Add gypsum to sparge, or directly to kettle?

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scone

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I can't seem to find the answer to this although I feel like it must have been asked. I'm using the bru'n water spreadsheet and trying to wrap my mind around the chemistry involved. It is suggesting a bit of sparge water acidification (to the tune of .47 tsp/gallon) given my water chemistry as reported on the city water quality website (http://www.austintexas.gov/sites/default/files/files/Water/WaterQualityReports2012/wqs_2q2012.pdf). This is fine and dandy, but I am also a bit low on calcium, so playing with the Water Adjustment page it looks like I can do 1.0 g/gallon gypsum to compensate (which additionally helps push my predicted mash pH into a good place).

The spreadsheet seems to imply that I should treat my mash AND sparge water with gypsum, but wouldn't this mess with the alkalinity of the sparge water? The Sparge Acidification page doesn't seem to consider my altered water chemistry, only the water chemistry I input on the first page. So my question: should I hold back the gypsum addition from the sparge water and just add it to the kettle? Does it matter?. I'm already adjusting the sparge water using phosphoric acid, so it seems like adding gypsum as well (without knowing its effect on the pH is a bad idea).

In summary, my plan is to:
Use phosphoric acid in the sparge water to hit the right pH
Use gypsum in the mash to adjust mash pH and add calcium to the water
 
I can't seem to find the answer to this although I feel like it must have been asked. I'm using the bru'n water spreadsheet and trying to wrap my mind around the chemistry involved. It is suggesting a bit of sparge water acidification (to the tune of .47 tsp/gallon) given my water chemistry as reported on the city water quality website (http://www.austintexas.gov/sites/default/files/files/Water/WaterQualityReports2012/wqs_2q2012.pdf). This is fine and dandy, but I am also a bit low on calcium, so playing with the Water Adjustment page it looks like I can do 1.0 g/gallon gypsum to compensate (which additionally helps push my predicted mash pH into a good place).

The spreadsheet seems to imply that I should treat my mash AND sparge water with gypsum, but wouldn't this mess with the alkalinity of the sparge water? The Sparge Acidification page doesn't seem to consider my altered water chemistry, only the water chemistry I input on the first page. So my question: should I hold back the gypsum addition from the sparge water and just add it to the kettle? Does it matter?. I'm already adjusting the sparge water using phosphoric acid, so it seems like adding gypsum as well (without knowing its effect on the pH is a bad idea).

In summary, my plan is to:
Use phosphoric acid in the sparge water to hit the right pH
Use gypsum in the mash to adjust mash pH and add calcium to the water

Go ahead and add the gypsum. It doesn't add alkalinity.
 
And depending on what your sulfate level is already, you might want to skip the gypsum and add a tsp of Calcium Chloride per 5 gallon of water to be treated.

Most of the time, accentuating the Malt profile results in a more enjoyable beer and that's what CaCL does (but remember more is not always better). Most beers need very little gypsum and that's only in really hop-accentuated IPAs, but that's just my two cents. This advice is along the lines of what Aj recommends and I've had a lot of success following his advice.
 
If your goal is to produce a certain level of calcium and sulfate in your finished wort, then adding a dose of gypsum to account for the sparge water volume is required. You don't have to add that gypsum to the sparge water, but can add that dose directly to the kettle if you prefer. As pointed out above, gypsum does not add alkalinity, so its OK to add to the sparge water.

As you noted, adding the gypsum to the mash is helpful for helping lower the mash pH in addition to its other calcium effects. Do add it there.

By the way, that seems like a lot of acid if it was 88% lactic. But I see that you are using phosphoric and the strength is not denoted. Given that Austin water is lime softened and the alkalinity is moderate, I'm assuming you are using 10% phosphoric and not 85%. If that is the case, then that quantity of acid in the sparging water is not surprising.
 
My water has 47.3 ppm sulfate to 48 ppm chloride (after treatment with kmeta to remove chloramines, assuming the additions suggested on the bru'n water homepage). I guess maybe I should do a 1:1 gypsum and CaCl addition instead of pure gypsum to keep them balanced? Which begs the question, can I also put CaCl in the sparge water without worrying about it's effect on sparge pH?
 
If your goal is to produce a certain level of calcium and sulfate in your finished wort, then adding a dose of gypsum to account for the sparge water volume is required. You don't have to add that gypsum to the sparge water, but can add that dose directly to the kettle if you prefer. As pointed out above, gypsum does not add alkalinity, so its OK to add to the sparge water.

As you noted, adding the gypsum to the mash is helpful for helping lower the mash pH in addition to its other calcium effects. Do add it there.

