lowering mash PH

rexbanner · 09-06-2011, 05:33 AM

I forgot to buy acid malt and I need a little something to lower the mash PH. I've been using RO water because I think my tap water, even when filtered, has been a problem. I happen to have some food grade citric acid sitting around. Could I use this? If so, how much?

Or is there something else I can buy at a grocery, healthfood store, or nursery that I could use?

Lastly, the brewing water guide I have recommends skipping acid malt on stouts, but I'm cold-steeping the dark grains for this one, so they won't be in the mash. Am I correct to assume that this negates the advice to skip acid malt?

dragonbreath11 · 09-06-2011, 06:02 AM

Perhaps someone correct me if I'm wrong but Pilsen the town that's responsible for the first pilsner has very soft water, I don't know if they still employ this method but to counteract the soft water they used to do an acid rest at 86F-126F which while time consuming (2 hours+) lowers the mash ph. From my google research I've come to the conclusion that it takes awhile for the ph to go down. Maybe someone can chime in if they have successfully tried this method while testing with a ph meter.. I've also read that you can use any acid ie. vinegar, citric acid, though I'm sure if you use too much it will probably affect the taste of the final product.

**944play** · 09-06-2011, 06:53 AM

Adding calcium chloride and/or gypsum at the rate you probably already should will likely get you most of the way there, which you can estimate using the EZ Water spreadsheet. I've used StarSan to lower a couple mashes with good results, but the acid rest idea is a good one too.

Mashing is pretty forgiving, as indeed are most of the hotside procedures.

mabrungard · 09-06-2011, 01:07 PM

If you were using Bru'n Water, you would be able to assess where your mash pH will end up with the grain bill that you intend for your mash. You would also be able to assess if you would be better off adding the roast malts to the mash to bring the mash pH down in the absence of acid malt.

Using citric acid will be OK excepting that it could add flavor components that you may not want in your beer. Given that you're using RO water, its unlikely that you would need much acid anyhow. So, the citric acid should be OK. Again, Bru'n Water will be a great help there in that you can calculate how much citric acid you might need to hit your target mash pH.

More than likely, you won't need the acid malt or acid in that dark grist when using RO water.

Enjoy.