Bend’s Water Quality

In the journalism world. a writer needs to have a stock of “Evergreen” stories on hand. Evergreen stories are just as they sound—ideas that can be used any time of the year whenever there isn’t much going on otherwise. In the beer industry, there are always a couple of Evergreen stories that (thanks to the industry) are ever-changing. My idea for an evergreen story was about Bend’s water quality. People always talk about it—how it was the reason that beer hit so big out here—but never explained why. Did we have signature water like Burton on Trent? I did some digging and found out a lot. According to beer blogs and books, water quality reports can be acquired just by asking your local water department. This is partially true, yes. But I had to dig around to find the right numbers. After three phone call re-routs, I finally landed on the right guy: Steve Prazak of the City of Bend water quality department. He led me to a website that broke down every possible mineral in our city’s water. Here are the ones important to brewing:

Calcium: 7.8 ppm

Magnesium: 6.7 ppm

Total Alkalinity: 70 ppm

Sodium: 10.67 ppm

Chloride: 2.6 ppm

Sulfate: 1.12 ppm

So, as a beer journalist who was in over his head, I took these numbers to specialist and co-author of Water: A Comprehensive Guide for Brewers John Palmer.

I expected a couple of things from him. First off, I expected a delayed response. Second, I expected a shorter answer from an assumedly busy guy.

I didn’t get either.

John gave me an incredibly in-depth report about the city of Bend’s water, which he described as “very close to distilled.”

“You can brew pretty much any style of beer with this water,” he wrote. “All you have to do is add the appropriate calcium salt to boost the calcium levels to 50-150 ppm, depending on style.”

Palmer continued to say that with hoppier styles, brewers should add calcium sulfate, AKA gypsum, to play into bitterness’ hand. If you’re trying to highlight malt, look toward adding calcium chloride.

What I really gathered from writing this story was that Bend is the perfect canvas for really any style because the brewers in the city, instead of filtering, simply have to add the minerals in the amounts they want. Problem solved.

Here’s the entire email that Palmer wrote back to me:

The water is very close to distilled except for the Total Alkalinity. 70 is Medium. Everything else is considered very low. You can brew pretty much any style of beer with this water, all you have to do is add the appropriate calcium salt to boost the calcium levels to 50-150 ppm, depending on style. For hoppier styles (pale ale, etc) you would use calcium sulfate (gypsum) to add sulfate to boost the hop bitterness and dry out the character of the beer somewhat. For maltier styles (oktoberfest, etc) you would use calcium chloride to round out the malty flavor.  Now then, Residual Alkalinity is the most important water parameter for brewers, because this number gives you a good idea of how your water chemistry will affect your mash pH, which affects your starch conversion, wort pH, boil mechanics (hop isomerization, trub formation, melanoidin formation, etc) and eventually your beer flavor. Beer pH affects how the beer’s flavors are expressed to the palate. Think of it as a bell curve, with the proper pH (depends on style/recipe/trialanderror) giving the peak of all the flavors of the beer; more acidic pH attenuating the flavors, and more basic pH broadening and dulling the flavors. Proper beer pH will be a balance of brightness/richness/complexity without dullness. Basically, positive RA will raise mash pH from the distilled water value, negative RA will lower mash pH from the distilled water value. Typical base malt mash pH is 5.8. The mash pH target for all beers, regardless of style, is 5.2-5.6, measured at room temperature. Brewers are trying to guide their mash pH to that range by a combination of grist bill and water chemistry. Residual Alkalinity =  Total Alkalinity – (Ca/1.4 + Mg/1.7) = 60 ppm as CaCO3 for Bend OR.  (as CaCO3 is a water unit of chemical reaction equivalence, I can explain if you want, but it will take half a page) A value of 60-75 RA as CaCO3 will tend to raise or lower the mash pH by 0.1 pH unit. So, for Bend, this water would raise the pH by 0.1, from 5.8 to roughly 5.9. And a higher mash pH tends to give the beer a coarser bitterness, and a general dulling of the malt flavor (the malt flavor won’t be “bright”) Now, on the other hand, 0.1 pH is not a big deal. The specialty malts (colored malts, caramel, roast etc.) have acidity from the melanoidins that form during kilning and roasting. Depending on your beer style/color, the specialty malt additions to the grist will easily counterattack the RA of this water.  AND, you really need a minimum of 50 Calcium for any style for good brewing biochemistry performance, so if you add 1 gram of gypsum per gallon of brewing water, you will get 67 ppm of Ca and 147 ppm of Sulfate, giving you a water chemistry of: 70 Ca 7  Mg 70 Total Alk 148 Sulfate 3 Chloride 11 Sodium RA = 16 ppm as CaCO3, which is in the ballpark of near zero for our purposes.

For IPAs, you would probably double it to 2 grams per gallon, giving 130 Ca, 296 sulfate, and an RA of -28. If you used calcium chloride for maltier lager styles such as Octoberfest, or Cream Ale, 1 gram per gallon would be 72 Ca and 130 Chloride, giving

80 Ca 7  Mg 70 Total Alk 1 Sulfate 130 Chloride 11 Sodium RA = 9 ppm as CaCO3 (again near zero)

This would be a good water for any lager style really. You would not want to double this chloride concentration because the beer tends to get minerally above 150 (depending on personal taste). But you could do 1 gram gypsum and 1 gram calcium chloride and get 

142 Ca 7  Mg 70 Total Alk 148 Sulfate 130 Chloride 11 Sodium RA = -35 ppm as CaCO3

This water would have a more balanced Sulfate to Chloride ratio, being balanced between hoppy-dry and malty-round. Good for Amber ales.

Boom. I mean, I didn’t want to read the water book (too much chemistry for my mathematically stunted brain) but I do now.

Thanks to Mr. Palmer for taking time out of his day to help out and send a young journalist an email. Also, thanks for helping me understand about the former mind-boggling water chemistry.

Advertisements

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s