By the way, that seems like a lot of acid if it was 88% lactic. But I see that you are using phosphoric and the strength is not denoted. Given that Austin water is lime softened and the alkalinity is moderate, I'm assuming you are using 10% phosphoric and not 85%. If that is the case, then that quantity of acid in the sparging water is not surprising.

Thanks! And yes, I should have specified. I'm using 10% phosphoric acid.
 
My water has 47.3 ppm sulfate to 48 ppm chloride (after treatment with kmeta to remove chloramines, assuming the additions suggested on the bru'n water homepage). I guess maybe I should do a 1:1 gypsum and CaCl addition instead of pure gypsum to keep them balanced? Which begs the question, can I also put CaCl in the sparge water without worrying about it's effect on sparge pH?

I would go with only the CaCL since your sulfate level is already close to 50ppm. And most people treat both mash and sparge water together, so no need to treat separately
 
I would go with only the CaCL since your sulfate level is already close to 50ppm. And most people treat both mash and sparge water together, so no need to treat separately

Unfortunately unless I dilute with distilled water, the only way for me to reach 40+ppm Ca is to use both gypsum and calcium chloride (if I try to just use CaCl2 my chloride goes above 100ppm, which the spreadsheet tells me is baaad.) :D

If I do .3 g./gal. gypsum and .4 g./gal. CaCl2 I get
Ca Ma Na sulfate chloride
58.2 18.0 24.4 91.5 99.0

with a comfy buffer on Ca levels, but pushing the upper limits on what's recommended for sulfate and chloride both. Hmm, maybe I should consider diluting with distilled water, it's just kind of expensive! :mad:

By the way, mabrungard, thanks for making the spreadsheet. It's awesome! :tank:
 
I'm actually making an IPA with the same water, today, so I'm going with 4g gypsum, split between the mash and sparge. It gets me into the calcium range I'm looking for, without throwing the ph out of whack, and it seems like pushing the sulfate just over 100ppm is actually preferred for this style. Of course, I'm just playing with B'run Water, too (MAJOR thanks, mabrungard!), so we'll chalk it up to a learning experience, either way...

So I guess the open question is: Isn't this question greatly dependent on what style you're planning on making?
 
I'm actually making an IPA with the same water, today, so I'm going with 4g gypsum, split between the mash and sparge. It gets me into the calcium range I'm looking for, without throwing the ph out of whack, and it seems like pushing the sulfate just over 100ppm is actually preferred for this style. Of course, I'm just playing with B'run Water, too (MAJOR thanks, mabrungard!), so we'll chalk it up to a learning experience, either way...

So I guess the open question is: Isn't this question greatly dependent on what style you're planning on making?

I'm thoroughly unqualified to answer your question given that I just started messing with my water myself. :D But yeah, I would think it is, but then again I've also read that some people prefer a slightly "maltier/sweeter" sulfate:chloride ratio even for their very hoppy beers so YMMV. Some of the "classic" brewing water profiles seem pretty extreme in comparison to the recommendations in Bru'n Water, and that's another point of confusion for me.

It seems to me that aside from a low Ca content, Austin water seems pretty decent for brewing. Did you check out that thread I linked above? Apparently a number of the pro brewers in the area use only phosphoric acid and nothing else. I don't know if it's just for the sparge, or to treat the whole water content, but I suspect that some may leave the acid treatment out of the mash water for very roasty/dark beers.
 
A person can always treat the water with CaCL and add Gypsum to the glass to see if the like the flavor Gypsum adds. Most people tend to prefer a maltier beer over one too bitter from large additions of Gypsum.
 
When making gypsum or calcium chloride additions directly to the kettle, is there a better time? Early or late in the boil, or does it matter?
 
It seems to me that aside from a low Ca content, Austin water seems pretty decent for brewing. Did you check out that thread I linked above? Apparently a number of the pro brewers in the area use only phosphoric acid and nothing else. I don't know if it's just for the sparge, or to treat the whole water content, but I suspect that some may leave the acid treatment out of the mash water for very roasty/dark beers.

Yeah, I've actually been taking a look at the notes on local brewers fermentation tanks, and it confirms that thread. Most of them just use phosphoric. South Austin adds gypsum and chalk, but that's the only thing I've seen other than a straight acid addition.

For what it's worth, my IPA mash last week ended up in the mid- to high- fives (hard to be exact with litmus paper), and my efficiency definitely suffered (64%, lowest ever). Turns out gypsum isn't really a magic bullet for Ca and pH for Austin water, at least not for lighter beers (5.5 SRM). In a way, it's a relief, though. At least I'm getting a similar experience to everyone else. We'll see what gypsum does for the hop-forward flavor, but it looks like I'll be working with a phosphoric addition, going forward.
 
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