Is the calcium in mash water lost?

[DrewF]

I was listening to the 2012 AHA water panel (again). I think Martin was the one who mentioned that calcium from the mash water combines with phosphate from the grist, precipitating calcium phosphate.

Did I get that right? Will any calcium from the mash actually make it into the fermenter? If so is there a way to estimate how much?

Thanks in advance.

 

[mabrungard]

Calcium is precipitated in the mash via complexing reactions with phosphates and oxalates. One analytical study I know of showed that to get 50 ppm in the runoff wort, the calcium content in the water at dough in needed to be about 85 ppm. I do not know if that degree of Ca reduction varies with starting Ca concentration or if it is relatively constant without respect to the starting Ca concentration.

 

[DrewF]

Thanks for the reply (and for the informative panel discussion). I start from RO water and try to use minimal additions, so I was thinking my beers might benefit from an additional 50 ppm of Calcium as CaSO4 and/or CaCl2 in the boil to make sure the yeast get their share.

Also, is it feasible to measure Ca at the homebrewing scale? I saw a Vernier calcium ion-selective electrode for sale for < $200, but would it work in wort/beer instead of water?

 

[Kaiser]

I would not worry about the calcium content of the wort. The calcium recommendations generally refer to the brewing water, which had to take the losses in the mash into account.

I think the need for calcium is generally overstated. I have successfully beef clear beers with RO water. I think that watery had a calcium content of about 25 ppm (yes, my RO membrane is old)

Kai

 

[mabrungard]

I agree with Kai that its not necessary to bring calcium up to some minimum to brew beer with. There are plenty of examples of very successful breweries using far less than 50 ppm Ca for their brewing. In my opinion, you can brew effectively with lower Ca. You may just need to be ready to deal with the consequences. Reduced Ca content may result in reduced yeast vitality, yeast flocculation, and oxalate precipitation. All of those problems are surmountable through other measures...pitch bigger...wait longer to flocculate or filter...do more beerstone cleaning.

The analytical study I mention above is from Sierra Nevada. I do not know if they have conducted qualitative studies of their beers to go along with the quantitative measures of calcium that prove to themselves that its worthwhile. I can only assume that they feel it is an easy adjustment that is worthwhile for them.

 

[ajdelange]

If there is a pH reduction relative to distilled water pH those protons came from the precipitation of calcium (and to a lesser extent magnesium) with malt phosphate. As has been pointed out one can brew with even distilled water (and in fact when one speaks of mash efficiency in the way home brewers do 100% means you got the same extract as they did in the laboratory using distilled water). Of course some world class beers are brewed with very low calcium water (Bohemian Pilseners). If there are attached difficulties I'm not aware of them and I brew mostly that kind of beer (Pilseners, that is - I'd like to think of them as world class but I'm really more realistic than that). Maybe I have just figured out work-arounds that I'm not even aware of any more.

Loss to calcium oxalate would be small if any. Fortunately beer contains very little oxalate. Researchers at Lion (NSW) found 9 and 8 mg/L in two of their beers and this is confirmed byKanauchi, Milet and Bamforth who report 45 - 60 mg/kg in malting barley after 5 days decilining to 20 - 22 after 7 days. Beyond that 61% of the oxalate was in the rootlets and 32% in the acrospire with the rest in the kernels themselves. Not enough to strip much calcium but enough to form beer stone on your equipment if you don't take steps to remove it. Nine mg/L is 0.2 mEq, enough to strip 0.2 meq of calcium (4 mg/L).

Yes, you can measure calcium in beer. The problem is that some of it is doubtless bound. To measure that you would have to do a 'digestion' in which the beer is boiled with concentrated sulfuric acid and hydrogen peroxide. This burns of all the carbon and leaves behind the free calcium which can then be measured by more conventional means. ASBC has an MOA, Beer 20, which titrates the beer with EDTA using Eriochrome Black T as an indicator. IOW, they measure the hardness of the beer just as you would measure the hardness of your water. They measure total hardness and then magnesium hardness with the calcium hardness being the difference. I have checked calcium and magnesium in beer by using a modification of this method. I use a high sensitivity chemistry (sold by Hach) which is intended for checking boiler water up to 4 ppm as CaCO3. For normal water or beer this requires that the sample be diluted way down i.e. 99:1 and the answer multiplied by 100. This works very well for beer because not only is the calcium (and magnesium) diluted but so is the color. It should be clear that you can't use the ASBC MOA as is with stout. The method I use does require a visible range spectrophotometer or photometer.

