Water: the Most Important Part of Coffee that Isn’t Coffee

Despite its color, coffee is basically 95% water. You might guess as a result that water quality is critically important to whether an otherwise fine coffee tastes great or just okay–and you’d be right.

Recently Klaus Thomsen of the Coffee Collective felt that the city line water in his native Copenhagen was negatively affecting the delicate qualities of his roasted coffee, so he decided to do a blind taste test with waters filtered in different ways. According to Klaus:

Since we have experimented and tested a lot of water systems before we had narrowed the field down quite a bit:
1) Bottled spring water from Eden.
2) Reverse Osmosis filtered water.
3) Water+More/HOH’s new Bestmax filter.

We did the test mainly to try out the new Bestmax filter, which is a carbon and ion-exchange, four-step filter unit specifically designed for coffee.

Using the water to brew two different coffees, Klaus and co. did a blind taste test to see how each type of water affected the final cup. According to his post, the Bestmax filter performed the best, not tainting the coffee in any discernible way; largely thanks to an adjustable ion exchanger to allow calibration for different types of incoming water (i.e., from different sources). It’s not unlike achieving a flat frequency response in a loudspeaker, with the ion exchanger acting like an equalizer to compensate for any flaws in the incoming signal.

Find out how critical water can be to coffee and check out the full details of the experiment here.