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Brego Brew
05-13-2011, 05:48 PM
I know I remember seeing a thread about this but I can't find it, and I can't seem to get the Calculator to tell me what I want.

I'm making a brew and let's say it's five percent after fermenting dry, now I rack that onto 10 lbs. crushed red raspberries. That sits for about a week to extract the flavor but the fermentation has started back up on these Raspberries. How do I find out what my New ABV is?

Thanks!

PitBull
05-13-2011, 07:46 PM
I know I remember seeing a thread about this but I can't find it, and I can't seem to get the Calculator to tell me what I want.

I'm making a brew and let's say it's five percent after fermenting dry, now I rack that onto 10 lbs. crushed red raspberries. That sits for about a week to extract the flavor but the fermentation has started back up on these Raspberries. How do I find out what my New ABV is?

Thanks!
Use the calculator and assume it was all added at the beginning. If all the fermentables are consumed by the yeast, the calculator should provide a reasonable estimation. For ABV calculations, it really should not matter at which stage the berries are added.

AToE
05-13-2011, 07:48 PM
The question I have about the calculator in regards to fruit is whether it's factoring their juice into the total volume (this is my guess) or adding it on top of your stated volume. Figuring that out would be important for using the calculator for this kind of thing.

akueck
05-14-2011, 12:07 AM
My understanding is that the volume you enter in the calculator includes the volume of all additions, including the fruit. The calculator is adding up the sugar from each source and dividing it into the total volume. Fruit will add both water and sugar, but also solids. Ideally you'd add the volume of the non-solids part to the calculator, though that may be difficult to figure out. In reality the solids will sequester some of the liquid too, but now we're splitting hairs.

Gespacho
05-14-2011, 06:29 AM
Correct me if I'm wrong, but would a Vin-o-meter give an accurate reading of the ABV after fermentation has stopped? They are pretty cheap at the home brew store.

TheAlchemist
05-14-2011, 10:10 AM
With Buckwheat Pancakes I'm gradually adding more maple syrup over time. Not sure how the calculator would work with a project like this. Is there any such thing as an alcohol measuring device so I could just take a reading at the end?

akueck
05-14-2011, 03:44 PM
Correct me if I'm wrong, but would a Vin-o-meter give an accurate reading of the ABV after fermentation has stopped? They are pretty cheap at the home brew store.

I think those assume zero residual sugar. If you have a totally dry mead, it should work.

Chevette Girl
05-15-2011, 05:47 PM
With Buckwheat Pancakes I'm gradually adding more maple syrup over time. Not sure how the calculator would work with a project like this. Is there any such thing as an alcohol measuring device so I could just take a reading at the end?

You can do a boil test of your finished product where you take a measured volume of finished wine and boil it till you're sure there's no alcohol left and then reconstitute to your starting volume with water and figure out the percent ethanol by the difference in SG... oh, it's got a name, what the heck is it... first my eyes, then my knees, now my nouns... I'll go look it up again.

<edit> Called Spirit Indication, here's how (http://www.gotmead.com/forum/showthread.php?t=17312)...

Gespacho
05-16-2011, 11:01 AM
I think those assume zero residual sugar. If you have a totally dry mead, it should work.

It would have been nice if that was in the instructions for the damn thing. :rolleyes: Oh well, I least I didn't buy one.

Medsen Fey
05-16-2011, 11:12 AM
Correct me if I'm wrong, but would a Vin-o-meter give an accurate reading of the ABV after fermentation has stopped? They are pretty cheap at the home brew store.


:rolleyes: Oh well, I least I didn't buy one.

They can be quite inaccurate even with a dry batch. As far as I'm concerned they are worthless so it is good you saved the money.

Brego Brew, in addition to the spirit indication method, you can also combine hydrometer and refractometer reading to get a measurement. Sometimes the numbers can be a little "squirrelly" but usually I find it to be pretty close. Vinocalc has a nice calculator to do the job - that's about as close to a direct alcohol measuring machine as you're going to find.

havoc64
05-16-2011, 03:22 PM
I have wondered this too. I have used D47 on all my batches and they seem to end around 14.20%. If I add the fruit to the secondary, I would venture a guess that the yeast will start back up and go again to around 14% again. Does that sound logical to anyone else? ???

Medsen Fey
05-16-2011, 04:13 PM
If I add the fruit to the secondary, I would venture a guess that the yeast will start back up and go again to around 14% again. Does that sound logical to anyone else? ???

They will if the potential alcohol is there to get to 14%. With most fruits the potential alcohol is substantially lower (unless using ripe grapes) so the ABV may be a little lower (or a lot lower if you use huge amounts of fruit).