Both coffee professionals and home baristas understand how challenging it can be to use an inconsistent grinder. With so many factors at play – from different processing methods to distribution techniques – knowing how to dial in espresso is already one of the biggest learning curves, so an under-performing grinder only adds to the frustration.

Poor particle size distribution, irregular dosing, and high grind retention can massively impede workflow, not to mention extraction. And although we already know that a good grinder can make all the difference in overall coffee quality, consistency is another key factor so that every shot of espresso is as good as the last.

To find out more about why grinder consistency is so important, I spoke to Ben Lewis, freelance barista, trainer, and coffee content creator. Read on for more of his insight.

You may also like our article on why the push for “perfect” espresso will never stop.

The grinder evolution is ongoing

Specialty coffee is an ever-changing and dynamic industry, with new technologies launched year after year. But more recently, innovation has perhaps been most evident with equipment, including espresso machines and grinders.

With more in-depth understanding of just how essential grind size and particle size distribution are for making high-quality coffee, grinders have evolved. grinders have evolved from including dosing chambers to dispensing based on a set time to utilising much more intuitive technology with a key focus on providing consistency.

Ben Lewis is an independent barista, latte artist, trainer, and coffee consultant in the UK. He is also a 2018, 2019, 2021, and 2024 UK Latte Art Championship finalist.

“As someone who is familiar with running fast-paced coffee shops and industry events, the need for consistency and accuracy is extremely significant to maintain espresso quality throughout the day,” he says.

Moreover, a consistent espresso grinder not only improves coffee quality, it can also help to optimise workflow. Key to the successful running of any café – and to baristas’ overall job satisfaction – better efficiency can reduce customer wait times, boost productivity, and even create a safer working environment. 

Another key benefit is reducing waste. Inconsistent grinders will often retain significant amounts of ground coffee, which will negatively impact extraction and impart old, stale flavours in espresso. This means baristas will have to regularly purge grinders – creating more waste and impeding workflow.

“In less busy environments, baristas have more time to carefully monitor dosing,” Ben explains. He adds, however, that as the pace of service increases, the frequency of such diligent checks can quickly drop.

“Being able to trust that a grinder produces a consistent dose each time allows a barista to think about one less variable in high-volume situations, and shift their focus on maintaining great workflow,” he tells me.

How exactly has grinder technology changed?

Over the last two decades, commercial coffee grinders have become highly sophisticated and precise. The technical aspects of espresso preparation – mainly particle size distribution (the grinder’s capability to produce ground coffee particles with relatively similar sizes) – have become even more advanced.

The shape and design of burrs have been integral to this development. Flat 85 mm burrs in particular produce much more consistent grind size by reducing the number of fines. These are very small particles that can contribute to uneven extraction when too many are present.

In turn, flavour clarity significantly improves, which allows baristas to showcase the more subtle, complex, and nuanced tasting notes in espresso.

Similarly, the combination of high capacity and low retention systems means coffee shops can often get the best results from their grinders. Eureka is a leading manufacturer of grinders which include these features, as Ben explains.

“The MAXXI grinder can consistently cope with dosing up to 10kg of coffee per day, which is a standard amount for the busiest cafés,” he says. 

Ben adds that the MAXXI grinder is also equipped with an Extremely Low Retention (ELR) system and vertical chute to help improve dose consistency.

No matter which brand or model you use, grind retention will likely never be zero. However, by reducing levels to a minimum, every dose of coffee will be fresh and precise in measurement.

“Being able to trust in dose consistency while dispensing at high speeds means baristas can spend more time and energy on focusing on other tasks while still producing great coffee,” Ben tells me.

Improving speed & workflow

“For busy cafes, speed is the name of the game,” Ben says. 

In fact, according to research by University College London, the average customer is prepared to wait in line for 5 minutes 54 seconds before they think about leaving. What’s more, after just five minutes, customer satisfaction can fall from 95% to 85%.

As Ben explains, the effort that baristas put into making coffee needs to be balanced with how long a customer is willing to wait. But mixing quality and speed isn’t always so easy. 

High-speed dispersion grinders can help facilitate this process. Ben notes: “The extra few seconds gained from every shot to focus on perfect extraction, beautifully textured milk, or pouring crisp, photogenic latte art are vital.”

During a busy rush, every second matters. Speed alone, however, is nothing without efficiency, consistency, and accuracy. Ben tells me Eureka’s Atom W 75‘s patented Instant Grind Weighing (IGW) technology, for instance, means doses are accurate to 0.1g.

“Using a grinder that dispenses consistent doses frees baristas up to think about one less variable in high-volume situations,” he says. “Making adjustments to grind size using a time-based grinder will invariably change the weight of the dose, which means baristas have to manually add or remove coffee from the portafilter.”

Naturally, this can quickly become a time-consuming task – especially during critical service times.

“Eureka’s weight variable control technology allows for much faster and less wasteful dialling in practices,” Ben adds.

How consistency can benefit coffee shops

A combination of good workflow and grinder consistency can set a coffee shop up for success. The interactions between baristas and guests has been proven to improve customer satisfaction and retention, which is especially essential for smaller businesses.

The customer experience, as well as opportunities for engagement, can be hampered, however, by the noise generated by grinders.

“The process of grinding coffee is naturally quite a loud one, and some sounds and pitches are a lot more jarring,” Ben says. “For example, higher pitches tend to be much more disruptive in a café setting when you’re trying to talk to customers.”

He adds that the Eureka Atom W 75 includes silent grinding technology, which can have noticeable impact on both barista and consumer satisfaction.

“Atom’s technology reduces grinding noise by approximately 20 decibels, which is great for maintaining engagement with customers and, of course, being able to focus more,” he explains.

Automation is a barista’s best friend

Automation is also playing an increasingly important role in coffee shops, and grinders are no exception. For instance, the Atom W 75 and MAXXI grinders – which were both showcased at World of Coffee Copenhagen from 27 to 29 June 2024 – include built-in touchscreens and different activation modes that make them more user-friendly.

Other pieces of automated equipment can also be integrated with grinders, too. Eureka recently launched its new DISKO and ATOM automatic tampers to further improve consistency.

Tamping force can vary greatly between baristas, so maintaining the same level of pressure from shot to shot is very hard to achieve.

“I used to work with a barista who also was a bodybuilder, and our perceptions of a 15kg tamp pressure were very different!” Ben notes.”The DISKO and the ATOM tampers provide a solution to this. 

“With adjustable tamping pressures, you can set the auto tamper to produce the exact same pressure for every shot you pull,” he adds.

Without a precise and dependable grinder, it’s near to impossible to extract delicious espresso in a timely manner for your customers.

The golden ratio of grinder efficiency and consistency can sometimes feel out of reach. But by investing in premium equipment that best supports baristas, coffee shops are sure to find excellent results.

Enjoyed this? Then read our article on whether crema is always necessary for excellent espresso.

Photo credits: Art Photo Espresso

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Please note: Eureka is a sponsor of Perfect Daily Grind.

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