Author Topic: How to calculate kettle acid addition  (Read 683 times)

Offline Robert

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How to calculate kettle acid addition
« on: January 28, 2018, 07:42:37 PM »
Say I want to mash and conduct most of the boil at pH 5.4, and reduce wort pH to 5.0 at the end.  How do I calculate the acid addition, and just how late in the boil can I add it? (I'm thinking I want to keep pH up as long as possible to facilitate break and hop utilization.) 
Rob Stein
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Offline klickitat jim

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Re: How to calculate kettle acid addition
« Reply #1 on: January 28, 2018, 08:50:03 PM »
Kai might still have his calculation on his website kaiserbrew I think...

http://www.braukaiser.com
« Last Edit: January 28, 2018, 08:52:44 PM by klickitat jim »

Offline Robert

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Re: How to calculate kettle acid addition
« Reply #2 on: January 28, 2018, 09:01:05 PM »
Kai might still have his calculation on his website kaiserbrew I think...

http://www.braukaiser.com
I've looked there and don't think there's anything on kettle acidification. Thanks though, I'll look again.

EDIT nope still don't see anything.   I know somebody around here will help out before next brew day! :)
« Last Edit: January 28, 2018, 09:07:58 PM by Robert »
Rob Stein
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Offline klickitat jim

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Re: How to calculate kettle acid addition
« Reply #3 on: January 28, 2018, 09:12:37 PM »
That's where I found it when I was brewing my Rube Goldberg German lager. It actually might be in my Rube Goldberg thread. My memory is that kettle acid did not enough to register as a thing for me. But I'm sure others will vehemently disagree.

Offline klickitat jim

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Re: How to calculate kettle acid addition
« Reply #4 on: January 28, 2018, 09:17:25 PM »
I might have it on my tablet at home if the resident experts fail you.

Offline Robert

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Re: How to calculate kettle acid addition
« Reply #5 on: January 28, 2018, 09:20:38 PM »
I might have it on my tablet at home if the resident experts fail you.
That ain't gonna happen! It'll be raining knowledge around here.  Whether I use it or not. Just wanna know.
Rob Stein
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Offline klickitat jim

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Re: How to calculate kettle acid addition
« Reply #6 on: January 28, 2018, 09:46:32 PM »
What can come close is to use your mash pH calculator. Boiling doesn't change your buffering...

Reworded, boiling doesn't change MY buffering, not enough to matter.
« Last Edit: January 28, 2018, 09:49:05 PM by klickitat jim »

Offline Robert

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Re: How to calculate kettle acid addition
« Reply #7 on: January 28, 2018, 09:50:06 PM »
What can come close is to use your mash pH calculator. Boiling doesn't change your buffering...
That's what I just started playing with.  Calculate my desired mash pH,  I get 0.15 ml/gal lactic 88.  pH 5.0 needs 0.85. Subtract, the difference is 0.7, multiply that by kettle volume I'm trying to adjust and add that. Maybe?
Rob Stein
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Offline homoeccentricus

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Re: How to calculate kettle acid addition
« Reply #8 on: January 28, 2018, 09:56:16 PM »
Big Monk has the calculations embedded in the new version (7) of the low oxygen brewing spreadsheet, which is now in beta...
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Offline The Beerery

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Re: How to calculate kettle acid addition
« Reply #9 on: January 28, 2018, 10:19:36 PM »
Big Monk has the calculations embedded in the new version (7) of the low oxygen brewing spreadsheet, which is now in beta...


They have been in all our sheets. 


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Offline Big Monk

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Re: How to calculate kettle acid addition
« Reply #10 on: January 28, 2018, 11:14:54 PM »
Big Monk has the calculations embedded in the new version (7) of the low oxygen brewing spreadsheet, which is now in beta...


They have been in all our sheets. 


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Yup. I started doing it for Bryan in 2016. We have mineral acid and Sauergut calcs for mash, kettle, and 10 min pH reductions.
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Offline Robert

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Re: How to calculate kettle acid addition
« Reply #11 on: January 28, 2018, 11:26:15 PM »
Big Monk has the calculations embedded in the new version (7) of the low oxygen brewing spreadsheet, which is now in beta...


They have been in all our sheets. 


Sent from my iPhone using Tapatalk

Yup. I started doing it for Bryan in 2016. We have mineral acid and Sauergut calcs for mash, kettle, and 10 min pH reductions.
Where is this spreadsheet? I didn't spot a link on LOB.
Rob Stein
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Offline Big Monk

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Re: How to calculate kettle acid addition
« Reply #12 on: January 28, 2018, 11:30:17 PM »
Big Monk has the calculations embedded in the new version (7) of the low oxygen brewing spreadsheet, which is now in beta...


They have been in all our sheets. 


Sent from my iPhone using Tapatalk

Yup. I started doing it for Bryan in 2016. We have mineral acid and Sauergut calcs for mash, kettle, and 10 min pH reductions.
Where is this spreadsheet? I didn't spot a link on LOB.

http://www.lowoxygenbrewing.com/wp-content/uploads/2018/01/Low-Oxygen-Brewing-Software-v.6.6-Standard.xlsx

That’s the current (soon to be retired) version of the spreadsheet.
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Offline mabrungard

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Re: How to calculate kettle acid addition
« Reply #13 on: January 28, 2018, 11:37:31 PM »
The proper addition is the amount of acid needed to take the MASH pH from the existing pH to the desired pH. The wort in the kettle has the same buffering as in the mash. Of course, this assumes that you have properly treated the sparging water to neutralize excess alkalinity.

PS: You can't use this trick to change beer pH. Beer has more buffering and it takes more acid per tenth of pH unit reduction in beer than in wort.
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Offline Robert

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Re: How to calculate kettle acid addition
« Reply #14 on: January 28, 2018, 11:45:02 PM »
The proper addition is the amount of acid needed to take the MASH pH from the existing pH to the desired pH. The wort in the kettle has the same buffering as in the mash. Of course, this assumes that you have properly treated the sparging water to neutralize excess alkalinity.

PS: You can't use this trick to change beer pH. Beer has more buffering and it takes more acid per tenth of pH unit reduction in beer than in wort.
So in my example in reply #7, the correct kettle addition would be simply 0.7ml total?  (After my previous post it occurred to me that the buffering would remain constant. But i tried the LOB spreadsheet and it seems to confirm my initial estimate.)
Rob Stein
Akron, Ohio

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