Home Brew Forums > Home Brewing Beer > Brew Science > Add gypsum to sparge, or directly to kettle?
Reply
 
Thread Tools
Old 09-13-2012, 05:07 PM   #1
scone
Feedback Score: 0 reviews
Recipes 
 
Join Date: Oct 2009
Location: Austin, TX
Posts: 291
Likes Given: 1

Default Add gypsum to sparge, or directly to kettle?

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/def...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
scone is online now
 
Reply With Quote
Old 09-13-2012, 05:22 PM   #2
afr0byte
Feedback Score: 0 reviews
Recipes 
 
Join Date: Aug 2010
Location: Vermont
Posts: 1,435
Liked 74 Times on 62 Posts
Likes Given: 49

Default

Quote:
Originally Posted by scone View Post
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/def...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.
afr0byte is offline
 
Reply With Quote
Old 09-13-2012, 05:26 PM   #3
scone
Feedback Score: 0 reviews
Recipes 
 
Join Date: Oct 2009
Location: Austin, TX
Posts: 291
Likes Given: 1

Default

Quote:
Originally Posted by afr0byte View Post
Go ahead and add the gypsum. It doesn't add alkalinity.
Sweet. Thanks afr0byte.
scone is online now
 
Reply With Quote
Old 09-13-2012, 05:40 PM   #4
helibrewer
HBT_SUPPORTER.png
Feedback Score: 1 reviews
 
helibrewer's Avatar
Recipes 
 
Join Date: Nov 2011
Location: Santa Rosa, CA
Posts: 3,680
Liked 290 Times on 247 Posts
Likes Given: 77

Default

It's chalk you want to avoid in the sparge and mash.
__________________
Something is always fermenting....
"It's Bahl Hornin'"

Primary:
Brite Tank/Lagering:
Kegged: Sour Saison, Pale Ale, Aggie Ale, Firestone DBA, De Koninck Blonde
Bottled: Belgian Quad (Grand Reserve), Derangement (Belgian Dark Strong)
On Deck: Pliny the Younger
helibrewer is offline
 
Reply With Quote
Old 09-13-2012, 05:46 PM   #5
cooper
Feedback Score: 0 reviews
Recipes 
 
Join Date: Dec 2009
Location: New Baden, IL
Posts: 353
Liked 10 Times on 8 Posts

Default

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.
cooper is offline
 
Reply With Quote
Old 09-13-2012, 05:49 PM   #6
mabrungard
HBT_LIFETIMESUPPORTER.png
Feedback Score: 0 reviews
 
mabrungard's Avatar
Recipes 
 
Join Date: Feb 2011
Location: Carmel, IN
Posts: 3,189
Liked 282 Times on 236 Posts
Likes Given: 29

Default

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.
__________________
Martin B
Carmel, IN
BJCP National
Foam Blowers of Indiana (FBI)

Brewing Water Information at:
https://sites.google.com/site/brunwater/

Like Bru'n Water on Facebook for occasional discussions on brewing water and Bru'n Water
https://www.facebook.com/pages/Brun-...?ref=bookmarks
mabrungard is offline
trapae Likes This 
Reply With Quote
Old 09-13-2012, 05:53 PM   #7
scone
Feedback Score: 0 reviews
Recipes 
 
Join Date: Oct 2009
Location: Austin, TX
Posts: 291
Likes Given: 1

Default

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?
scone is online now
 
Reply With Quote
Old 09-13-2012, 05:54 PM   #8
scone
Feedback Score: 0 reviews
Recipes 
 
Join Date: Oct 2009
Location: Austin, TX
Posts: 291
Likes Given: 1

Default

Quote:
Originally Posted by mabrungard View Post
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.
scone is online now
 
Reply With Quote
Old 09-13-2012, 06:45 PM   #9
cooper
Feedback Score: 0 reviews
Recipes 
 
Join Date: Dec 2009
Location: New Baden, IL
Posts: 353
Liked 10 Times on 8 Posts

Default

Quote:
Originally Posted by scone View Post
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
cooper is offline
philology Likes This 
Reply With Quote
Old 09-13-2012, 11:02 PM   #10
scone
Feedback Score: 0 reviews
Recipes 
 
Join Date: Oct 2009
Location: Austin, TX
Posts: 291
Likes Given: 1

Default

Quote:
Originally Posted by cooper View Post
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.)

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!

By the way, mabrungard, thanks for making the spreadsheet. It's awesome!
scone is online now
 
Reply With Quote
Reply


Thread Tools


Similar Threads
Thread Thread Starter Forum Replies Last Post
Gypsum bosox Brew Science 11 01-15-2013 02:43 PM
gypsum zrule Brew Science 2 06-08-2012 09:15 PM
Five Star 5.2 plus Gypsum Fletch78 Brew Science 17 11-13-2010 07:03 PM
K-Meta + Gypsum Fletch78 Brew Science 5 11-06-2010 04:53 PM
Gypsum in the boil? JLem Brew Science 4 03-09-2010 12:50 AM


Forum Jump

Newest Threads

LATEST SPONSOR DEALS