12 Companies Setting The Standard In Machine Espresso

How Does Machine Espresso Work?

The machine espresso uses precision pressure, and filtering system that is awe-inspiring to create the coffee you love. What exactly is it that makes it work?

Espresso is made by forcing hot water under high pressure through finely-ground coffee. The process is similar to making drip coffee but the key difference is in the pressure.

The Group Head

The name implies the group head is the place you place your portafilter when brewing espresso. It disperses water in the portafilter and controls the pressure of the extraction. There are numerous kinds of group heads each with distinct advantages and drawbacks. Some are specifically designed for temperature stability while others are specifically designed to handle pre-infusion. Others are made to control the lever. Some come with a combination of both, like the E61. This is a popular choice among baristas as it provides a variety of advantages in one package.

As you can see in the photo above the group head is made up of numerous notches that you can place your portafilter and twist it with your hands to secure it. A gasket made of rubber is placed inside the notches, which helps create a seal while you insert your portafilter. The notches on the head allow for an exact positioning of the portafilter which is vital to ensure an efficient extraction.

In addition to allowing you to easily insert your portafilter, the group head is also responsible to maintain an even temperature. It does this by cycling hot water through the brew basket, and around the portafilter, ensuring that it's always at the right temperature to extract. This is important because just a few degrees could make the difference between good and great espresso.

The Pump

In contrast to manual piston machines which rely on a lever to pressurize water, the rotary espresso machines use motorized pumps to supply the nine atmospheric bars of pressure needed to extract espresso. The pressure builds by removing tap water from a reservoir, and pumping it through a heat exchanger prior it is shot through the ground coffee in the group head.

Pumps tend to be cheaper and last longer than piston-driven machines. However, both kinds of machines may degrade because of excessive use and inadequate cleaning. Pumps are also more complex mechanically, which could increase prices of even simplest models.

Certain professional espresso maker machines eliminate the pump completely and instead utilize steam pressure to make espresso. This can lead to over-extraction as the boiler that makes steam also heats the water until it comes to a boil. Additionally, these machines frequently have to rebuild their pressure between cups, which takes time and energy.

Many espresso machines make use of the rotary or vibration pump. A vibration model uses a vibrating disk to generate pressure, whereas the circular model pushes hot liquid through the ground at high speed. Both machines can make great buy espresso machines, but rotary machines are more stable, quieter and less likely to break.

The Boiler

The boiler makes the water warm bean to cup espresso machines the ideal temperature for extraction. The steam created gets to the portafilter which contains the espresso coffee grounds. It is then funneled into the cup. The steam creates pressure and pushes through the grounds of the coffee. This creates a crema on the top of the espresso. This is one of the main characteristics of a good espresso.

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

The first best home espresso machine machines were steam-type. They used one boiler to create steam and brew, however the pressure they were able to create was minimal - two bars of atmospheric pressure at most. This resulted in the coffee tasting bitter and burnt. The modern espresso machine was invented by the Milanese producers Luigi Bezzerra & Desiderio Pavoni.

The most popular espresso machine is a semiautomatic with an electric pump. This is what people envision when they think of an espresso machine. If you have a semi-automatic machine you grind the beans and tamp them by hand. However, the pump provides regulated water flow and pressure. This is an excellent compromise between human touch and the mechanised accuracy.

The Filter

Espresso machines usually have a filter that separates the coffee grounds from the hot water. The filter is also an essential component of the machine's temperature control, as it helps prevent overheating.

It also improves flavor, as a filter allows for a more prolonged bloom time. This helps the beans let their nuances out and provides the chance for better extraction.

However, it is important to remember that even a top filter can produce a bad cup of coffee, as the quality of the beans and extraction is still vital.

It's here that the magic takes place. This is what makes espresso taste so good. The grouphead, also called the brew head, is where the portafilter (the container you place the ground coffee in) is placed when making espresso.

Steam-driven espresso machines make use of hot water heated in an airtight container to produce steam. The steam then pushes hot water into the grounds of coffee under high pressure. These machines are less expensive and easier for the user to maintain than pumps-driven models. They are however limited in their ability to create the ideal conditions for brewing since they only operate with 1-1.5 bar of pressure. The perfect shot requires 9-10 bars.

In recent years, compressed air-driven espresso machines have been gaining popularity. They use an air compressor to push hot water through grounds and are much more portable than electric steam-driven machines.