you have a refractometer, you can measure the sugar content of the puree. With that knowledge, you can do some math(not sure which/how) to add the puree's contribution to your abv. You should be able to safely assume all the sugar will be converted. Not a full answer, I know, but a path to get there if you have the tools. The manufacturer may also state the sugar content somewhere in their info on the puree if you don't have the refractometer

[brewinhard]

A lot of the puree will also be water-based, so as far as brewing is concerned, it really won't raise your OG by that much (as in probably not even .5% abv).

[Erik_Mog]

no refractometer here.  I'm not at that level yet.  According to the nutritional info on the can, there is 110g of sugar in the 49oz can of puree.  I don't really care that much if the ABV goes up, it's mainly a curiosity thing.  I'm trying to learn as much as I can about how and why things work in brewing.

[Iliff Ave]

From what others have told me, you can pretty much neglect the change in ABV from adding most fruits because you are adding volume along with the sugar so it ends up a wash.