Mash pH over 6.0

[bruderbier]

I'm new to all grain...6 brews under my belt...and I hadn't run into this problem before.

After adjusting my strike water using some calculations based on Palmer, I ended up with a high mash pH at mash temperatures around 6.1. I was brewing an oatmeal stout and added too much bicarbonate to offset the acidic roasted grain.

I realize now that I should not be doing that until after I've determined the actual pH of the mash. Live and learn. I did not know about gypsum to lower the pH either, so I just let it go.

I've been reading and apparently I've extracted tannins with the high pH. Has anyone done this? What in terms of finished product should I expect? Bitterness? Flatness? Undrinkableness?

It's a Christmas beer and it should have had a lot going on with oatmeal, molasses, and spices. I've learned in past that spiced beers need time to mellow. Should I start over to have a good beer for Christmas parties?

I'd like to RDWHAHB, but as I'm intending to serve this to other people, I'd like to have a good product.

 

[TheMan]

How did you measure your PH? Most PH meters require the wort to be room temperature to read accurately.

As for the finished product, each recipe will be affected differently. It might be a bit astringent. Or you may not notice it since it's a stout.

 

[bruderbier]

I used precision labs test strips dipped directly in the mash after 15 minutes. It's a rough gauge, but the color was definitely bordering on purple.

Thanks. It won't be my first astringent beer.

 

[Yooper]

Generally, you never need to add bicarb to a mash. Most often, people are struggling with mash pH that is too high, not too low. Even in a stout, I doubt that your mash pH would have been too low.

I wouldn't do anything to the water without knowing the exact makeup of the water, and then using a good spreadsheet (I like EZ water, but I know many people love Brunwater.) And then checking the pH before doing anything radical, like adding bicarb!

 

[mabrungard]

Unless you are dealing with distilled water or RO water as a starting point, you probably don't have to add alkalinity to the mash water. Palmer's nomograph is terribly flawed and tends to produce the result you observed.

Hopefully you did not add alkalinity to the sparge water. It must have low alkalinity to avoid tannin extraction. If anything, sparge water is more typically acidified to reduce alkalinity.

If you want to learn a bit more about brewing water chemistry, I recommend that you download Bru'n Water and read the Water Knowledge section. It will help correct some of the errors that other print and internet sources have instilled.