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Author Topic: Adjusting ph post mash  (Read 995 times)

Offline Andor

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Adjusting ph post mash
« on: July 12, 2017, 10:40:11 am »
Is there any calculation to figure out roughly how much acid corresponds to drop in ph after the mash or boil?

Offline hackrsackr

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Re: Adjusting ph post mash
« Reply #1 on: July 12, 2017, 03:07:11 pm »
It depends on the actual pH vs. target pH. The scale is logarithmic, so  it'll take slightly more acid to go from 5.2 to 5.0 than from 5.5 to 5.3, even though they're both a net decrease of .2 pH units.

Titration with 1.285 N HCl (or other known acid reagent) to an endpoint to determine the amount of acid needed to get to a known pH level would be the scientific way. Methyl orange is 4.3. Then it's just a slope problem from high school algebra.

BeerSmith has a little calculator about adjusting mash pH. I think it's in the lower left of the session tab.

The LODO guys might have a calculation in their spreadsheet, but they'll have to clarify that.

Regardless, you still have the whole boil to add acid check add more acid if you have to. Keep track of the measurements and additions and you you've basically created your own titration curve.


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