Czech Pilsner with Distilled water

[archthered]

I want to make my first Czech Pilsner using a 2 step decoction, no acid rest, protein rest and two sacc. Anyway my water sucks, I routinely use distilled water (yes I know I need to get an RO system) in some percentage, often close to 100%. I had planned on using straight distilled but I didn't order any saurmalt so my ph is going to be high. There is no LHBS for 60 miles and I really don't want to have to order 1lb and pay for shipping on it since shipping will be more than the malt... and I don't really want to wait to brew. I plan on adding phosphoric acid to drop the ph.

My biggest question is will adding phosphoric acid negatively impact my pilsner? I've never added it to mash water but I know it is often used, to the point that Bru'n water includes it in their software. I am just unsure about adding it to a pilsner since it is so light and water chemistry so important for the style.

Secondly I was considering adding a touch of my local crappy water to the mash, literally about 5%, to up the amounts of some of the minerals that I can not get in the distilled water in the quantities needed without throwing other things out of balance. The question here is is it worth it?

Target Mash Profile according to Bru'n, using Pilsen: Ca 7, Mg 2, Na 2, Sulfate 8, Cl 6, Bicarb 16

Mash Profile with distilled only, after additions: Ca 24, Mg 0, Na 0, Sulfate 0, Cl 42, Bicarb -37 (from acid)

Mash Profile with small addition of crappy water, after additions: Ca 22, Mg 2, Na 3, Sulfate 3, Cl 35, Bicarb -29

Generally speaking the 5% addition is closer to the target, Mg, Na, Sulfate etc, but I wonder how much of that will matter/make a difference vs just being how the water there is. I know that since I'm decocting I don't need to worry about the Ca as much but since I'm only doing a short protein rest and no acid rest I want some amount of Ca and I need a bit of Cl. Anyway I appreciate any thoughts.

 

[Yooper]

Either of those is fine- I like my calcium at 40 ppm but that's for me to try to reduce beerstone formation. If your mash pH is at 5.3-5.4 (and using phosphoric acid is a good choice), then those numbers don't matter all that much.

 

[mabrungard]

It shouldn't take much acid to bring that mash's pH down. Phosphoric should be fine.

 

[archthered]

Thanks

 

[ajdelange]

The amount of acid required depends on the malts used. I have data on three pilsner malts. To pH 5.5 one of them requires 4 mEq/kg another 14 and the third about half way in between. As to which acid to use we might argue that a German brewer would use sauergut or sauermalz and that therefore lactic acid is more authentic or that lactic contributes secondary flavors but as far as getting the pH right phosphoric (or hydrochloric or sulfuric or citric...) will do.

 

[archthered]

I forgot the saurmalz, I have Weyermann Bohemian Pilsner malt, fully modified not floor malted. With my CaCl2 addition (.25g/gal) Bru'n Water says I still need 5ml/gal of 10% phosphoric acid to hit a pH 5.4. I do not think the software accounts for different types of pilsner malt.

 

[ajdelange]

Clearly the best thing for you to do is to forget calculators and do a test mash. Also forget profiles. Just add 25 - 100 mg/L CaCl2.0H2O. The lower end of the range is closer to the published Pilsen calcium content but the higher end of the range will give a better beer (extra chloride improves body, sweetness).

 

[HausBrauerei_Harvey]

I just did my first decocted pilsner, I also used Weyermann Bohemian Pilsner malt, fully modified not floor malted. I did the same general mash schedule you are targeting and used phosphoric acid (what I always use) to bring the pH down. This was my 5th try at recreating a north german style pils (like Jever Pilsner), and the decoction really helped to get the beer tasting way more authentic than my past attempts, which were also good but not as good as this one. I'll be decocting all my pilsners going forward, I was skeptical but it does add that extra complexity in the flavor I was lacking previously.

 

[SpeedYellow]

I've made a couple beers with RO water and little to no mineral additions, but quit that idea promptly. IMHO there's a good reason for the minimum 50 ppm Ca recommendation.

Like was said above, you'll need very very little acid for this. For 100% distilled water, like 1 mL of lactic acid is enough. Maybe less. Point being it doesn't matter what type of acid since you'll need hardly any.