Calculating acid when adjusting boil pH.

[Big Monk]

Perhaps I'm confusing or conflating the two.

Could this be looked at from the simple perspective of "points", whereby if a grist has a maximum potential of 35.5 points per pound per gallon, and one computes via SG that one achieved 27 points, the factor would thus become (for this example) 27/35.5 = 0.76? Or alternately as the grists aggregate fine grind potential derived SG vs. actually measured SG?

I believe the metric equivalent to points per pound per gallon is termed as "Liter Degrees Per Killogram".

Conversion Efficiency is how well you extracted an amount of first wort extract compared to the maximum amount. This will be based around total grain, extract potential (Fine or Coarse As Is) of the mash, and water to grist ratio.

Mash Efficiency is a measure of your achieved preboil mash extract (without sugar adjuncts) that takes into account Lauter Efficiency.

The former is what matters for pH estimation of the mash. If it matters at all.

 

[SanPancho]

Anybody have strength/normality of 75% phosphoric?

 

[Silver_Is_Money]

Anybody have strength/normality of 75% phosphoric?

It varies with target pH. What target pH do you want it for?

 

[Silver_Is_Money]

Anybody have strength/normality of 75% phosphoric?

In the end it's acid strength is not as highly variable as for weaker acids.

5.0 pH : 12.141 mEq/mL
5.1 pH : 12.164 mEq/mL
5.2 pH : 12.191 mEq/mL
5.3 pH : 12.223 mEq/mL
5.4 pH : 12.262 mEq/mL
5.5 pH : 12.310 mEq/mL
5.6 pH : 12.370 mEq/mL
5.7 pH : 12.444 mEq/mL
5.8 pH : 12.535 mEq/mL

 

[SanPancho]

5.4 generally in mash, although we also use for late kettle adjustments, fermenter, etc.

i need to know numbers for each? Maybe An average?

 

[Silver_Is_Money]

5.4 generally in mash, although we also use for late kettle adjustments, fermenter, etc.

i need to know numbers for each? Maybe An average?

In order to know where you are going, you first need to know where you are. It seems as if you could use both mash and kettle pH managing software. Or alternately use:

(Initial_pH_Grist/Wort - Target_pH_Wort) = mEq's required/(34 x Kg_Grist)

Solve for mEq's Required. Then apply the acid (or base) strength appropriate to your target pH.

Example for 50 mEq's required to hit a target of 5.4 pH:

50 mEq / 12.262 mEq/mL = 4.08 mL of 75% Phosphoric Acid to be added.

If you can derive "Initial_pH_Grist/Wort" the rest is easy. No software required.

 

[SanPancho]

Already have mash calc. So realistically this is more for kettle and ferm i guess. The kolbach equation works well enough for us. Typically within.1 of target. But our phosphoric just went down to 75 from 85. Hence the need for new figure to plug into the spreadsheet.