Beer is 90% water. So why do most home brewers treat it like an afterthought? Here's your beginner's guide to water chemistry — and why Burton-on-Trent made IPAs famous.
Here's a fact that blows people's minds: the water in Burton-on-Trent, England — a town most Americans have never heard of — is directly responsible for why IPAs taste the way they do.
Burton's water is naturally high in calcium sulfate (gypsum). This mineral profile accentuates hop bitterness and dryness in a way that became the defining characteristic of British pale ales and IPAs. When British brewers figured this out in the 1800s, they started "Burtonizing" their water everywhere else. The practice spread worldwide.
Beer is 90-95% water. Treating it like an afterthought is like a chef ignoring their cooking oil.
You don't need a chemistry degree. You need to understand six ions and what they do.
The workhorse mineral. Calcium aids yeast health, enzyme activity, and protein coagulation. Most water profiles target 50-150 ppm. Too low and fermentation suffers. Magnesium can substitute in small amounts but tastes bitter at high levels.
A yeast nutrient in small doses, harsh and laxative in large ones. Keep it under 30 ppm. Your water probably already has some.
Enhances malt sweetness and body at low levels (under 150 ppm). At high levels it tastes salty and clashes with hops. Used deliberately in some British ales for a soft, full mouthfeel.
The malt-enhancer. Chloride rounds out mouthfeel and emphasizes sweetness. Higher chloride-to-sulfate ratios make beer taste rounder, fuller, and more malt-forward. Great for stouts, porters, and English ales.
The hop-enhancer. Sulfate accentuates bitterness and creates a drier, crisper finish. Higher sulfate-to-chloride ratios emphasize hop character. Essential for West Coast IPAs. Burton water has up to 800 ppm — that's extreme but effective.
The pH buffer. High alkalinity raises mash pH, which can make beer taste harsh and astringent. Dark malts counteract this, which is why Dublin's alkaline water (from limestone geology) is perfect for Guinness-style stouts but terrible for pale ales.
| City | Character | Famous For | |------|-----------|------------| | Burton-on-Trent | High sulfate, calcium | IPAs, pale ales | | Dublin | High alkalinity | Dry stouts (Guinness) | | Pilsen | Ultra-soft, nearly pure | Czech lagers, Pilsners | | Munich | Moderate alkalinity, calcium | Lagers, Märzens | | London | Moderate, soft | Porters, bitter ales |
This isn't a coincidence. Brewing traditions grew around available water.
Get a water report from your municipal supplier (usually free online) or use an inexpensive water testing kit. If you brew with reverse osmosis (RO) or distilled water, you start with a blank slate — which is actually ideal because you have full control.
Match your water to your beer style. Building a hazy IPA? Emphasize chloride. West Coast IPA? Raise sulfate. Dark lager? Moderate everything and watch your alkalinity.
These are available at any homebrew shop and cost almost nothing:
A free tool like Brewfather or Bru'n Water will calculate exact additions for your volume.
Mash pH is arguably more important than mineral content. The ideal mash pH for most beers is 5.2–5.4. At this range, enzymes convert starches to sugars efficiently and extraction is optimal.
Too high (above 5.5): astringent, harsh, husky flavors Too low (below 5.0): thin, overly acidic, yeast stress
Buy a decent pH meter. A $30 meter beats a $3 strip every time for accuracy.
When I first started adjusting water, I was skeptical. My beers were fine. Were they really going to taste noticeably different?
Yes. The difference was immediately obvious. My hazy IPA went from "pretty good" to "what is happening, this is excellent." The mouthfeel became softer and rounder. The hop aroma was more vibrant. The beer cleared faster in the fermenter.
I've since never brewed with unadjusted tap water again.
If this feels overwhelming, start here:
The difference will convince you faster than any article.
Looking for brewing supplies? We recommend MoreBeer for minerals, meters, and gear. Some links may be affiliate links — see our disclosure.
