Your online store for coffees roasted in Switzerland, inspired by the preparation methods of baristas.
Three-quarters of Swiss households receive hard to very hard water, according to Swiss water dataBut this water makes up more than 98% of your espresso. You can invest in the best organic beans, adjust your grinder to the gram, and master your extraction time, but if the water passing through your coffee puck is high in calcium, the result will always fall short of its potential.
The problem isn't visible. It's noticeable on the palate. A flat, bitter, characterless espresso, whereas the same beans prepared with balanced water would reveal fruity notes and a vibrant acidity. In Switzerland, where limestone soil is the norm, this situation affects the majority of coffee lovers.
Rainwater that seeps into the Swiss soil passes through layers of limestone and gypsum. It becomes enriched with calcium and magnesium, two minerals that define what is known as water hardness. The richer the soil is in limestone, the harder the water.
The problem with espresso is straightforward. Excess calcium acts as a chemical brake on extraction. It binds to the acids and aromatic compounds in the coffee, preventing them from dissolving properly in your cup. The result: a flat, dull, sometimes bitter taste that doesn't reflect the quality of the beans at all. Our baristas see this every day in Café 9|38 coffee shops: from one location to another, the same espresso recipe yields a different profile depending on the local water hardness.
The Specialty Coffee Association recommends a calcium hardness between 51 and 68 mg/L for optimal extraction. In many Swiss municipalities, this value exceeds 150 mg/L, more than double the ideal threshold. The difference between what your coffee could produce and what it actually does is considerable.
Not all minerals are created equal. One study published in the Journal of Agricultural and Food Chemistry Chemist Christopher Hendon has demonstrated that magnesium and calcium extract compounds from coffee in very different ways.
Magnesium promotes fruity and vibrant notes. It binds effectively to the organic acids in coffee, those that give it that pleasant acidity and aromatic complexity that connoisseurs seek. Calcium, on the other hand, tends to bring out the heavier, hollow notes. This isn't necessarily a flaw, but when calcium becomes the dominant component, as in most Swiss waters, the balance shifts.
Your espresso loses finesse but gains heaviness. Subtle aromas disappear behind a mineral veil. This is why two espressos prepared with the same beans, the same machine, and the same settings can taste radically different depending on the water used.
Beyond the taste, hard water physically damages your equipment. When heated water passes through your espresso machine's circuit, calcium precipitates and forms limescale. This whitish deposit accumulates in the boiler, pipes, brewing unit, and pump.
The consequences are gradual but serious. The water temperature at the extraction point becomes unstable because limescale insulates the heating elements. The pressure drops as the pipes narrow. The crema thins, and the body loses its richness. If you notice that your espresso has changed without you having adjusted your settings, limescale is likely the culprit.
With water at over 30°fH, common in cities like Zurich or Lucerne, regular descaling becomes indispensable. To go further, our coffee equipment maintenance guide It details the correct procedures. Without maintenance, repairs cost much more than a filter.
No need to install a complex system. Three accessible solutions allow you to bring your water back into the ideal range recommended by the Specialty Coffee AssociationThis corresponds to a TDS level between 75 and 250 ppm with a calcium hardness of 51 to 68 mg/L. To find out where you stand, hardness test strips are available in drugstores for a few francs: they give you your starting point in a few seconds.
The water filter pitcher This is the simplest solution. Activated carbon models reduce limescale and chlorine. Plan on changing the filter monthly for consistent efficiency. The investment is minimal and the results are immediate.
The filter integrated into the machine It offers dual protection. It softens the water and protects the internal circuit against limescale buildup. It's the ideal solution if you want to forget about the problem: you change the cartridge according to the manufacturer's instructions, and your machine stays clean.
Low-mineral bottled water This also works, provided you check the label. Aim for a TDS around 100-150 ppm. Some Swiss mineral waters are perfectly suitable, but others are too low in minerals, resulting in an under-extracted and bland coffee.
Regardless of the method chosen, simply filtering the water transforms an ordinary espresso into something far more expressive. If you're passionate about the subject of water, check out our article on Water as a key element of the perfect lungo explores a complementary angle. Enthusiasts who take this step never go back.
And for this difference to be truly perceptible, one must start with a grain that has something to express. A Carefully roasted organic espresso reacts dramatically to balanced water. This is the whole point of combining demanding sourcing with expert preparation, and that's exactly what you'll find in our shop.
Your online store for coffees roasted in Switzerland, inspired by the preparation methods of baristas.
With more than 50 years of experience in the coffee sector in Switzerland, Café 9|38 has accumulated valuable know-how that we are delighted to share with you to enrich your knowledge of coffee.
