The office coffee machine is often the heart of the workplace, offering employees the opportunity to take a break and refresh both body and brain. Superior coffee beans and a choice of milks can help to improve beverage quality, but another vitally important coffee component is often overlooked: water.

Automatic coffee machines are a staple of the modern workplace, supporting productivity and wellbeing by delivering hot beverages for employees, clients and visitors at the touch of a button. Because the quality of these drinks reflects on the business, it is essential to ensure the water feeding the machine is properly optimised for the coffee-making process.

Water can make up to 98% of a coffee, depending on whether it is served black or with milk. The quality of the water not only has a major impact on taste, but also helps reduce scale build-up and prolong the life of the coffee machine. Effective water filtration is essential for an office automatic coffee machine, which may see heavy use and dispense hundreds of hot beverages each day.

For this feature, Refreshment's Bryony Andrews spoke with several industry experts to explore how the latest water filtration technologies can improve coffee quality for both consumers and professional users.

The effect on extraction

‘Extraction’ is the process where soluble compounds from roasted, ground coffee beans are dissolved into water. During extraction, hot water draws out acids, sugars, oils and other substances from the coffee. When these compounds are in balance, the result is a beverage with a well-rounded flavour and aroma.

The water used affects coffee extraction in a number of ways: through its mineral content, temperature,

pH level and purity. These factors all influence how flavours are dissolved from the grounds.

“The mineral composition of water directly affects flavour balance, aroma and mouthfeel,” confirmed Debora Screpanti, marketing manager at Blupura, a supplier of high-quality and ecofriendly water coolers and dispensers.

Screpanti told Refreshment that, according to the Specialty Coffee Association (SCA), both the hardness and the alkalinity of the water used play a crucial role in coffee extraction. Water that is too soft (less than 40mg calcium carbonate per litre) can cause under-extraction, resulting in a flat or weak cup of coffee. Water that is too hard (greater than 250mg calcium carbonate per litre) can lead to over-extraction and chalky or bitter notes.

The SCA highlights that it is actually alkalinity that determines how acidity is perceived in the cup. Alkalinity levels vary depending on the brewing method, ranging from an alkalinity of approximately 40 parts per million (ppm) for filter coffee to around 150ppm for espresso.

“Blupura’s Blutron Action filter is designed to adapt precisely to these variables,” said Screpanti. “Thanks to its adjustable Bypass, users can fine-tune the water composition based on the incoming water and the desired coffee profile, reducing or increasing hardness as needed. This flexibility ensures optimal flavour extraction and consistent quality in every cup.”

According to Emma Redford of H2O Direct, an expert in water filtration products for the coffee, vending and point-of-use (POU) water cooler industries, the ideal pH of water for coffee extraction would be between 6.5 and 7.5.

Redford said: “If the water is too soft, this can lead to flat, sour-tasting coffee, whereas water that is too hard will result in a bitter, chalky taste. The goal is for the water to have balanced mineral content and alkalinity to brew a consistent high-quality coffee.”

Removing contaminants

According to Anastasia Chovan, certified water sommelier at premium water dispenser manufacturer Vivreau, organic compounds and residual disinfectants in water can negatively impact the coffee experience.

“Properly treated water contains the right balance of minerals, like calcium and magnesium, which bind with coffee compounds to extract a balanced and flavourful cup,” she said. “In contrast, organic matter and residual disinfectants, such as chlorine, can introduce off-flavours and odours. Effective water treatment removes these contaminants, ensuring a clean taste that preserves the coffee’s natural profile.”

Patrick Aigeldinger of Crystal IS, a provider of UVC LED water disinfectants, also addressed the importance of filtration from a contaminant perspective. He told Refreshment: “Water can contain trace amounts of bacteria, spores or biofilm from pipes and holding tanks. Even if not dangerous, these can create subtle off-flavours or odours and interact with coffee compounds during extraction. Using UVC treatment – especially at germicidal wavelengths like 265nm – inactivates microbes and leads to cleaner-tasting water, letting the flavour profile of the coffee shine through.”

We have learned that water is far more than just a solvent – it is a key component of any brewed coffee. Its composition greatly influences the flavour, aroma and mouthfeel of the beverage, making proper filtration a true ‘make or break’ step in the coffee-making process.

Ultimately, when water is filtered to optimise it for coffee, it leads to a better-tasting beverage. Removing substances that add undesirable flavours, such as chlorine and organic compounds, and balancing water hardness and alkalinity to an optimal level supports ideal extraction, and this in turn allows the complex flavours and aromas of the coffee to be shown to their best advantage.

Filtering for performance

For employers, investing in beverage equipment – in particular coffee machines – is an investment in worker satisfaction and productivity. However, it is also a significant financial outlay, and once installed, automatic coffee machines need ongoing maintenance to ensure they are operating at their full potential.

As Samantha Scoles, sales director at Brita Professional, told Refreshment, maintenance goes beyond simply keeping the exterior clean and in good working order: equal attention must also be paid to the interior of the machine. Scoles identified the build-up of limescale as one of the leading causes of hot beverage equipment failure.

“Even a thin layer of just 1mm can drive up energy use by 7% and shorten machine lifespan,” she said. “Water filters reduce water hardness down to a level where scale isn’t able to form. The latest smart filtration technology takes that protection a step further by continuously monitoring water quality, tracking hardness and alerting the operator in real time when filters need replacing."

"This ensures machines are always safeguarded against limescale and, ultimately, delivers longerlasting value from your investment.”

Vivreau’s Chovan advises that water quality plays a critical role in the longevity and performance of coffee equipment, and identifies two key ways that the right water filter can help: firstly, aiding in mineral control, and secondly, facilitating disinfectant removal.

