10 Tell-Tale Signs You Must See To Know Before You Buy Machine Espresso How Does Machine Espresso Work?

The machine espresso utilizes precision pressure, and a filtering technology that is amazing to create the coffee you love. What 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 main difference lies in the pressure.

The Head of the Group

The group head is the portafilter that you place in the espresso maker when making it. It disperses the water into the portafilter and regulates the pressure of the extraction. There are various kinds of group head, each with their own advantages and drawbacks. Some are designed to provide temperature stability while others are specifically designed to handle pre-infusion. Others are made to control the lever. There are some that include a mix of features, such as the E61 that is to be the most popular among baristas because of its ability to provide multiple benefits in one package.

As you can see in the photo above the group head is made up of several notches where you put your portafilter, then twist it by hand to lock it in. There is also a gasket made from rubber which is located inside the notches and helps create the seal when you insert your portafilter into the machine. The notches allow for precise placement of the portafilter. This is crucial for an even extraction.

The group head not only allows you to place your portafilter easily but also maintains a constant temperature. This is achieved by cycling hot water around the portafilter, and through the brew basin, ensuring the temperature is always right for extraction. It is important to realize that even a few degree differences can make the distinction between a good and great espresso.

The Pump

The motorized pumps that are used in rotary espresso machines supply the nine atmospheric bars of pressure required to extract espresso. This is different from manual piston machines that rely on a lever. The pressure builds up by removing tap water from a reservoir and pumping it through a heat exchanger prior being shot through the ground coffee inside the group head.

Pumps tend to be cheaper than piston-driven machines, and they tend to last longer, however both types of machines can be damaged by excessive use and inadequate cleaning. check here increase the complexity of mechanical systems and can lead to an expensive price for even the simplest models.

Some espresso machines make use of steam pressure instead of a pump to brew espresso. This can cause over-extraction because the boiler that produces steam also heats the water to boil. In addition these machines typically have to restore their pressure between cups, which requires time and energy.

Many espresso machines make use of the rotary or vibration pump. A vibration model employs a vibrating disk to generate pressure, while a rotating model pushes hot water through the ground at a high speed. Both machines produce great espresso, but rotary machines are more quiet, durable and less likely to fail.

The Boiler

The boiler is the component that heats water to an optimal temperature for extraction. The steam produced will eventually reach the portafilter, which holds the espresso grounds. It is then funneled into the cup. The steam causes enough pressure to push the grounds of coffee through. This results in a layer crema that is then poured over. This is the hallmark of a great espresso.


There are three kinds of espresso makers, which differ in the kind of pump they use and the degree of heat that the brew is. There are various ways to control the amount of brew, as well as the size of cup that can be produced by the machine.

The earliest espresso machines were steam type. They had only one boiler to make both steam and brew however, the pressure they could generate was low - only two bars of atmospheric pressure at most. The coffee tasted bitter and burned. This is why the Milanese producers Luigi Bezzerra and Desiderio Pavoni developed the modern espresso machine.

The most common espresso machine is a semiautomatic that has an electric pump. These are the images people have when they think of an espresso maker. With a semi-automatic machine you must grind the beans and tamp them by hand. However, the pump regulates the flow of water and pressure. This is a fantastic solution that combines human control with mechanised reliability.

The Filter

Typically, espresso machines employ a filter to separate out the coffee grounds as they pass through the hot water. The filter is also an essential element of the machine's temperature control, since it stops overheating.

A filter can also help with flavor since it allows for the beans to flower for a longer period of time. This allows beans to release their nuances and gives an opportunity for better extraction.

However it is crucial to keep in mind that even a high-quality filter can produce a bad cup of coffee, as the quality of the beans and extraction is vital.

This is where the magic happens, and it's what makes espresso taste great. The grouphead, sometimes referred to as the brewhead, is where the portafilter (the thingy you put the ground coffee into) is placed when making espresso.

In the steam-driven espresso machine hot water is heated in an airtight tank to create steam. Steam is then pushed through the grounds at high pressure. They are less expensive and easier to maintain than pumps-driven models. However, they are not as efficient in their ability to produce the ideal brewing conditions, since they are only operating at 1-1.5 bars of pressure. While the perfect shot requires 9-10 bar.

In recent years, compressed-air-pump-driven espresso machines have been gaining popularity. They use an air-compressor to push hot water across the ground. They are also more mobile than electric steam-driven espresso machines.