Diluting post primary

Korpi Brewery

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Hey all.

My receipe for Bavarian weissbier calls for diluting the beer after the primary fermentation. How do I count for this in the brew log? The ratio is 20l to 25l (adding 25% water).

Cheers!
 
Not sure why you would do that. Diluting post fermentation is a nightmare for even the biggest of breweries. You will be directly oxidizing the beer, with the oxygen trapped in the dilution water.
 
Pre boiled cooled water?
The dilution calc on this site will help look in Tools menu tab
 
Not sure why you would do that. Diluting post fermentation is a nightmare for even the biggest of breweries. You will be directly oxidizing the beer, with the oxygen trapped in the dilution water.

In search for the elusive Banana aroma/flavor. Apparently high gravity wort will help in that regard. Bavarian yeast enjoys a little struggle.

Will definetly boil the water hard and cool it down before adding. I'm also hoping there's enough yeasties remaining to sort out the remaining O2s
 
If you want banana just step mash with a 30 minute acid rest at 114 with no ph alteration, or there is always the Hermann maischeverfahren.
 
I can't say I've ever seen a recipe that recommended dilution as part of the process... curious
 
It may be unorthodox, but there's some pseudo-science behind it. Here's my inspiration:

https://braumagazin.de/article/brewing-bavarian-weissbier-all-you-ever-wanted-to-know/

Check out chapter 5 for reference.

It seems I need to break out the calcumulator to estimigate the final ABV. The receipe builder seems to be unable handle this. So... Sample the FG before dilution (gives the ABV) and work out the dilution ratio? Am I right? The Final FG after the dilution doesn't really bring anything to the table.
 
You have a few options but either way you'll need to calculate. You could calculate what the diluted OG and FG would have been by multiplying the starting volume by the gravity points to get the total gravity points and then dividing that by your final volume. And then use those OG/FG numbers to calculate your ABV. Or if it's just the ABV you care about, you could do this directly with the ABV. For example, say your 20L is at 6% right now, here is how I would calculate it:

20 (L) x 6 (%) = 120 (Total Alcohol %)
120/25 (L) = 4.8 (%)

Oxygen will be a real concern since yeast only scavenges O2 when it's reproducing so if you're already at FG none will be removed. Boiling will remove the O2 but cool it as quickly as you can without splashing the water around and picking up more. Good luck!
 
Off topic, god I hate the word pseudo-science.

On topic, it's actual science, ester production goes up with gravity in any beer.

Also On topic, dilution post fermentation scares the bajebus out of me, but I am also a DO nazi, so there is that.

Thanks.
Personally I don't hate words. I hate the lack of my grammar.
I'm also using wild hops on this one (as wild as they get in the northern hemisphere), so many crossroads to choose the wrong bath from.

T
 
You have a few options but either way you'll need to calculate. You could calculate what the diluted OG and FG would have been by multiplying the starting volume by the gravity points to get the total gravity points and then dividing that by your final volume. And then use those OG/FG numbers to calculate your ABV. Or if it's just the ABV you care about, you could do this directly with the ABV. For example, say your 20L is at 6% right now, here is how I would calculate it:

20 (L) x 6 (%) = 120 (Total Alcohol %)
120/25 (L) = 4.8 (%)

Oxygen will be a real concern since yeast only scavenges O2 when it's reproducing so if you're already at FG none will be removed. Boiling will remove the O2 but cool it as quickly as you can without splashing the water around and picking up more. Good luck!

Does this still work with post fermented wort that is yet to be conditioned?
I have a batch that ended up with higher OG than expected that I fermented out to completion (1.060 >> 1.010) giving 6.6% ABV.
I really wanted it to be 5% so can I just "water it down" BEFORE I then condition it? From above I calculate if I add 6 litres to the current 20 litres it should give me 5%. What will the additional water bring to the final beer? You mention Oxygen being a concern but will the conditioning process not scavenge it? Will I spoil the whole batch by doing the addition?
 
It would work post fermentation to bring down your ABV and I agree with your numbers, but oxygen is only taken up by the yeast during active fermentation (used to help build the membranes of new yeast cells) so if fermentation is over little to none will be taken up. If it's really important to you to add the extra water I would boil it for about 10 min, cool as rapidly as possible without splashing, and then immediately and gently add it to the fermenter. If it's a beer you plan to drink sooner rather than later I wouldn't worry about it too much. But if it's one you want to age for awhile you may notice more of a flavor impact should you get much oxygen in.

Cheers!
 
It would work post fermentation to bring down your ABV and I agree with your numbers, but oxygen is only taken up by the yeast during active fermentation (used to help build the membranes of new yeast cells) so if fermentation is over little to none will be taken up. If it's really important to you to add the extra water I would boil it for about 10 min, cool as rapidly as possible without splashing, and then immediately and gently add it to the fermenter. If it's a beer you plan to drink sooner rather than later I wouldn't worry about it too much. But if it's one you want to age for awhile you may notice more of a flavor impact should you get much oxygen in.

Cheers!
Great Thanks for info. I had planned to split the brew - partly to test the dilution option - some in a mini keg and the rest in bottles so we shall see the effect. I just didn't want to spoil the lot.

By the way - the boiling is to drive off any oxygen in the water, right? I had planned to use bottled spring water as that is what I used to brew with (originally with salts etc) I'm sure it's not boiled for sanitary purposes.

And if you mean AGEING the beer - none of my beer lasts that long - conditioning time + 6 weeks is about all my bottles get.
 
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It would work post fermentation to bring down your ABV and I agree with your numbers, but oxygen is only taken up by the yeast during active fermentation (used to help build the membranes of new yeast cells) so if fermentation is over little to none will be taken up. If it's really important to you to add the extra water I would boil it for about 10 min, cool as rapidly as possible without splashing, and then immediately and gently add it to the fermenter. If it's a beer you plan to drink sooner rather than later I wouldn't worry about it too much. But if it's one you want to age for awhile you may notice more of a flavor impact should you get much oxygen in.

Cheers!
Thanks for the insight. Decided against the dilution in the end. There was a lot of Banana and the beer has a pleasant flavor overall. Will enjoy it strong, no need to dilute.
 

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