How water quality affects the flavour of coffee

Sep 21, 2021 | Coffee Blends, Coffee Machines

With water making up 98% of what’s in your morning Americano, the quality of water plays an important role in determining the flavour of your coffee

Broadly speaking, in terms of coffee making in Ireland, water is divided up between ‘hard’ water and ‘soft’ water.  Hard water is richer in minerals like calcium and magnesium and occurs as ground water percolates through limestone and chalk rock.  The good news is that consuming hard water is not harmful to human health but it does affect the flavour of coffee and your equipment for making coffee, be that a kettle or a coffee machine.  Rain water is ‘soft’ water and only becomes hard as it picks up calcium and magnesium before making its way to your tap.

But how does this affect the taste of my coffee?

Areas with notably softer water will most probably enjoy a slightly lighter tasting coffee whilst those in hard water areas may find their coffee stronger and punchier. This is mainly because the flavour compounds in coffee cling to the minerals in the water.

If the water is too soft, the resulting cup can lack clarity and taste quite bland – if the water is too hard the flavour can become muddied and over-intense.   When coffee equipment is being installed or serviced, a water filter is usually fitted to treat or soften the water.  The primary motivation is to protect the coffee equipment from damage as the longer water is boiling the more calcium is removed from the water and the calcium deposits are left in the machine.  These deposits will eventually clog the pipes and valves and reduce the effectiveness of the coffee equipment..  So it’s a balancing act, we want water softened so as to preserve the health of the coffee equipment but not so soft that it leads to bland flavoured coffee.

If your coffee making is mainly happening from home then try using a simple filter jug to remove some of the calcium and judge for yourself how the flavour is affected, it’s a bit of trial and error  but  it will add a further nuance to the flavour.

If you have a coffee machine that is starting to show signs of slowing down (reduced steam pressure, reduced water flow from the brewing group or a leak occurs), there’s a good chance that calcium is building up in the machine reducing the effectiveness of valves, boilers and elements.  There are some critic acid based solutions that you can buy for home machine and by following the instructions these can reduce or remove the problem; for commercial coffee machines, by the time you notice a problem, the calcium has built up considerably so more drastic action is required.

If you would like to find out more about matching your water to Woodland Coffee, or what water filter is ideal, or if you need your commercial coffee machine descaled then please let us know,