Coffee poring into a cup from the coffee machine.

How the power of water can unlock great tasting coffee and improve sustainability

Reducing limescale is key for a consistently quality cup and machines that stand the test of time

Sustainability is firmly on the menu for coffee shops today and with good reason. While the conversation around sustainable and ethically sourced coffee has been underway for some time, environmental sustainability, traceability, and recyclable packaging and utensils all remain important concerns for UK coffee drinkers.

And when it comes to that all-important flavour of the perfect espresso, it’s understandable that most people look to the beans first. But should water be an equally important part of the equation? After all, 98% of a cup of coffee is water, so to get the ideal flavour and extractions from those delicious beans, considering the science behind water is crucial.  

UK coffee shops already have a good reputation for sustainability and great flavours, but did you know how smart water filtration could help boost these even further? Samantha Scoles, qualified water sommelier and Sales Director at BRITA Professional, takes a deep dive into the issue of unfiltered water, its influence on taste and its little-recognised environmental impacts.

Water is being poured into the coffee cup from a coffee machine.

Recipe for success

Chlorine in the UK’s water supply has a very potent aroma and taste that’s detectable even at very low levels, and even naturally occurring organic compounds in water can affect its taste. The best coffee deserves water purified of these substances. But what should you be looking for?

The water’s hardness should be between 50 and 175 parts per million (ppm) of total dissolved solids (TDS) per million. Of course, we all have our own personal tastes, but there is a general consensus that when the water is too hard, you'll have a dull, lifeless coffee. If the water is too soft, you’ll have an over-extraction – it's going to be too bitter. It's all about balance.

The alkalinity is the most important factor and is sometimes referred to as “buffer capacity” or “buffer capacity hydrogen carbonate”. Too high, and you won’t get those beautiful, delicious flavours; too low, and you’ll get too much acidity. Its TDS value should be between 40 and 75 parts per million, and the pH value between 6 and 8.

One of the ways we determine Total water hardness and alkalinity is by carrying out drop tests using a BRITA drop test kits. For Total hardness, you’re looking for the water in the vial to turn green with between 3 and 10 drops. For alkalinity, you want the water to turn yellow with between 2 and 4 drops.

When you get within a balanced range, then you know you're going to get a really great tasting cup of coffee. But aside from impacting taste, what are the issues when using unfiltered water to brew coffee?

Barista pouring milk into a coffee cup in a coffee shop.

A question of scale

As a coffee professional, you’ll know that when hard, unfiltered water is heated, it causes a chemical reaction that leads to limescale build up in your equipment. Left untreated, you’ll soon find your brews become undrinkable. And not only does limescale spoil the beverages you serve – and your hard-won reputation for serving delicious coffee – but it can harm our environment too.

Barista using a coffee machine in a coffee shop.

Reduce energy consumption

The fact is, scale equals increased energy consumption. Even just a millimetre of scale can reduce the energy efficiency of your equipment, costing you more to heat your water. With bills rising, that’s an unnecessary expense that cafés can avoid.

And it’s an increased carbon footprint that our planet can’t afford either. As the UK strives to reach net zero emissions by 2050, coffee shops are keen to play their part – and reducing limescale through water filtration is an easy win.

Barista working in coffee shop

Extend appliance lifespan

Plus, when limescale accumulates inside your equipment, it can cause them to breakdown and is likely to reduce their lifespan. That’s unnecessarily expensive, and from a sustainability standpoint, it results in appliances being sent to landfill early. What’s more, manufacturing new appliances uses more raw materials and energy.

By filtering your water, you can protect the fantastic equipment that you’ve invested in – and protect our planet too. Look out for a filter that can reduce the hardness of your water down to a level where scale can’t form. And, to make sure you aren’t taking one step forward and two back, look for filters that come with recyclable cartridges, or even better, a supplier that can recycle them for you.

Our latest model, the PURITY C iQ, takes the guesswork out of going green. This industry-first smart filtration system, designed with and for coffee professionals, monitors your café’s water intake, checks its hardness, and tells you in real-time when you need to change filters. You can stop limescale build-up in its tracks, cut your energy usage, prolong the lifespan of your valuable equipment, and serve the perfect cup consistently every time.

Take the next step on your business sustainability journey by finding out more about PURITY C iQ.

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