PH Calculator for post fermentation adjustments?

[Unicorn_Platypus]

My understanding is that most brewing calculators are only reliable for making PH adjustments to wort, not beer.

Lately, I've been adding lactic acid post dry hop with great success. I've also made adjustments on certain beers that were tasting a little dull where the acid addition really helped bring the beer to life.

Is there a calculator out there that can be used to estimate how much lactic acid to add to finished beer to adjust to a specific target?

For example, lets say a dry hop charge raised PH from 4.4 to 4.5. How much lactic acid would I need to add to bring it back down to 4.4?

 

[IslandLizard]

I'd say that would be very difficult using a calculator, as you need to know the specific alkaline buffering capacity (alkalinity) of your finished beer, and that can vary wildly.

But you can titrate a (small) sample of a known volume with Lactic Acid, diluted to a certain but known strength. Then calculate the amount of (strong) stock Lactic Acid needed for the whole batch based on that sample value. You'd need a fairly accurate pH meter to do that.

Something similar is done when adjusting acidity in Ciders. They make test kits for that with a color indicator. You'd be adding both Lactic and Malic Acid, each at their indicated volumes.

 

[DuncB]

Related to this, any tool for calculating acid addition to the wort post boil before whirlpool to say drop from 5.0 to 4.3. Using lactic or phosphoric acid.

 

[Unicorn_Platypus]

Related to this, any tool for calculating acid addition to the wort post boil before whirlpool to say drop from 5.0 to 4.3. Using lactic or phosphoric acid.

Bru'n Water should still work for that since you are acidifying wort

 

[DuncB]

Bru'n Water should still work for that since you are acidifying wort

Thanks I'll have a play.

 

[Unicorn_Platypus]

Thanks I'll have a play.

Bru'n Water works if you just use the mash volume

Basically hack it by setting your kettle volume to the mash volume then adjust the phosphoric acid amount until you show current PH

Then adjust the lactic acid amount to target PH and you will know approximately how much lactic acid to use

 

[DuncB]

Bru'n Water works if you just use the mash volume

Basically hack it by setting your kettle volume to the mash volume then adjust the phosphoric acid amount until you show current PH

Then adjust the lactic acid amount to target PH and you will know approximately how much lactic acid to use

Would I not set it ( fake it ) to the volume post boil ? and then input the current pH and the target ph to give me my adjustment figure for the phosphoric acid i intend to use?

 

[Unicorn_Platypus]

Would I not set it ( fake it ) to the volume post boil ? and then input the current pH and the target ph to give me my adjustment figure for the phosphoric acid i intend to use?

You want to use mash volume and fake mash volume to be your kettle volume at the time of the adjustment

then look at the additions it tells you to add

 

[DuncB]

Thanks that was what I was trying to say

 

[mabrungard]

Bru'n Water should still work for that since you are acidifying wort

Yes, as long as you're still dealing with wort. But Bru'n Water can't be used to calculate acid additions for a finished beer. The buffering capacity of wort and beer differ significantly.

With respect to acidifying wort to meet a pre-fermentation pH target, its safer to use the mashing volume in Bru'n Water to calculate a kettle acid addition. That results in a smaller acid addition and you're less likely to undershoot the pH target. That's why its safer to do it that way.

 

[Unicorn_Platypus]

Yes, as long as you're still dealing with wort. But Bru'n Water can't be used to calculate acid additions for a finished beer. The buffering capacity of wort and beer differ significantly.

With respect to acidifying wort to meet a pre-fermentation pH target, its safer to use the mashing volume in Bru'n Water to calculate a kettle acid addition. That results in a smaller acid addition and you're less likely to undershoot the pH target. That's why its safer to do it that way.

I've been using kettle volume (as mash volume) and it's been working well, but I'm generally targeting a pretty liberal range of 5.05 to 5.15, so I target 5.15 (top of the range) and if I overshoot a bit its been working out to hit close enough to a 5.1 target

 

[Roy2Ventullo]

With respect to acidifying wort to meet a pre-fermentation pH target, its safer to use the mashing volume in Bru'n Water to calculate a kettle acid addition. That results in a smaller acid addition and you're less likely to undershoot the pH target. That's why its safer to do it that way.

Hello Martin: I ran across this post while looking for how to acidify wort prior to the boil. I like the idea of being conservative in acid additions BUT I am not clear on where to input mashing volume to calculate kettle acid addition. Any help would be appreciated.

 

[Unicorn_Platypus]

Hello Martin: I ran across this post while looking for how to acidify wort prior to the boil. I like the idea of being conservative in acid additions BUT I am not clear on where to input mashing volume to calculate kettle acid addition. Any help would be appreciated.

This is how I do it:

You kind of need to fudge it in Bru'n Water by making a new copy of your existing recipe

Make the sparge volume zero and then set the mash volume to whatever your kettle volume reads prior to the kettle acid addition.

Next get the PH in Bru'n Water to tie out to whatever the current measured PH by adding or subtracting acid additions.

You will then have your starting PH and starting volume dialed in.

From there see how much additional acid is approximately required to hit your target.

 

[Roy2Ventullo]

This is how I do it:

You kind of need to fudge it in Bru'n Water by making a new copy of your existing recipe

Make the sparge volume zero and then set the mash volume to whatever your kettle volume reads prior to the kettle acid addition.

Next get the PH in Bru'n Water to tie out to whatever the current measured PH by adding or subtracting acid additions.

You will then have your starting PH and starting volume dialed in.

From there see how much additional acid is approximately required to hit your target.

Thanks. Will be trying this.