Diluting with water to lower FG

[Kershner_Ale]

Anyone tried this? I have a Munich Dunkel that stalled out on me. I keged and lagered it knowing the FG was too high (1.023). I'd like to get it down to 1.016 or so. Thinking about using Beersmith to calculate the dilution rate and see what hapoens. Just curious of other's experience.

 

[jsprinceiii]

Should be fine!
Personally, I would pitch a small starter..

 

[Kershner_Ale]

Should be fine!
Personally, I would pitch a small starter..

I'd consider that but I'm short on time to get it carbed and ready for a competition.

 

[Calder]

From 23 to 16 you will need to dilute by about 50%. That is, you will need to add slightly less than 2.5 gallons of water to 5 gallons of 1.023 beer to get it down to 1.016.

Doesn't seem like a very good idea; but I don't know any details of the beer.

If you do dilute the beer, make sure you boil the water first to get rid of entrained O2, which will stale the beer.

Some of the big boys actually do this as part of their process. It allows them to brew more beer with a given amount of fermentation volume..

 

[davehuge]

I don't think dilution is a good idea. You'll be diluting the sweetness, but also the bitterness and the body, as well as malt and yeast flavour. You'll end up with a watery beer. Very different to a beer that had actually finished 1.016. I'd leave it as is.

 

[Qhrumphf]

If you do dilute the beer, make sure you boil the water first to get rid of entrained O2, which will stale the beer.

I had thought about doing this once, not by mistake but by intentional design. The idea was to brew concentrated in one barrel, and then dilute it down in the second to fill the headspace but hit my target FG.

I was lucky enough to ask John Palmer about the plan before I did it (or rather, my club did it, this was a big club project of a full 55 gallon bourbon barrel beer). Oxygen in the water will be more than enough to stale the beer. If your read Palmer and Colin Kominski's "Water" book, you'll see that even AFTER YOU BOIL water, it still contains enough to oxidize, and would be especially so if you diluted 50% to reach the gravity that you want to. The only way to sufficiently remove enough O2 from water not to be a danger would be to use a water de-aerator, which I know I don't have and I'm doubting that you do either.

Point is, I wouldn't risk it. Pitching an active starter of high attenuating yeast, or brew another lower FG batch and blend.

Cheers.

 

[Calder]

If your read Palmer and Colin Kominski's "Water" book, you'll see that even AFTER YOU BOIL water, it still contains enough to oxidize.

Interesting. Will have to read up on it. I've never done it, but have considered it to get lots of Belgian yeast flavor in a low abv beer. Flavor supposedly is 4x with gravity.

 

[oakbarn]

I like a little water with a wee Scotch but not with beer !

 

[Qhrumphf]

Interesting. Will have to read up on it. I've never done it, but have considered it to get lots of Belgian yeast flavor in a low abv beer. Flavor supposedly is 4x with gravity.

Now that I've got the book in front of me, boiling under atmospheric pressure (not in a vacuum) reduces the DO level in water to about 4 ppm. The accepted safe level is 50 ppb, which is obviously a big difference. Many commercial breweries who brew concentrated and top up with water post-fermentation aim for a max of 30ppb with a goal 10ppb or less.

 

[Kershner_Ale]

Turns out The Brewing Network Sunday Session just had a segment on this topic. Doc talked about three techniques for lowering final gravity. He mentioned the Beano trick, pitching fresh yeast, blending with another beer, and diluting with water. He used the last two for a Baltic Porter that finished high. The brewcasters all tried a sample of the original, the blended, and the water diluted beer. Everyone preferred the later two over the original. No one mentioned a watered down taste but noted diluting with water and blending give you two different beers, each having pluses over the other.

Interesting note on boiled water still having too much oxygen. I think for a short term fix, such as bottling and judging soon after for a competition, I wouldn't worry about oxidation as much. But definitely if keeping it much more than a week or two. I think I'll try diluting with water but only try it for half the batch. Then I can compare the two over time.