Newb water chemistry question

[beerisyummy]

Hello fellow zymurgists,

I am an extract brewer, after 25 batches getting ready to make my first forays into all-grain brews. The specifics:

• My setup will be BIAB and I will stay with 5 gallon batches and bottle conditioning at least for now.
• I use an activated charcoal water filter, which does a good job of removing chlorine/chloramine flavor and odor, but I'm not clear on how it changes the water chemistry as a whole. My assumption would be that this renders the water basically "tabula rasa" but I don't really know.
• I'm planning on my first try being something reliable and straightforward, like a California Common.

I understand that mash pH is an important factor to be dealt with, so I am trying to understand a little bit about it - I am no chemist, by the way, I am a musician! - so I'm not into heavy calculations, just want to figure out some decent technique.
Palmer says: "It is important to understand that the mash pH will decrease slowly throughout the hour-long mash, that conversion happens relatively quickly, and that enzymes can be rapidly denatured by a combination of non-optimum pHand high temperature. In other words, attempting to fix a mash pH that is too low or too high may take too long to be effective. You will probably do better by planning ahead with water or recipe changes for the next batch." (How to Brew, 4th ed. 2017, pg. 341)

And now to the question. Should I simply brew away, take a baseline pH measurement so I know what to "tweak" next time; OR should I pre-emptively adjust the water somehow?

Thanks in advance to the Hive Mind.

 

[mabrungard]

Definitely NO with regard to the blank slate (tabula rasa). Activated carbon doesn't appreciably change the water's ionic content. You'll have the full ionic content. Depending on your water supply, that could still mean that the water is useable for brewing, but most brewing is going to need some acid added to get the pH into a proper range.

If you know what your water profile is, you are far better off by pre-emptively treating the water to hopefully produce a desirable mash pH.

 

[beerisyummy]

Definitely NO with regard to the blank slate (tabula rasa). Activated carbon doesn't appreciably change the water's ionic content. You'll have the full ionic content. Depending on your water supply, that could still mean that the water is useable for brewing, but most brewing is going to need some acid added to get the pH into a proper range.

If you know what your water profile is, you are far better off by pre-emptively treating the water to hopefully produce a desirable mash pH.

Ah ha. Then I should go ahead and try to obtain a water analysis from my utility?

 

[myndflyte]

Ah ha. Then I should go ahead and try to obtain a water analysis from my utility?

Check online as they may post yearly water reports. But that's also a problem in that the water content can change throughout the year. It may be worth calling them and see if they can give you a report, and if so, how often do they do one. You can also send out samples periodically throughout the year to get tested, but that'll cost you money each time. Another option is to just start with distilled or RO water and build your water profile from there.

 

[VTX1300]

My tap water is just nasty. I have not made the investment in an RO system yet so I use all distilled water and build from there. That gives me much better control on my water chemistry. Use one of the online water chemistry calculators like Martin's Bru'n water and they will get you close.