As for ISE's - I have only used sodium ISE's and they are a real pain (slow, non linear response), they are pretty expensive and if you are operating in the non linear region laborious to calibrate and, of course, the calibration requires a series of standards. The situation may be better with calcium ISE's and the range of calcium in beer is usually pretty substantial (i.e. in the linear range of the electrode -guessing here).

 

[dstar26t]

This presentation was an interesting read from Sierra Nevada. I added a section to my brewing spreadsheet that estimates the calcium left in the wort based on their findings. I've done many beers that show calcium in the 20's and as far down as 19 ppm post boil and still ferment and clear excellently. According to Martin's Bru'n Water spreadsheet, the 19 ppm beer had 30 ppm Calcium to start.

 

[Clarky_004]

This presentation was an interesting read from Sierra Nevada. I added a section to my brewing spreadsheet that estimates the calcium left in the wort based on their findings. I've done many beers that show calcium in the 20's and as far down as 19 ppm post boil and still ferment and clear excellently. According to Martin's Bru'n Water spreadsheet, the 19 ppm beer had 30 ppm Calcium to start.

Hi dstar I just tried to load the presentation link you shared but it came up with a 404 error. Do you by chance still have a copy of the presentation or can share their losses through processing. The info is gold.

cheers
Nick

 

[IslandLizard]

Hi dstar I just tried to load the presentation link you shared but it came up with a 404 error. Do you by chance still have a copy of the presentation or can share their losses through processing. The info is gold.

You may have missed you're replying to a thread from 2012. Member @dstar26t hasn't been here for over 4 years.
Sadly, that linked document is now most likely behind mbaa.com's paywall.

Maybe it's still around elsewhere...

 

[BrewnWKopperKat]

Maybe it's still around elsewhere...

Internet Archives Wayback Machine FTW:

https://web.archive.org/web/2012020...idSouth/presentations/2010_11_12JimMellem.pdf

 

[IslandLizard]

Internet Archives Wayback Machine FTW:

https://web.archive.org/web/2012020...idSouth/presentations/2010_11_12JimMellem.pdf

Thank you, very appreciated!
A G-search yielded nothing useful. I guess the Wayback Machine isn't indexed by big G.

 

[BrewnWKopperKat]

Thank you, very appreciated!
A G-search yielded nothing useful. I guess the Wayback Machine isn't indexed by big G.

You're welcome.

I was able to extract/urldecode the link to the presentation URL from the link in the 2012 reply. After that, Wayback Machine has a text box where one can enter URLs directly.

 

[Clarky_004]

You may have missed you're replying to a thread from 2012. Member @dstar26t hasn't been here for over 4 years.
Sadly, that linked document is now most likely behind mbaa.com's paywall.

Maybe it's still around elsewhere...

Good point IslandLizard! I will pay for a subscription there and join. This morning I found a good thread about it on probrewer...check out Ipscman's post on page 3 of the thread Calcium Beyond Mash pH - ProBrewer Discussion Board

 

[IslandLizard]

Good point IslandLizard! I will pay for a subscription there and join.

By no means was I or anyone else inferring you need to subscribe to that organization (mbaa). Fees are hefty and recurring.
There may be good and useful stuff there, I dunno, I never checked them out. Maybe useful for pro brewers?

I feel much information should be free, especially for hobby or casual use.

BTW, did you miss the link to the missing document in question? A new link was provided by @BrewnWKopperKat in post #10.

 

[Clarky_004]

Wow! Thanks BrewnWKopperKat and Island Lizard. I'm still new to the platform and really appreciate it , cheers