In any coffee shop, the grinder is arguably the most important piece of equipment, however, we can easily overlook its integral role. Even when paired with the most advanced espresso machine, a poor-performing grinder will massively impede extraction and flavour.

Over the past few years, both espresso machine and grinder technology have come a long way, but for the latter, evolution has been particularly remarkable. At trade shows and coffee events, manufacturers often shine the spotlight on their latest grinders, which are now smarter and more intuitive than ever.

To explore how high-tech grinders will drive innovation in specialty coffee to reach new heights, Marco Beltrame, After Sales Manager at Dalla Corte, provides his insight.

You may also like our article on how espresso machine technology has changed in the 21st century.

A brief history of coffee grinding

It’s fascinating to see how coffee grinding has developed over time, with modern manufacturers having a razor-sharp focus on precision and uniformity. 

In a very traditional sense, people can grind coffee with a mortar and pestle or similar apparatus. This practice has existed in places like Ethiopia for centuries, where ancient coffee-drinking culture is still prevalent today.

During the 15th century, the first hand-held spice grinders were developed, and there is evidence to suggest they were also used to grind coffee. It wasn’t until the 1600s that the first known device specifically designed to grind coffee was patented by Nicholas Book.

As global coffee consumption increased, demand for home grinders grew. By the end of the 19th century, most households in Europe and the US owned a hand-cranked coffee grinder.

The advent of espresso in the early 20th century led to the development of the first commercial electric grinders – revolutionising how baristas prepared coffee forever. 

The push for better grinder efficiency

Marco Beltrame is the After Sales Manager at Dalla Corte – a leading manufacturer of espresso machines, grinders, and coffee equipment. 

“Grinding is, of course, a crucial part of extracting the perfect cup,” he tells me. “Just like espresso machines, grinders have evolved, which improves the quality of extraction and flavour.

“Grinding speed has improved dramatically over the years, so models with dispensing chambers have almost disappeared in the high-end market,” he adds.

Dispensing grinders are certainly efficient, but don’t typically lead to the best results in the cup. As coffee is pre-ground into the dispensing chamber, it can quickly become stale and lose some of its volatile flavour and aroma compounds. 

To avoid this problem, more and more manufacturers started to design volumetric and timed grinders:

• As its name suggests, a timed grinder grinds coffee for a predetermined amount of time – one which is set by the barista
  • For example, if a recipe calls for 18g of coffee and it takes 5.8 seconds to grind this dose, this is the setting needed
• A gravimetric grinder measures the coffee’s weight as it dispenses into the portafilter
  • The motor turns off when the pre-programmed weight (also set by the barista) is reached

Many agree that gravimetric grinders perform better than timed grinders, largely because they require less frequent calibration and tend to result in more accurate doses – improving workflow and efficiency.

Flat vs conical burrs

Flat burrs have also had a huge impact on grinding efficiency. These are two ring-shaped burrs that sit on top of each other, so the distance between them determines grind size. This means grinding happens horizontally, which results in unimodal particle size distribution, and thereby produces more evenly sized ground coffee particles. Ultimately, this makes for a more even extraction, and can also result in more experimentation with grind size and its effect on flavour.

Conical burrs, meanwhile, include one cone-shaped burr that sits inside the other, which is ring-shaped. This means they grind coffee vertically, so gravity plays a key role. These burrs result in bimodal particle size distribution, which essentially means that they produce more of both smaller and larger-sized particles.

There is much debate about which types of burrs perform better. Generally speaking, flat burrs are more consistent, but are often more expensive, noisy, and can heat up quickly under certain conditions. Conversely, most conical burrs are quieter, cooler, and more affordable, but less consistent.

New standards for excellence

To make great-tasting coffee (especially espresso), the importance of an excellent grinder cannot be overstated. Even if a barista dials in their coffee perfectly, the wrong grind size or uneven particle size distribution can quickly undo their hard work.

Over the last decade or so, manufacturers have integrated new and more advanced technologies into their grinders to improve quality and efficiency even further. 

“Today, common features include integrated scales and wireless connections to espresso machines to give users even more control,” Marco explains.

