Why a Great Cup of Coffee Is Only as Good as the Water You Brew It With

(Yup, that includes the water used from bean to brew, not just what’s in your kettle.)

Hey friends. If you’re reading this, chances are you love coffee, maybe you’re chasing that perfect pour-over, or you’ve got a grinder you brag about, or you’re that person who smells the beans before you even grind them. Me too. But I’m here to drop a truth bomb: 98% (yep, almost all) of your cup is water. And guess what? If that water is off, your coffee is off. Like big time!

1. The Obvious: Coffee = Water + Beans + Magic

• According to the Specialty Coffee Association (SCA), water makes up over 98% of your brewed cup.

  
  

• So yeah, you could have the best beans in the world, but if your water is, say, full of chlorine, odd minerals, or has the personality of dishwater, the beans won’t save you.

2. Water Chemistry Matters (Stay with Me)

a.) Mineral Content & TDS

• Ideal Brewing Water: TDS (Total Dissolved Solids) ~ 75-250 ppm.

  
  

• If minerals are too low (like distilled water): your coffee extraction sucks → flat, hollow cup.

  
  

• If minerals are too high (hard water), you risk over-extraction, bitterness, and weird metallic flavors.

b.) pH & Alkalinity

• SCA Target: pH ~ 7.0 (acceptable ~ 6.5-7.5) for brewing water.

• Too much alkalinity = flavors muted; too acidic = overly sharp.

  
  

c.) Specific Minerals: Calcium & Magnesium

• Calcium helps extract acids → gives brightness and clarity. But too much? Over‐extract.

  
  

• Magnesium helps aromatic extraction, mouthfeel. But again, imbalance = trouble.

So yeah, water isn’t just H₂O. It’s a chemistry experiment that you drink.

3. The "Bean to Cup" Water Story

It’s not just about the kettle water. The story starts much earlier.

a.) Crop & Processing Water

• On average, about 132 liters of water are required to produce one cup of coffee when you include the full production chain (growing + processing + packaging), according to the Water Footprint Network.

  
  

• Some sources estimate around 150 liters (≈ 40 gallons) per cup.

  
  

• For 1 kg of roasted coffee beans: up to 18,925 liters of water in some origin countries.

b.) Why it Matters

• If the water used to process beans is of poor quality (contaminants, mismanaged, etc.), it can impact the bean’s flavor potential before it ever hits your grinder.

  
  

• If your origin is water-scarce, or the processing water is diverted from local communities, there are sustainability & ethics implications. (Yes, being a “responsible caffeinator” matters.)

4. The Practical Stuff: How to Up Your Water Game

Okay, you’re convinced. Now here’s what to do.

✅ Test Your Water

• Use a TDS meter or water hardness strips.

  
  

• Check your local water report (municipal websites often publish data).

  
  

• Compare to SCA targets: TDS ~150 ppm, calcium hardness ~68 mg/L (~4 grains), alkalinity ~40 mg/L.

✅ Filter & Adjust

• At minimum: a carbon filter to remove chlorine and weird flavors.

  
  

• If your water is too soft (near zero minerals): don’t use only distilled; you’ll under-extract. Consider re-mineralizing or adding small mineral packets for coffee.

  
  

• If your water is very hard: consider reverse osmosis + re-mineralizing, or specialist filtration for your coffee machine.

✅ Brew Smarter

• Use water temperature ~ 195°F-205°F (90-96°C) for extraction. (Less good water + wrong temperature = sad coffee.)

  
  

• Stick to the right coffee-to-water ratio (for pour-over: ~1:16 to 1:18 is common). Even epic beans + wrong water = off balance.

✅ Sustainability & Ethics

• Be mindful: your morning latte has a hidden water footprint. The beans you use came from somewhere, processed by someone, using water (sometimes scarce) resources.

  
  

• When possible, support roasters/origins mindful of water stewardship.

6. Final Brew

Look, you’ve got this. You don’t need a whole lab in your kitchen. But just thinking about the water can elevate your coffee from “good” to “wow.”

In short:

• Water quality makes or breaks the flavor potential of your cup.

  
  

• It’s not just about the bean (though beans are awesome). It’s about what’s in the bean + how you unlock it.

  
  

• From crop to cup, water plays a starring role.

  
  

• If your coffee ever tastes “off” and you’ve checked roast, grind, and brew method, consider the water.

  
  

• Your next “perfect cup” might just be a filter change or a water test away.

So go on, treat your water like you treat your beans: with respect, curiosity, and maybe a little obsession. Your cup of coffee deserves it.