Determination of phosphorus in wort and beer

[1MadScientist]

I am in a stage 3 CKD an am asking if you guys could provide any information of the amount of phosphorus in finished beer.

I need to count my daily phosphorus intake.

I would like to continue brewing beer. Does any one style have lower amounts? It seems that there are lesser amounts in lower gravity beer.
What should I brew? Can I continue with an all malted barley recipes?

What general phosphorus mg #'s can I use?

MS

 

[drewbacca]

Hi, I was wondering if you've had any luck with your research? My dad was recently diagnosed with kidney disease and has been depressed about his new diet. He just told me that he can no longer drink beer because of the phosphorus content. I was wondering how you've been dealing with it, and if you were able to find or create any low-phosphorus recipes you could share with me. Would really love to brew the old guy something he can drink.

Thanks, and good luck to you!

 

[ajdelange]

Malt contains a lot of phosphorous - up to a couple of percent of its weight as the pentoxide if I recall correctly. It is the reaction of this phosphate with calcium that we partially count upon to release protons and lower mash pH. Obviously, the more calcium, the more phosphate precipitates but there is doubtless lots left. You could WAG how much precipitates from Kolbach's observation that one equivalent of calcium produces 1/3.5 mEq of H+ and looking at the reaction:

10Ca++ +6H2PO4- + 2H20 ---> Ca10(PO4-3)6(OH)2 + 14H+

Thus each mEq H+ was produced by removing 6/14 mmol of phosphorous. If you had Ca++ at 10 mEq/L then you'd get (to knockout) 10/3.5 mEq protons and (10/3.5)*(6/14) mmol of phosphorous removed per liter of water. I leave you to work from the 1 - 2% phosphorous as the pentoxide to remaining phosphate in the beer but I guessing it's quite a bit.

If you have Briggs, Hough, Stevens and Young you can look it up in the chapter (Vol II) on beer constituents.

 

[1MadScientist]

Hi, I was wondering if you've had any luck with your research? My dad was recently diagnosed with kidney disease and has been depressed about his new diet. He just told me that he can no longer drink beer because of the phosphorus content. I was wondering how you've been dealing with it, and if you were able to find or create any low-phosphorus recipes you could share with me. Would really love to brew the old guy something he can drink.

Thanks, and good luck to you!

At the time of my post a second metabolic panel confirmed a low GFR # by my GP. I started google searching and that seemed to indicate to me that I must have high levels of phosphorus. By the time I saw a nephrologist and got a result back with a more extensive blood test, showed a normal level of phosphorus. I was elevated with uric acid and low in vitamin D. After one cycle of an office visit to try a diet in "low purine", did not work, I was put on Allopurinol.

I never revealed to my doctor that I drink beer, so was never given an order to stop.

Phosphorus in beer (to me) seems to be based on the strength of the beer, WAG.

So I'm brewing and drinking beers below 5% and that seems to work for me.

My GFR and creatinine have even slightly improved, so I'm not worrying about that, atm.

Best of luck with your Dad.
MS