In fact, many technologies have become standard in high-performing grinders. Ultra-fine micrometric grind adjustments (which measure to one-millionth of a metre) grant users maximum control over grind size to unlock the full potential of espresso. 

Combined with reduced grind retention that minimises the risk of extracting old, stale coffee, dosing is also more precise than ever before – with measurements dispensed accurate to ±0.1g. Touchscreens are now also an expectation for grinders, making them more user-friendly to effortlessly save and switch between preset recipes.

Regulating temperature

A particularly interesting innovation has been temperature-controlled burrs, as Marco tells me.

“Coffee is subject to changes in temperature and humidity, which means you have to make constant grinding adjustments throughout the day,” he says. “This affects both extraction time and cup quality, and the latter can quickly deteriorate without maintaining the optimal grind size.”

Moreover, as burrs rotate incredibly quickly, they generate a lot of heat when used continuously, which inevitably increases the temperature of ground coffee. 

“A stable temperature in the grinding chamber not only makes for a more consistent dose, but it also means baristas don’t need to adjust the grind size as much throughout the day,” Marco says. “You therefore waste less coffee when dialling in and purging the grinder.”

He adds that certain features – such as Dalla Corte’s built-in temperature probes and ventilation systems – can help to regulate temperature in the grinding chamber to minimise any negative impact.

How new grinder technology will reshape extraction

Although grinders have become more efficient and precise over the past decade, manufacturers are continuing to push for further innovation to improve extraction and flavour.

Compared to timed grinders, gravimetric models perform better, but there is still room for improvement, as Marco explains.

“Gravimetric coffee grinders have become increasingly common in coffee shops as technology has improved,” he says. “Despite this, this system still isn’t efficient enough to fully optimise barista workflow – an aspect that I consider fundamental to defining a technology as truly ‘smart’.”

As gravimetric grinders are unable to automatically adjust grind size based on different bean densities and temperatures, baristas need to spend time recalibrating grinders throughout their shifts.

Marco tells me that Dalla Corte has developed a solution to eliminate this problem: the Grinder Control System (GCS). This technology allows the barista to digitally connect their grinder with an espresso machine. When certain variables change or any issues arise related to channelling, the espresso machine automatically signals to the grinder to adjust the grind size so baristas can achieve more even extraction.

“Once you save a recipe on the espresso machine, the Grinder Control System monitors time and yield to ensure consistency,” Marco explains. “Every five shots, if the system detects a high error rate against the set parameters, it signals to the grinder to adjust grind size and time.

“The goal of Dalla Corte’s GCS is to maintain a highly consistent and accurate timed dose to improve the overall efficiency of the grinding process,” he adds.

But the benefits extend beyond making great espresso

Improving grinder technology certainly leads to better quality extraction, but it also helps to enhance barista workflow and coffee shop efficiency – which has become more important than ever.

High staff turnover rates have always been an issue in the hospitality industry, and the pandemic only made the situation worse. In July 2023, trade association UK Hospitality reported that national job vacancies were 48% higher than before Covid-19 – with fewer people incentivised to work in the hospitality sector. 

For coffee shop operators, this means investing in barista training becomes more challenging, yet still crucial to serve excellent coffee.

Marco explains that Dalla Corte designed the Grinder Control System in 2008 to address this specific problem.

“We developed this grinder technology to streamline café operations, including for less experienced baristas who may have limited knowledge of how to dial in different coffees,” he says.”

Highly-skilled staff can also benefit from better grinder efficiency. Instead of spending valuable time adjusting grind size, baristas are able to focus on other tasks, such as customer interaction or developing new recipes.

“The simplicity and effectiveness of the Grinder Control System has led some coffee chains to replace automatic machines with semi-automatic espresso machines,” Marco adds.

In terms of innovation, grinder technology is leading the charge in specialty coffee. By combining advanced features, precision engineering, and ergonomic design, manufacturers can help baristas achieve the best results time after time.

Looking ahead, grinders are only set to become even more intuitive and cutting-edge – which will only help push quality standards even higher.

Enjoyed this? Then read our article on how coffee competitions have changed in recent years.

Photo credits: Dalla Corte

Perfect Daily Grind

Please note: Dalla Corte is a sponsor of Perfect Daily Grind.

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