Help with Residual Alkalinity, Mash PH & Acidulated Malt

[ProperTing]

My tap water is very soft like Pilsn. Pretty much RO water without the troubles. I recently brewed a English Summer Ale made up of mostly base malt (MO, Pilsner and Wheat) with a very tiny bit of caramel 120L for colour. Due to the alkalinity of the malts, I had to add 5oz of acidulated malt to get my PH where it should be.. yet this dropped the RA very very low at -250. Adding ions to raise the alkalinity was no use as I end up having to add more acid to get the PH down. A downward spiral! What should I do here for situations like these, where your RA for the style should be in the -50-0 range, yet it seems to be... unachievable? Should I even worry about it and what are the effects of having the RA so low with these malts?

 

[Pie_Man]

I am not a water expert, but I would not worry about RA too much, your mash pH is what matters.

 

[zwiller]

I don't pay attention to RA and just focus on pH. What was your pH target? I am confused why the need for so much acid malt. I would think with as nice as water as you have a small gypsum addition would have gotten you within range.

 

[ajdelange]

RA is used to compare water supplies. Beyond that it has little utility in brewing though many of the spreadsheets, articles and even books try to make it do what it was never intended to do with the result that people get confused as is the case here. Do not worry about RA. Worry about mash pH. With mostly base malt and a small amount of colored malt you should only need about 3% sauermalz. Yes, sauermalz contains acid and if you blindly plug that acid into a spreadsheet or calculator or even the RA formula the RA will go negative, as will the alkalinity, but that is not of concern.

The fact that you are talking about alkalinity of malts suggests that you are reading something somewhere (possibly here - i.e. Brewing Science) that is pretty advanced perhaps before you are ready for it. To start out just add some calcium chloride and some sauermalz and check the mash pH. If it is too low use less sauermalz (make test mashes).

 

[ProperTing]

I've read some of your findings, in fact, in the water brewing elements book! No matter what I added (in regards to calcium chloride, calcium sulfate and magnesium sulfate) it didn't bring the ph down to where it needed to be, while keeping my ions in tolerable ranges.. resulting in a need to add the acid malt (2%) which knocked down my RA way lower than what was outlined in the book or anywhere I could find on the internet. Thanks for clearing this up!

Thanks for all your hard work and contributions!

 

[SpeedYellow]

I've read some of your findings, in fact, in the water brewing elements book! No matter what I added (in regards to calcium chloride, calcium sulfate and magnesium sulfate) it didn't bring the ph down to where it needed to be, while keeping my ions in tolerable ranges.. resulting in a need to add the acid malt (2%) which knocked down my RA way lower than what was outlined in the book or anywhere I could find on the internet. Thanks for clearing this up!

Thanks for all your hard work and contributions!

Seems you got sucked into the outdated approach. The idea used to be: keep adding minerals until your RA was ok. But that's a big fail because using minerals to chase pH won't work, and can negatively affect flavor. Today's thinking is ignore RA, use acids to deal with pH, and only add minerals for flavor needs.

 

[ajdelange]

I tried to nudge John away from too much emphasis on RA but he is still thinks of it as being at the core of brewing water chemistry.

 

[ProperTing]

I don't pay attention to RA and just focus on pH. What was your pH target? I am confused why the need for so much acid malt. I would think with as nice as water as you have a small gypsum addition would have gotten you within range.

11 gallon batch.

 

[zwiller]

11 gallon batch.

Touche'

I hit the sulfate levels a bit higher (via gypsum) than most spreadsheets want you to good effect in my ales. Lagers are a less is more thing...