Water makes up over 98% of a brewed coffee -- and yet it's the component most often ignored when people talk about espresso quality.
What untreated water causes
Hard water, rich in minerals (especially calcium), gradually builds up scale inside the boiler and extraction groups. Over time, this affects both the taste of the coffee and the machine's proper function -- inconsistent pressure, localized overheating, unstable temperature.
The impact on flavor
Minerals in water aren't just a mechanical problem -- they directly influence how compounds extract from the coffee. Water that's too "soft" can produce a flat extraction, while water that's too hard can mask the fine notes of a specialty coffee.
Why it matters even more in a café
A home machine, used occasionally, feels water problems more slowly. A professional machine, run continuously for hours, builds up scale much faster -- and manufacturers often make their warranty conditional on using a proper filtration system.
How a filtration system works
Filtration systems built for espresso machines reduce water hardness and remove chlorine and other impurities, while keeping a minimum level of minerals needed for balanced extraction -- over-filtering (fully demineralized water) can be just as problematic as water that's too hard.
Maintenance and cartridge replacement
Filter elements have a limited capacity and need to be replaced periodically, depending on local water hardness and coffee volume -- skipping this step gradually cancels out the benefit of filtration.
What you'll find at Cafetaria
Discover our water filtration systems, including BWT filter elements, compatible with most professional café espresso machines.