Sanity check on water for my APA

I'm about to embark on my second AG batch and finally decided to suck it up and tackle the Bru'n Water sheet. My goals were to reach an RA that fell within the appropriate range for an APA (8.2 SRM) and an appropriate SO4/Cl ratio that favors the bitterness/hops.

Water Input:


Sparge Acidification:


Water Profile Adjustment:


Mash Acidification:


The two additions I ended up with are Gypsum (~9grams total) and Calcium Chloride (2.2 grams total).

1) Do the adjusted water values look good?

2) How important is the acid addition to the Sparge water?

TIA!

Looks good. For a hoppy ale, 1g gypsum per gallon of water is not excessive. But, the calcium concentration that you're pushing with that gypsum level is tending to push the RA down and taking the mash pH with it. I'd back off slightly to aim for a 5.4 pH.

The acid addition for the sparge water is critical to avoid tannin extraction and pushing the pH of the wort in the kettle too high. The alkalinity of the raw water is almost 100 ppm. It needs to be well under 50 ppm to avoid tannin extraction. I recommend a target alkalinity of about 25 ppm to assure no tannin issues. Don't skip acidification of the sparge water with this tap water.

Enjoy!

Thanks for the reply.

mabrungard said:

But, the calcium concentration that you're pushing with that gypsum level is tending to push the RA down and taking the mash pH with it. I'd back off slightly to aim for a 5.4 pH.

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Where would I find the resultant pH? On the Mash Acidification sheet?

I reduced the Gypsum down to .5 gram/gal - half of my initial amount - and the pH listed on the Mash Acidification sheet didn't move at all (RA went from 12 to 34). I figure I'm looking at the wrong area or perhaps can disregard and concentrate more on the RA.

mabrungard said:

The acid addition for the sparge water is critical to avoid tannin extraction and pushing the pH of the wort in the kettle too high. The alkalinity of the raw water is almost 100 ppm. It needs to be well under 50 ppm to avoid tannin extraction. I recommend a target alkalinity of about 25 ppm to assure no tannin issues. Don't skip acidification of the sparge water with this tap water.!

Click to expand...

Thanks you for clarifying this but don't the the Sparge additions effect pH as well? For example - in the screen shots above - I'm adding ~5 grams of Gypsum and 1.2 grams of CaCl2 to the Sparge. Don't those work to drop the pH or are they already taken into consideration on the Sparge Acidification sheet?

(I'm assuming that you add the additions as you heat the sparge water - please let me know if I'm wrong )

You are correct, the resulting mash pH is shown on the Mash Acidification sheet.

Since the tap water only has moderate alkalinity and the strong addition of gypsum and calcium chloride are pushing the RA down a little too far, a change is needed. A technique to avoid a lower than desired mash pH is to hold all or a portion of those minerals from the mash and add them directly to the kettle. You want certain levels of sulfate and chloride in your water to meet your beer taste goals. If the mash pH is going to be too low, dial back those mineral additions until a more acceptable mash pH of about 5.4 is predicted. Add only that amount of the minerals to the mash. After the wort is run off into the kettle, add the remainder of the mineral amounts to meet your chloride and sulfate goals.

Since sparge water is not part of the main mash, its does not participate in the phytin reaction that is central to the RA effect of adding calcium or magnesium to the mash. Adding gypsum or calcium chloride does not alter the pH of the sparge water. Only the addition of an acid to the sparge water to reduce alkalinity is what matters.

You should typically add minerals and acid to the water prior to or during heating. Everything is more soluble at lower temperature.

mabrungard said:

Since the tap water only has moderate alkalinity and the strong addition of gypsum and calcium chloride are pushing the RA down a little too far, a change is needed.

Click to expand...

To make sure I'm understanding this correctly, the RA of 12 would be considered too low for this style of beer (APA, SRM~8)?

mabrungard said:

A technique to avoid a lower than desired mash pH is to hold all or a portion of those minerals from the mash and add them directly to the kettle.

Click to expand...

I've seen 'kettle' mentioned a few times and wasn't sure what it meant. This is basically the final wort prior to boil?

mabrungard said:

Since sparge water is not part of the main mash, its does not participate in the phytin reaction that is central to the RA effect of adding calcium or magnesium to the mash. Adding gypsum or calcium chloride does not alter the pH of the sparge water. Only the addition of an acid to the sparge water to reduce alkalinity is what matters.

Click to expand...

In other words, I could hold off adding any of the salts to the Sparge and add them to the 'kettle' prior to boiling the wort, right?

Just want to say thanks again - I've learned a tremendous amount in a pretty short amount of time.

dotsoncs said:

To make sure I'm understanding this correctly, the RA of 12 would be considered too low for this style of beer (APA, SRM~8)?



I've seen 'kettle' mentioned a few times and wasn't sure what it meant. This is basically the final wort prior to boil?



In other words, I could hold off adding any of the salts to the Sparge and add them to the 'kettle' prior to boiling the wort, right?

Just want to say thanks again - I've learned a tremendous amount in a pretty short amount of time.

Click to expand...

RA is not really the target, pH is. Apparently for the grist you are using, the RA of this water is too low to enable the mash to reach the targeted pH.

Yes, kettle refers to adding the minerals to the kettle prior to boiling the wort.

Yes, for any minerals that need to be reserved from the mash or any minerals for the sparging water can be added to the kettle prior to boiling.

Enjoy!