Gypsum in mash

(That's water to the rest of us!) Beer is about 95% water, so if you want to discuss water treatment, filtering etc this is the place to do it!
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weiht

Gypsum in mash

Post by weiht » Sat Sep 24, 2011 2:49 pm

Hi there, got a qns that came back to me... If i add gypsum into the mash to lower the ph to 5.2, does the Calcium and Sulphate addition carry over into the boil and affect the overall profile of the beer, or that gets left behind in the mash? Ok example if i need 1g of gypsum to match a profile using the water calculator and at the same time i also need to use it to lower mash ph, if i add 1g of gypsum into the mash, will the 12.3 and 29.5 Calcium and Sulphate carry over to the overall beer profile, as though i have added it to the boil. Or does it only stay in the mash after using it to to lower the ph, and i will be required to add the gypsum again into the boil???

If thats the case, what happens if i just need to add say 1g to achieve me tgt profile, but my mash ph may be high and i need to add 3g to lower ph... Wont it screw the calcium and sulphate levels in the overall beer? Or if im brewing a lager, and use gypsum to lower the mash ph, would that add the unwanted higher levels of calcium into the finished beer as well?

i use mainly gypsum to lower n sodium bicarbonate to increase ph in mash if needed, and maybe just a teaspoon and half of gypsum to boil 6gallon of ale. But, i thinking of revisiting this issue of late, mainly for mashing since that's where the magic of conversion happens, and that led me to wonder again if the salts does carry over to the finished beer's water profile... I would not want to keep adding and end up with something thats over the top!!!

Also thinking if i should acidify the sparge water a little to reduce tannin extraction... Is there a water calculator for the mash, where u enter the mash ph and it tells you what salts you need and how much to add to bring it to 5.2? Something like graham's water calculator but for mash...

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Aleman
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Re: Gypsum in mash

Post by Aleman » Sun Sep 25, 2011 11:45 am

Don't use Gypsum to treat water for lager brewing!! Lagers cannot (with some exceptions like Dortmunder Export) tolerate high levels of sulphate.

Excess calcium is not a problem in the mash or boil, indeed having an excess is desirable as it is such an important cofactor in so many brewing reactions.

The issue is having an excess of sulphate (and or probably chloride too) which can increase the perception of bitterness making a hoppy beer unacceptably harsh.

Calcium Chloride is another brewing salt to have on hand as it can supply calcium without increasing the perception of hop bitterness . . indeed it promotes a softer rounder mouth feel and palate fullness.

weiht

Re: Gypsum in mash

Post by weiht » Sun Sep 25, 2011 1:48 pm

Is harsh bitterness solely on the levels of sulphate alone or the sulphate to chloride ratio? I understand that when the ratio biased towards sulphate is for a bitter effect and chloride is for a malty effect.

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Aleman
It's definitely Lock In Time
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Location: Mashing In Blackpool, Lancashire, UK

Re: Gypsum in mash

Post by Aleman » Sun Sep 25, 2011 5:22 pm

It does depend on the ratio, but the absolute level does matter as well . . . . . 450ppm of sulphate will always have a harsh bitterness even if there is 450ppm of Chloride in there as well (1:1 ratio).

For some styles though (Bohemian Pilsner, Ocktoberfest / Maerzen, Kolsch) you need the sulphate levels to be as low as you can achieve but still need to increase calcium . . . Hence using calcium chloride . . . and perhaps looking at alternative methods of alkalinity reduction rather than CRS

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