Added too much gypsum - how to improve beer in keg

[JiP]

I made a mistake when brewing a hoppy porter. I added gypsum to the mash, which pushed the pH the opposite direction than I intended (lowered, i.e. more acidic rather than balancing the acidity from dark grains.) Gypsum also added more sulfates to my local water that's already high in sulfates. I'm not sure what the low acid may have done, but the effect of sulfates is supposed to be more 'metallic' or harsh bitterness, which is what the beer tastes like two months after brewing (it's in a keg).

Has anyone had experience correcting this? What would you suggest to balance the beer or remove the off-taste?

I had made the same mistake before. I was new to all-grain, and added gypsum for dark beers when I should have added chalk or baking soda. I had bottled those, and had oak-aged, dry hopped, etc. and waited almost a year but can still taste the off flavor. This is my first kegged mistake, so I have the opportunity to add "something." Anyone know what that something should be?

Thanks

 

[alane1]

I don't think there is any remedy for removing minerals, but what you could probably do is make another batch with soft water and really push the malt flavor. Then blend both batches 5o/50. Hope this helps.

 

[Yooper]

Well, the effect of gypsum on pH is negligible so that's not an issue. Most people have too-high pH and not too-low pH so unless you added a ton of acid to the mash, the pH wouldn't be too low.

Unfortunately, high sulfate may not give a good flavor to the beer and if it's combined with high chloride you could get a very minerally finish. I generally use low sulfate (and low chloride) water for most beers.

You shouldn't add chalk to your mash in any case, but sometimes alkalinity in other forms is useful. (Please see the brew science area of the forum for more on this).

 

[mabrungard]

As post #2 said, blend this beer with a less mineralized beer to dilute the sulfate to a palatable level. There is no other treatment to reduce the effect of sulfate.

 

[JiP]

Thanks for the replies.