An In-Depth Look Into The Future What's In The Pipeline? Machine Espresso Industry Look Like In 10 Years? How Does Machine Espresso Work?

Machine espresso makes use of precise pressure and incredible filter technology to produce the delicious coffee we enjoy. How exactly does it work?

Espresso is made by pushing hot water at high pressure through finely ground coffee. The process is similar to making drip coffee. However, the pressure is the main difference.

The Group Head

The group head is the portafilter you put in when making espresso. It disperses water in the portafilter and controls the pressure of the extraction. There are many different types of group heads, each with its own advantages and disadvantages. Some are focused on temperature stability, whereas others on pre-infusion capabilities, and still others are designed to control the lever. There are also some that come with a range of features, like the E61 one, which is to be the most popular among baristas due to its ability to offer multiple benefits in a single package.

As commercial espresso machine can see in the above photo the group head comes with several notches where you place your portafilter and twist it manually to lock it in. A gasket made of rubber is positioned in the notches to create a seal as you insert your portafilter. The notches on the head allow for a precise location of the portafilter which is vital to ensure a consistent extraction.

In addition to allowing you effortlessly insert your portafilter the group head is responsible to ensure that the temperature remains even. This is achieved by cycling hot water around the portafilter, and through the brew-basket, making sure that the temperature is always at the right level to extract the coffee. It is important to note that even a slight differences can make the distinction between a good and a great espresso.

The Pump

Motorized pumps in espresso machines rotary provide nine atmospheric bar pressure required for espresso extraction. This differs from manual piston machines which use levers. This pressure is generated by pumping water through a heat exchanger and then through the ground coffee.

Pumps are typically less expensive than piston-driven machines and tend to last longer, however both types of machines may get damaged through overuse and lack of cleaning. Pumps are also more complex mechanically, which could increase the price of even the simple models.

Certain espresso machines do away with the pump completely and employ steam pressure to create espresso. This can lead to over-extraction as the boiler that produces steam also causes the water to boil. In addition the machines often have to restore their pressure between cups, which requires time and energy.

Many espresso machines employ either a rotary or vibration pump, with a vibrating model that uses a vibrating disc that generates the pressure, and rotating models that push hot water through the grounds at high speed. Both machines produce great espresso, but rotary machines are quieter, more durable and less likely to break.

The Boiler

The boiler is the component which heats the water to the ideal temperature to extract. The steam that is produced reaches the portafilter, which contains the ground espresso coffee, and is then pumped into the cup. During this process, steam creates pressure to push through the coffee grounds. This creates a foam on the top of the espresso. This is one of the hallmarks of a great espresso.

There are three kinds of espresso machines, each with different pumps and brew temperature. There are a variety of ways in which the brew could be controlled and the size of the cup that the maker can create.

The first espresso machines were steam-based. The earliest espresso machines were steam types. The coffee tasted bitter and burnt. This is why the Milanese makers Luigi Bezzerra and Desiderio Pavoni developed the modern espresso machine.

The most commonly used espresso machine is a semiautomatic with an electric pump. These are what people imagine when they think of an espresso maker. With a semi-automatic espresso machine, you need to grind the beans and tamp them by hand. The pump regulates the flow of water and pressure. This is a great compromise between the human touch and the mechanised consistency.

The Filter

Espresso machines typically use filters that separate the grounds of the coffee from the hot water. The filter is also a vital part of the temperature control system, because it stops the machine from overheating.

It also helps with flavor, as it can allow for a longer bloom phase. This allows the beans to release their nuances and gives an opportunity for better extraction.


However it is crucial to remember that even a good filter can make a terrible cup of coffee as the quality of the beans and extraction is still vital.

This is where the magic happens, and it's what makes an espresso really taste good. The grouphead, sometimes referred to as the brewhead, is where the portafilter (the thing you put the coffee grounds into) sits when you're making espresso.

Steam-driven espresso machines use hot water heated in an airtight container to produce steam. The steam then pushes hot water into the grounds of the coffee under pressure. These kinds of machines are usually cheaper and easier to maintain than pumps-driven models. However, they are not as efficient in their ability to produce the ideal conditions for brewing as they only operate at 1-1.5 bars of pressure. However, the perfect shot requires 9-10 bars.

In recent years, espresso machines driven by a compressed air compressor have become increasingly popular. They use an air-compressor to force hot water into the ground and are much more mobile than electric steam-driven espresso machines.