“Minerals like calcium and magnesium, while essential for flavour, can accumulate inside coffee machines, leading to scale build-up,” said Chovan. “Over time, this can reduce efficiency, increase

energy consumption and cause costly damage. A properly selected filter balances mineral content

to protect equipment while preserving taste.”

She continued: “Disinfectants such as chloramine, commonly used in municipal water treatment, can be corrosive to internal components and lead to maintenance issues. Advanced filtration systems are designed to remove these compounds, ensuring smoother operation and reducing service needs.”

H20’s Redford offers similar advice. She said: “Using an Ion Exchange Resin filter from the IEN range from H2O Direct will help prevent scale build-up and is essential to ensure consistent operation, which reduces maintenance costs and prevents damage to the machinery and its components.”

Blupura’s Screpanti agrees that scale and corrosion are the two main threats to coffee equipment. “When minerals precipitate inside boilers, pipes and valves, they reduce thermal efficiency and can cause severe mechanical damage over time,” she warned. “Our Blutron Action filter prevents this by reducing hardness and filtering out sediments and organic contaminants. It ensures that water entering the machine is clean, stable and safe for its components. This not only preserves the brewing performance but also significantly extends the lifespan of the machine, keeping maintenance costs under control and ensuring consistent performance.”

The right solution for your business

Water composition varies widely between regions, from very soft to extremely hard, so filtration needs can differ to protect equipment. The expected usage of the coffee machine must also be considered, meaning that choosing the right filtration system for an office is rarely a one-size-fits-all decision.

“Water testing provides a clear picture of your local water’s mineral content, organic compounds and disinfectants” advised Vivreau’s Chovan. “With this information, your water consultant can recommend the right filtration and treatment solutions tailored to your equipment and coffee goals.”

She continued: “No two water sources are the same, so a water test ensures your filtration system is custom-designed to balance flavour and protect your equipment. Water composition can also change with the seasons due to environmental factors or shifts in municipal treatment. Regular testing – especially in winter and summer – helps adjust filtration to maintain consistency and meet increased demand. By starting with a water test and maintaining seasonal awareness, you can ensure your coffee tastes great year-round and your equipment stays protected.”

H2O’s Redford shares that, “the hardness of local water can be easily found using the H2O Direct water hardness checker, which is utilised by way of a postcode…Once the hardness is established, a suitable filter should be used and appropriate settings applied.” H2O Direct offers a Variable Head IEN filter, which allows the user to alter the blending of the water through the filter, where the existing hardness or pH level needs to be changed.

From Blupura, the Blutron Action filter has a bypass system that allows technicians to easily adjust hardness and alkalinity according to local conditions. “By referring to our bypass configuration table, operators can set the correct mixing ratio between filtered and untreated water based on the hardness of the incoming supply and the desired output,” explained Screpanti. “This way, a single filter model can be used effectively anywhere, providing the right mineral balance for both flavour and machine protection. This versatility makes the Blutron Action a universal, adaptable solution for professional coffee applications worldwide.”

Crystal IS’ Aigeldinger noted that many high volume operators integrate UV into their water treatment line, in addition to a sediment and carbon filter. “This ensures consistent water quality across locations,” said Aigeldinger. “It’s especially useful in places with variable municipal water or tank storage.”

Supporting customers with their maintenance schedule

Neglecting maintenance or using coffee equipment that is in need of repair inevitably affects machine productivity and reflects poorly on the business. For filtration, this means replacing cartridges at the recommended intervals and keeping a regular service schedule. Partnering with a filtration provider that offers maintenance support and advice can take much of the stress out of servicing for office facilities managers.

In addition to extending the life of the coffee machine, regular servicing helps to preserve flavour and aroma of the coffee produced. Blupura’s Screpanti states that, “proper maintenance guarantees consistent extraction, stable performance and the high beverage quality expected from every cup”.

H20 Direct’s Redford similarly noted that supporting customers with a proactive maintenance schedule not only protects their investment, but also ensures that every cup meets quality expectations, even under high-volume conditions.

“Without proper use of filtration, limescale can form on elements within the equipment which can cause breakdowns, user dissatisfaction, reduce temperature control and flow consistency,” Redford warned. “Changing the filters after six to 12 months and installing the correct size of filter will reduce any maintenance issues that may arise”.

Vivreau’s Chovan agrees that water filters should also be changed at least annually to prevent limescale build-up and the resulting reduced efficiency, costly repairs and poor coffee taste. Chovan also recommends staying ahead of seasonal water changes and usage spikes to help avoid unexpected issues and keep coffee tasting great. “Regular maintenance and water filter management are simple steps that protect your investment and ensure every cup meets your quality standards.

Brita’s Scoles recommends “smart, data-driven water filtration technology” as the most effective way to manage coffee equipment maintenance. She explained: “By using filtration systems that actively monitor water quality and alert operators when maintenance is needed, caterers can take the guesswork out of water management and utilise a more preventative approach, avoiding surprise breakdowns and minimising waste”.

Systems like Brita’s Purity C iQ and iQ Meter, for example, monitor water quality in real time as well as tracking filter performance across an entire operation. This ensures filters are only replaced when they genuinely need to be, avoiding unnecessary costs and helping equipment last longer.

“This precision scheduling reduces waste, supports sustainability goals and keeps maintenance efficient, particularly when paired with cartridge recycling programmes and robust waste management initiatives,” Scoles advised.

Ultimately, filtration is a vital step in office coffee service provision. It optimises machine performance and prolongs machine life, as well as enhancing the coffee’s flavour and aroma by removing taste-altering contaminants. Essential in a high volume location, proper filtration means automatic coffee machines operate more efficiently, require less maintenance and consistently produce top-tier coffee.