Author Topic: Mash ppm in = Mash ppm out?  (Read 752 times)

Offline The Rabid Brewer

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Mash ppm in = Mash ppm out?
« on: October 03, 2010, 03:44:15 PM »

Any references as to how much of the minerals in the mash water make it to the kettle?

To a first order, ppm in = ppm out.

However, there are certain other factors involved such as the precipitation of Ca by HCO3.

Also, will the grain retain water but not minerals such that the mash water out has a higher ppm? Or is it just the opposite in that the grain retains minerals and not water making the mash water out have a lower ppm?

Brian
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Offline adrie

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Re: Mash ppm in = Mash ppm out?
« Reply #1 on: October 04, 2010, 12:28:32 AM »
Interesting question.

Ca does not precipitate with HCO3 in the mash but with phosphates.
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Offline dcbc

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Re: Mash ppm in = Mash ppm out?
« Reply #2 on: October 04, 2010, 09:29:18 AM »
I asked this question with reference to grain absorption a few months ago.  The closest thing to a consensus I got on the subject was that it was reasonable to assume that the grain would absorb the minerals dissolved in the mash water they absorbed.  In other words, for purposes of determining kettle mineral additions, the first runnings would not be presumed to have a higher concentration of minerals as a result of the grain absorbing water, but not minerals.

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Offline The Rabid Brewer

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Re: Mash ppm in = Mash ppm out?
« Reply #3 on: October 04, 2010, 09:32:31 AM »
I'm already doing that in my brewing, but my technical curiosity got the better of me and I'm looking for references to work that has been done in this area to actually measure what's going on.
I asked this question with reference to grain absorption a few months ago.  The closest thing to a consensus I got on the subject was that it was reasonable to assume that the grain would absorb the minerals dissolved in the mash water they absorbed.  In other words, for purposes of determining kettle mineral additions, the first runnings would not be presumed to have a higher concentration of minerals as a result of the grain absorbing water, but not minerals.


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Offline dcbc

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Re: Mash ppm in = Mash ppm out?
« Reply #4 on: October 04, 2010, 09:33:19 AM »
Good luck. 
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Offline thcipriani

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Re: Mash ppm in = Mash ppm out?
« Reply #5 on: October 04, 2010, 07:06:30 PM »
According to Fix in Principals of Brewing Science, "There is of course no direct correlation between finished-beer mineral levels and the mineral content of brewing liquor" (Fix 15).

This quote also makes sense a posteriori - when you think of the variability that minor and major mash parameters have on pH and gravity it makes sense that there would not be any adequate way to predict the expected mineral content of your mash runnings or the final mineral content of beer. Things like mash thickness, grist composition, pH and various buffering systems would make this a nearly impossible calculation.

Interestingly, while the conversation in this thread has been about the minerals that are lost in the malt and not about the minerals that malt contribute to the beer. I ran across an article abstract in the American Society of Brewing Chemist Journal about malt modification, mashing parameters and their affect on the mineral composition of wort might be of some interest:
http://www.asbcnet.org/journal/abstracts/backissues/35-01.htm
Tyler Cipriani
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