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A Brewing Water Chemistry Primer

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Silver_Is_Money

Larry Sayre, Developer of 'Mash Made Easy'
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My response #2 in post #1674 to Big Monk's point #2 in his post #1673 was between he and I, whereby both he and I know the pH at which Rochefort mashes. This "insider info" was not made public, but now that it is, the intent was that to duplicate Rochefort's documented mash pH one must know not only the ppm's of their water (such that they are also documented) but to hit their mash pH via duplicating their water is to hit their mEq's is to know their water to grist ratio. Another piece of the puzzle that was between he and I is that we both know that Rochefort does not adjust their mash pH. Thus my #2 in response to his #2 could indeed appear cryptic to someone other than he or myself, but in the end I was directly replying to him, and not to everyone else. Thus the logic may easily be missed by all but Big Monk and myself. Such is often the case for public forum replies.

Now on the other hand if one knew Rochefort's mash water mEq's then one would potentially be able to target duplication of their mash water mEq's via a plenitude of differing mash water mineralization ppm's and mash water to grist ratios. Thus taken by and of themselves, merely knowing Rochefort's mineral ppm's is flawed as I indicated. And if a book says to use Rocheforts mineralization ppm's (I.E., if it tells you to use their "water profile") it is indeed deceiving you if that is all of the instruction it offers to you.

PS: Not that it matters to my argument above, but Rochefort intentionally mashes at a pH that most typically falls between the extremes of 5.8 low and 5.9 high. One has to presume this to be as measured at room temperature (but in honesty, their pH measurement temperature is not specified in available data, at least as far as I can tell).
 
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beervoid

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No, I'm telling you that in 7 gallons of 50 ppm calcium ion water there are twice the mEq's of Ca++ ions as for 3.5 gallons of 50 ppm water.
If I understand you correctly the water to grist ratio influences how much ions are absorbed into the mash.
Thinner mash is more ions, thicker mash is less.

Does MME take into account water to grist ratio for calculating total ions in mash.
 

Silver_Is_Money

Larry Sayre, Developer of 'Mash Made Easy'
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Does MME take into account water to grist ratio for calculating total ions in mash.
It's internal math does not specifically utilize the water to grist ratio directly as such, seeing as the ratio is merely a secondarily derived corollary involving grist weight and water volume, but effectively (since it accounts for these ratio building block components) you could indeed say that it does, as its ions in the mash output are in full accord with the water to grist ratio. MME utilizes mEq's, and for pH adjusting acids and bases it also applies their dissociation constants, which alter their relative mEq/L or mEq/gram "strengths" in accord with ones desired pH target. And for the unique case of Ca(OH)2 it also factors in that while this minerals OH- ions are driving mash pH upward, its Ca++ ion is simultaneously driving mash pH downward. And uniquely, MME attempts to merge the derived Ca++ and Mg++ pH shifting math model formula derived output per Kolbach with the real world observations as to these ions pH impact for high levels of these ions as per Taylor. Thus for MME Kolbach becomes a variable and not a fixed formula as per the other calculators, whereby as Ca++ and Mg++ mEq's are increased within the mash water, the impact of Kolbach's math model output upon downward pH shift is progressively diminished.
 
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Big Monk

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It's internal math does not specifically utilize the water to grist ratio directly as such, seeing as the ratio is merely a secondarily derived corollary involving grist weight and water volume, but effectively (since it accounts for these ratio building block components) you could indeed say that it does, as its ions in the mash output are in full accord with the water to grist ratio. MME utilizes mEq's, and for pH adjusting acids and bases it also applies their dissociation constants, which alter their relative mEq/L or mEq/gram "strengths" in accord with ones desired pH target. And for the unique case of Ca(OH)2 it also factors in that while this minerals OH- ions are driving mash pH upward, its Ca++ ion is simultaneously driving mash pH downward. And uniquely, MME attempts to merge the derived Ca++ and Mg++ pH shifting math model formula derived output per Kolbach with the real world observations as to these ions pH impact for high levels of these ions as per Taylor. Thus for MME Kolbach becomes a variable and not a fixed formula as per the other calculators, whereby as Ca++ and Mg++ mEq's are increased within the mash water, the impact of Kolbach's math model output upon downward pH shift is progressively diminished.
Translation: No, it doesn’t. But it kind of does.

;)
 

ep_brew

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If you're trying to better understand water like me, I think Silver_Is_Money brings up a good point about BIAB or No Sparge brewers blindly following recipes that were probably written by Fly Sparge or Batch Sparge brewers. I don't have a natural science background and I've been learning more about water chemistry through the posts here and John Palmer's How To Brew 4th ed., chapter 21. Working through the Kolbach equation in the book I started to understand whats involved. I got the Briess malt data from How To Brew and the Weyermann from Silver_Is_Money's posts. This is just a basic example, the pH software guys and the Water book have more developed models.

A recipe for a North American Lager:
Batch size = 5 gallon (19 liters)
Mash pH target = 5.4
Distilled water with 50 ppm added calcium

Grain Bill
99% Briess Brewers Malt, 11 lbs (5 kg) * 5.0 mEq/kg to target 5.4 pH = 25 mEq
1% Weyermann Acidulated Malt, 1.75 oz (0.05 kg) * -320 mEq/kg to target 5.4 pH = -16 mEq

The grain bill has 25 - 16 = 9 mEq of alkalinity.

Water
50 ppm calcium / 20 equivalent weight = 2.5 mEq/Liter

Kolbach's Residual Alkalinity in mEq/Liter = alkalinity (0 distilled water) - ((2.5 calcium / 3.5) + ( 0 magnesium / 7))

The water has -0.7 RA per liter.

Fly Sparge or Batch Sparge, 3.5 gallon (13.25 liters) * -0.7 RA = -9.3 water RA
BIAB or No Sparge, 7 gallon (26.5 liters) * -0.7 RA = -18.6 water RA

Doubling the water in the mash has doubled the RA. Both mashes are 50 ppm calcium.

Mash
Fly Sparge or Batch Sparge, 9 mEq malt alkalinity + (-9.3 water RA) = -0.3 acidity
BIAB or No Sparge, 9 mEq malt alkalinity + (-18.6 water RA) = -9.6 acidity

For these two mashes with 50 ppm calcium to be the "same", the BIAB or No Sparge mash has 0.3 - 9.6 = -9.3 mEq acidity that needs the neutralized.

Sodium bicarbonate has 11.8 mEq/L alkalinity. 9.3 / 11.8 = 0.8 grams of baking soda required.

I think with all the knowledge about water now, there's a lot of benefit to using one of the water calculators and No Sparge / BIAB brewers should know the calcium and magnesium in their water at the same ppm of the recipe, will acidify their mash pH more because you're increasing the total quantity of calcium and magnesium in the mash. I think I followed the book correctly but let me know if I made any mistakes.
 
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