Something in the water

With over 90% of your coffee being water, getting good quality H2O has got to be worth a bit of effort
Image – Tyler Nix / Unsplash

Fresh beans? Check. Grinder? Check. Scales? Check. Aeropress, French Press, piston or pump? Got it. You’re all set to be a domestic barista, producing tasty coffee in minutes, any time you choose. We don’t want to rain on your parade, but what are you using as your main ingredient?

The water coming out of your kitchen tap may be considered healthy to quench your thirst on a 40-degree day but in all likelihood it’s doing absolutely nothing for the flavour of your brew.

In a demonstration a few years ago by Mister Coffee himself – aka James Hoffmann – he got experienced tasters to try two coffees blind. Feedback was unanimously enthusiastic about one – a delightful blend with notes of caramel, toffee and a little burst of citrus. The other? “Dull”, “mucky”, “flat” and “lifeless” were some of the words used to describe it. Then James revealed that he’d used exactly the same beans, brewed in exactly the same way. Only for one, he’d used bottled water, for the other, tap. The difference was astonishing.

The pros have known this fact for a long time, and all good cafés will have in-line filtration systems managing their water quality. But what makes water ‘good’ for coffee?

In a report published by Adam Carr of Seven Miles Coffee Roasters, there are a couple of key factors to take into account. Hardness has a significant effect on the pure amount of flavour extracted. Between 50-80ppm (parts per million of calcium carbonate) is ideal. Exceeding this will deliver diminishing flavour returns and risk damaging your equipment.

pH balance is also critical. Carr claims that “the higher the pH, the greater the amount of flavour extracted.” To maximise flavour and consistency in extraction rates he recommends pH 7–8.5.

The easiest way to experience flavour nirvana at home is to use bottled water.

Many relatively inexpensive, own-brand bottled waters produce a really good cup of coffee with mineral and hardness levels perfectly aligned. The main downside is the negative impact on the environment, and as a longterm solution, buying bottled water is ethically flawed. However, when you’re spending all that money on wonderful beans, sourced responsibly, roasted to perfection and brewed using equipment designed to enhance them, water quality becomes a definite issue. It’s got to be worth trialling bottled water to explore the potential for improvement.

Once you’ve converted your opinion you can then explore more sustainable options. One would be to make friends with your local specialty coffee shop – if you’re not already – and ask if they would supply you with an occasional litre or two from their filtered system. It’s a nice idea and could be considered a kind of aftercare service, the way that some shops grind beans for customers who don’t own a grinder. If you’ve ever spoken to your barista about coffee, you’ll notice how

they come alive and feel genuinely passionate about it. Frankly, no one is happy about negatively affecting the taste of their beans with sub-standard water. Perhaps a small contribution would help facilitate an arrangement and prevent it from becoming a wearisome commitment for one or both of you.

Excepting those that have unfettered access to filtered water, or just have a scant disregard for discarding plastic bottles into the food chain, it’s certainly worth a discussion. You will never know unless you ask, and the flavour revelation is a tempting goal.

This is an adaptation of an original story by Chloë Callow @FaerietaleFoody