Coffee is made up of 98% water so the water you are using can massively impact whether your cup tastes good or bad. The water experts at VIVREAU explain why your coffee might taste the way it does, plus how you can improve your cup of coffee by improving your water first. 

How do minerals influence the taste of coffee? 

Calcium, magnesium, sodium and hydrogen carbonate are among a few of the minerals that occur naturally in drinking water and can influence the way that coffee tastes. 

Hydrogen carbonate, in particular, is responsible for the water’s alkalinity and hardness, alongside calcium and magnesium. “When there is a lot of hydrogen carbonate or the water is too hard, it reacts with the fine caffeic acids,” explains Head of Organoleptic Department at BRITA in Taunusstein, Germany, Birgit Kohler. “The coffee then tastes unbalanced, bitter and flat.” 

Why does my coffee taste like chlorine? 

Chlorine is added to tap water, and when combined with organic residues, it can result in an unpleasant odour and taste. Even if you do not smell or taste chlorine in the water, it may still change the aroma profile of your cup once it interacts with the coffee. 

Why does my coffee taste like organic substances? 

Sometimes organic contaminants, like algae, can be identified in water, giving it a musty, earthy taste. These flavours can arise in coffee when the beans have not been dried properly or they have been exposed to moisture when stored, resulting in a cup of coffee that also tastes off. 

So, what is the ideal water to make coffee? 

“There is solid evidence that most people prefer coffee made with soft water,” explains Birgit. “It then has the perfect balance of acidity and bitterness, so that the delicate coffee aromas can develop. Coffee associations also recommend soft water with low carbonate hardness for preparing coffee.” 

For more information and to dive deeper, catch VIVREAU’s episodes at The Global Coffee Festival on 30 October. You need to register to watch — get your free ticket today!