Adding CACL and Gypsum to mash or kettle?

[djbradle]

I've been adding these specific salts to the mash maybe but I'm thinking it's best to keep them for the boil and sparge water? Do they get absorbed by the grain in the mash precluding them from the boil?

 

[TimmyWit]

They will make their way to the boil. But, the most important thing is to determine how they will affect your mash ph. For example, if you are doing a brew with a lot of crystal malt, your mash ph may already be on target. In this case, you would want to reserve your additions for the boil as to not drive the mash ph too low. There are plenty of free calculators to help you estimate where your mash ph will be based on your grain bill and mineral additions. I use brun water.

 

[djbradle]

Thanks for the quick response!
I didn't think calcium chloride and calcium sulphate had any effect on mash ph.....in any case that's what I remember hearing.

 

[TimmyWit]

I only use gypsum and CaCl. They both lower PH. In Brun Water, based on a 4.5 gallon mash, 2.3 grams CaCl will lower PH by .1. Gypsum lowers it as well. Do you know your current water profile? I recommend downloading Brun Water; play around with it a bit to get an idea of what your mineral additions are doing to your mash PH. The gentleman who created it is an active member on HBT as well.

https://sites.google.com/site/brunwater/

I build from RO water and I measure my PH throughout the mash. I have found the Brun Water estimates are reasonably accurate.

 

[ajdelange]

Thanks for the quick response!
I didn't think calcium chloride and calcium sulphate had any effect on mash ph.....in any case that's what I remember hearing.

Each milliequivalent of calcium (20 mg) releases approximately 1/3.5 mEq of protons to knockout and somewhat less than that to the mash. The buffering of mash is generally around -40 mEq/pH•kg so it is pretty easy to roughly estimate the pH shift from the addition of x grams of calcium per liter as
-((x/20)*liters_water/3.5)/kg_malt/40

 

[mabrungard]

Some calcium is 'tied up' in the mash, but that is a good thing. An important result is the precipitation of oxalate from the wort which helps reduce beerstone formation in the brewery. I recommend using mashing water with at least 40 ppm Ca for that reason. The acidification response outlined by AJ is also a good reason to add calcium to the mash.

 

[ajdelange]

An important result is the precipitation of oxalate from the wort which helps reduce beerstone formation in the brewery.

And the brewer!

 

[mabrungard]

That could be an important feature for someone with kidney stones!

 

[TimmyWit]

Some calcium is 'tied up' in the mash, but that is a good thing. An important result is the precipitation of oxalate from the wort which helps reduce beerstone formation in the brewery. I recommend using mashing water with at least 40 ppm Ca for that reason. The acidification response outlined by AJ is also a good reason to add calcium to the mash.

This is good to know. I did a Red Rye IPA last night and reserved all my additions for the boil. Mash PH ended up at 5.37. Based on this info, should I have added some Calcium Chloride and then countered it with some Baking Soda to balance mash PH? I see that chalk raises it as well but I think I remember reading that chalk does not dissolve well.

I'm fairly new at building water. Your spreadsheet certainly helps!

 

[mabrungard]

A few hundredths are not really worth chasing. You ended up close enough. The calcium chloride would actually be counterproductive since it would lower pH. You are correct to stay away from chalk. It's not a reliable tool for water adjustment.

 

[TimmyWit]

A few hundredths are not really worth chasing. You ended up close enough. The calcium chloride would actually be counterproductive since it would lower pH. You are correct to stay away from chalk. It's not a reliable tool for water adjustment.

I was happy with the 5.37 PH. But, since I am using RO and I didn't add any minerals to the mash (<40ppm calcium), I was wondering if it would be beneficial to add the calcium chloride to reduce beerstone formation as you mentioned before. Consequently, I would need to add baking soda to get my PH back in the desired range. Does that sound right?

 

[ajdelange]

See #5. The calcium doesn't have that much effect. Remember that the Kolbach number (1/3.5) is for knockout. In the mash you'll see less than that (half?).

 

[djbradle]

Thanks for the info guys...I added my salts right to the mash on my current brew not worrying about losing the effect. Just rolling with it and not paying attention to my ph at this point. My beers have been coming out very very tasty for the last couple years. Maybe when I brew my first RIS or DIPA I'll have to pay more attention but all my Belgian ales are spot on to where I don't buy anything commercial much anymore.