how to reduce ABV in 1 gal batch

[GeneDaniels1963]

I had some bits and pieces laying around, so I brewed up a 1 gal batch with 1.5 lb pilsen DME, 6oz of Briess cara Pils (steeped) and a couple handfuls of raisins. Using mugwort and wormwood for bittering. The OG was higher than I was expecting, 1.093.

It has just started fermeting. I am thinking about pouring some out and adding some boiled water to bring down the gravity. Should I do that now, or wait until it has fermented? Or something else?

 

[McKnuckle]

If you must do this, do it ASAP. The further into fermentation you get, the more risk of oxidation from adding anything to the beer. If you can add the boiled/cooled water without any splashing (use a siphon, or get creative), that's best. And don't neglect the importance of matching the temperature in the fermenter. You don't want to dramatically alter the temp during an active fermentation.

 

[Snuffy]

But... why?

 

[GeneDaniels1963]

At this rate its going to be 10.5, maybe 11%. Thats a lot bigger ale than I was wanting to make

 

[VikeMan]

Did you boil this down to less than a gallon? Otherwise, 1.5 pounds of DME and 6 ounces of carapils wouldn't get you more than ~1.076. And that's assuming 100% steeping efficiency from the carapils (which can't happen). I'm ignoring the raisins, assuming you didn't mince/shred the raisins and include them in the boil. If you did mince/shred and boil the raisons, I guess that might do it. I don't know the weight of a couple of your handfuls.

At this rate its going to be 10.5, maybe 11%. Thats a lot bigger ale than I was wanting to make

What kind of attenuation are you expecting, and why? Assuming the total effective OG of 1.093 is correct, you'd need about 86% apparent attenuation to reach 10.5% ABV and about 90% apparent attenuation to reach 11% ABV. This doesn't seem likely, unless you're using a very attenuation yeast strain. What did you use?

 

[GeneDaniels1963]

I chopped and boiled the raisins. Unless my refractometer is off, it measured 22 Brix. That's about 1.093. So depending on which chart you use for potential ABV, that will give me between 10%+ ABV at 80% attenuation.

Also, I may have ended up with a touch less than 1 gal volume. That, plus the boost from the raisins probably accounts for the higher than expected OG.

 

[VikeMan]

That's about 1.093. So depending on which chart you use for potential ABV, that will give me between 10%+ ABV at 80% attenuation.

1.093 at 80% AA would yield a final gravity of 1.0186, at about 9.77% ABV. What chart are you looking at that shows 10%+ (or 10.5 or 11)?

 

[GeneDaniels1963]

http://www.brsquared.org/wine/CalcInfo/HydSugAl.htm
This gives results from 5 different methods of calculating ABV.

 

[VikeMan]

http://www.brsquared.org/wine/CalcInfo/HydSugAl.htm
This gives results from 5 different methods of calculating ABV.

Ah, I see. Those are all variations on a standard wine ABV calculation. Beer ABV formulae are a little different.

 

[GeneDaniels1963]

At the end of the day, it does not make any difference to me the exact ABV of my cider, gruit, or wine. Its just nice to have a general idea when a friend asks, "hey man, this stuff is kicking! How much alcohol is in it?"

For that matter, I have made several that I did not even measure the OG. I just estimated from the ingredients, and that was good enough. But since I have a refractometer, I generally use it.

 

[bwible]

Ah, I see. Those are all variations on a standard wine ABV calculation. Beer ABV formulae are a little different.

This is a lesson we all learn, often the hard way. I made a cider from a kit many years ago and measured the OG at something like 1.044. Being a 100% beer guy at the time, I thought that was too low and proceeded to add brown sugar to about 1.065, thinking I wanted about a 6% cider. This was how I learned that unlike beer - wine, mead and cider ferment basically to zero. And I wound up with something like 8.5% cider.

From 1.093 it will be a respectable strength, probably 8.5 to 9%, depending on where the yeast finishes up. If it were me, I’d let it ferment out the way it is and if you want to drop it down, blend it at bottling time with a weaker beer. Just watering it down will change the profile too much and throw it out of balance. Things like your bitterness, herb flavors, etc.

 

[Sundy]

Let it finish then brew another beer and blend them.Ihave a friend who is obsessed with Flemish browns, they blend beer all the time.