Why Your Water Matters as Much as Your Beans

There's a conversation we have fairly often here at Yugen, usually when someone tells us their V60 tastes great in the shop but flat at home. They've bought the same Ethiopian beans, used the same grind setting, followed the same recipe. And yet — something is missing.

Nine times out of ten, the answer is water.

Water Is Not Just a Carrier

We tend to think of water as neutral, the thing that simply carries coffee flavour into the cup. But water is never truly neutral. Every drop that comes out of your tap or bottle contains dissolved minerals, and those minerals actively participate in extraction. They bind to aromatic compounds, pull soluble material from the grounds, and shape what you taste.

The two minerals that matter most are magnesium and calcium. Magnesium is particularly effective at extracting bright, fruit-forward compounds — the kind that make our Colombian bean from Huila sing with its notes of red apple and caramel. Calcium does similar work but tends to favour heavier, more structured flavours. Too much of either, though, and you cross into hard water territory, which leads to over-extraction, bitterness, and scale build-up on your equipment.

The Numbers Worth Knowing

Specialty coffee generally targets a Total Dissolved Solids (TDS) level of around 75–150 mg/L, with the Specialty Coffee Association recommending a sweet spot near 150 mg/L. Tap water in southern Tenerife often runs quite hard — sometimes above 300 mg/L — which is part of why we filter carefully here before every brew.

Bicarbonate (or total alkalinity) is the other variable people overlook. High bicarbonate acts as a buffer that neutralises acidity. That sounds helpful, but in coffee terms it flattens the brightness that makes a naturally processed Ethiopian so extraordinary. When we brew our Ethiopian bean on the Chemex, we want those floral, blueberry notes to ring clearly — and they can't do that if the water is busy dampening the acidity.

What We Do at Yugen

We use filtered water calibrated to sit within that specialty range — low enough in hardness to let our beans express themselves, with just enough mineral content to drive full extraction. When Blend Coffee Roasters delivers a new lot, we sometimes dial our water profile slightly depending on the roast level and origin. A washed Guatemalan from Huehuetenango, for instance, has a structured, chocolatey body that can handle a little more mineral weight than a delicate light-roast natural.

What You Can Do at Home

If your home brew feels hollow or muddy, water is the first thing to question — before you touch your grinder or your recipe.

• Avoid distilled or reverse-osmosis water with no remineralisation. Without minerals, extraction is poor and the cup tastes empty.
• Try a simple filtered jug if your tap water is hard. Even basic carbon filtration reduces chlorine and some hardness.
• Experiment with Third Wave Water or similar mineral packets designed to be added to distilled water — surprisingly effective and inexpensive.

Coffee is mostly water. It only makes sense to pay it the same attention we give the beans.

Next time you're in, ask us what we're brewing that day — and if you want to go deep on extraction science, we're always happy to talk.