Distilled water addition (dilution) to (post-boil) wort

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BirchBeer

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Attempting an 8 gallon batch in a 10 gallon boil kettle

Question:

Will diluting the wort with distilled water following the boil negatively affect the chemistry of my wort? Given that it is post boil, does it even matter? I will, of course, calculate the water addition to account for desired gravity.

Thanks in advance.
 
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Will diluting the wort with distilled water following the boil negatively affect the chemistry of my wort? Given that it is post boil, does it even matter? I will, of course, calculate the water addition to account for desired gravity.
You mention "chemistry of my wort". Can you be more specific (pH? mineral ppm? ...)

With concentrated boils, it seems plausible that there are limits (for example, amount of bitterness, amount of NEIPA-ish hop flavors) that one can put into the wort (before dilution). If one has actual experience with these limits, I'm interested. I'm aware of the "forum wisdom" around these ideas - so probably no need to re-type those in this topic.

FWIW, I recently brewed an "all-grain" Amber Ale as a "concentrated" boil (SG 75-ish, OG 44-ish in the kettle) and it came out fine. I'll probably brew another batch with a concentrated boil.

So I'm interested in hearing your thoughts and concerns. I'm also interested in hearing what others have done - especially if one found limits that one may not want to exceed.
 
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BirchBeer

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You mention "chemistry of my wort". Can you be more specific (pH? mineral ppm? ...)

With concentrated boils, it seems plausible that there are limits (for example, amount of bitterness, amount of NEIPA-ish hop flavors) that one can put into the wort (before dilution). If one has actual experience with these limits, I'm interested. I'm aware of the "forum wisdom" around these ideas - so probably no need to re-type those in this topic.

FWIW, I recently brewed an "all-grain" Amber Ale as a "concentrated" boil (SG 75-ish, OG 44-ish in the kettle) and it came out fine. I'll probably brew another batch with a concentrated boil.

So I'm interested in hearing your thoughts and concerns. I'm also interested in hearing what others have done - especially if one found limits that one may not want to exceed.

I'm less worried about the PH post boil as (at least as I understand it) the necessary reactions will have already have taken place). I'm a little more unclear on mineral ppm (possible that it would be the same conclusion as PH - it doesn't matter as the enzymatic reaction have already happened). I'm brewing a Kolsch and adding CaCl to get my chloride content up to 40-50 ppm from my local water profile.

Basically, I'm wondering if the addition of water post boil will change the chloride content in a way that negatively affects the end product.

Alternatively, I'm wondering if it makes more sense to add water pre-boil following removal of my grain (much like a traditional extract brew) as I'll have more room in my boil kettle and the ability to measure and adjust things like PH while it still matters.

Would be great to get thoughts on this.
 

hotbeer

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Is distilled what you started your boil with? If not, I'd think use what ever water you used for the stuff you put in the boil kettle. Then at least the analysis of minerals and stuff will be somewhat the same, even if you added other corrections to the other.

But I could argue with myself either way on that.

Otherwise with either, are you adding more than a gallon?.
 
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BirchBeer

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Is distilled what you started your boil with? If not, I'd think use what ever water you used for the stuff you put in the boil kettle. Then at least the analysis of minerals and stuff will be somewhat the same, even if you added other corrections to the other.

But I could argue with myself either way on that.

Otherwise with either, are you adding more than a gallon?.
Will likely be about 2-2.5 gallons added when all is said and done. I think your idea of keeping the water profile uniform across all added water (especially if adding pre-boil) makes sense to me. Bout to start warming my strike water. So, wish me luck.
 

bwible

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I would guess that distilled water contains no minerals or very little. If you add distilled water post boil, besides diluting the gravity it will also dilute any mineral content. Some minerals are needed by the yeast. I use EZ water spreadsheet. You enter your water minerals from a Ward labs report. Then it has places to enter your grain bill, amounts of water used and what percentage is distilled or RO. Then it gives you the mineral content.
 

marc1

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Calculate your ppm based on the topped up post boil volume
I'm less worried about the PH post boil as (at least as I understand it) the necessary reactions will have already have taken place). I'm a little more unclear on mineral ppm (possible that it would be the same conclusion as PH - it doesn't matter as the enzymatic reaction have already happened). I'm brewing a Kolsch and adding CaCl to get my chloride content up to 40-50 ppm from my local water profile.

Basically, I'm wondering if the addition of water post boil will change the chloride content in a way that negatively affects the end product.

Alternatively, I'm wondering if it makes more sense to add water pre-boil following removal of my grain (much like a traditional extract brew) as I'll have more room in my boil kettle and the ability to measure and adjust things like PH while it still matters.

Would be great to get thoughts on this.
Does your water calculator account for changing mineral concentration from the boil off? If it does, fiddle with it to get the mineral additions you want for the final topped up volume (reduce boil off to 0 for the calculation, etc.)

If not, then the profile you are calculating is not what you have anyway. You could figure it out, and account for it, or just add some mineralization to your top up water.

There's probably going to be some trial and error figuring it out, but unless your top up volumes are a huge % of the final volume you shouldn't get anything crazy either way.
 
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