20 Questions You Should Be Asking About Machine Espresso Before You Buy Machine Espresso

How Does Machine Espresso Work?

Machine espresso utilizes precise pressure and mind-blowing filter technology to create the perfect cup of coffee. 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, but the key difference is in the pressure.

The Group Head

The group head is the portafilter that you place in the espresso makers maker when making it. It is responsible for dispersing the water into the portafilter, and controlling the pressure of the extraction. There are many different types of group heads each with distinct advantages and drawbacks. Some focus on temperature stability, some on pre-infusion capabilities, while others are designed to control the lever. Some come with a range of features, like the E61 one, which is the standard choice for many baristas for its ability to provide multiple benefits in a single package.

As you can see from the photo above the group head has a number of notches. You can place your portafilter in these notches, then turn the head around to secure it. A gasket made of rubber is placed inside the notches, which helps create a seal when you insert your portafilter. The notches permit precise placement of the portafilter. This is crucial for a consistent extraction.

The group head not only lets the portafilter to be inserted easily however it also keeps the same temperature. It does this by circulating hot water through the brew basket and around the portafilter, ensuring that it is always at the right temperature for extraction. This is crucial, since even a small difference in temperature can mean the difference between good and great espresso.

The Pump

Unlike 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 required to extract espresso. The pressure is created by removing tap water from a reservoir, and pumping it through a heat exchanger before being shot through the ground coffee inside the group head.

Pumps tend to be less expensive than piston-driven machines, and they tend to last longer, but both types of machine can be damaged by excessive use and inadequate cleaning. They also make mechanically complex that can lead to a high price tag on even the most basic models.

Certain espresso machines can eliminate the pump completely and instead employ steam pressure to create espresso. The downside is that the boiler that produces steam also raises the temperature of the water to the point of boiling which could lead to excessive extraction. They also have to constantly rebuild their pressure in between cups. This requires energy and time.

A large majority of espresso machines employ either a vibration or rotary pump. A vibration model makes use of a rotating disk to generate pressure, whereas a circular model pushes hot liquid through the ground at a rapid speed. Both types of machine can make excellent buy espresso machine, however the rotary pumps are quieter, and more durable than vibration pumps.

The Boiler

The boiler is the one that will heat the water to the ideal temperature for extraction. The steam that is produced gets to the portafilter which contains the espresso coffee grounds. It is then pumped into the cup. During this process, steam creates pressure to push through the grounds of the coffee. This creates a layer crema that is then poured over. This is the hallmark of a great espresso.

There are three different types of espresso machines, each with different types of pumps and brew temperature. There are different ways to control the brew and the size of the cup that can be produced by the machine.

The first espresso machines were steam types. They utilized only one dual boiler espresso machine to make both steam and brew however the pressure they were able to produce was not very high end espresso machine - two bars of atmospheric pressure maximum. The coffee tasted bitter and burned. This is the reason why Milanese producers Luigi Bezzerra and Desiderio Pavoni invented the modern espresso machine.

The most common espresso machine is a semiautomatic model with an electric pump. These are the things people think of when they think of an espresso machine. Semi-automatic machines require you to grind and tamp the beans by yourself however the pump controls the flow of water and pressure. This is a fantastic solution that combines human control with mechanised consistency.

The Filter

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

A filter can also help with flavor because it allows for a longer flowering period. This allows beans to let their nuances out and provides an opportunity for a better extraction.

However it is crucial to keep in mind that even a great filter could result in a bad cup of coffee as the quality of the beans and extraction are essential.

It's in this area that the magic happens. This is the reason why espresso tastes so delicious. The grouphead (also known as the brewhead) is where you place the portafilter, the device which you put the coffee grounds in, while making espresso.

In an espresso machine that is driven by steam, hot water is heated in an airtight container to create steam, which is then pushed through the grounds under high pressure. These machines are less expensive and easier for the owner to maintain than pumps-driven models. They are however limited in their ability to create the perfect conditions for brewing as they only operate with 1-1.5 bar of pressure. The perfect shot requires 9-10 bars.

In recent years, compressed-air-pump-driven espresso coffee machines uk machines have been gaining popularity. They utilize an air compressor to force hot water into the ground and are more mobile than steam-driven electric espresso machines.