How Does Machine Espresso Work?

Machine espresso employs precise pressure and mind-blowing filter technology to make the perfect cup of coffee. But how exactly does it work?

espresso machines Home is produced by pushing hot water under pressure through finely ground coffee. The process is similar to that of making drip coffee. However the pressure is the primary difference.

The Group Head

As the name suggests, the group head is where you place your portafilter when brewing espresso. It disperses the water into the portafilter, and then controls the pressure of the extraction. There are many different kinds of group heads, each with their own advantages and drawbacks. Some are focused on temperature stability, while others on pre-infusion options, and others are designed to control the lever. There are some that include a mix of features, like the E61 one, which is the classic choice among many baristas due to its ability to offer multiple benefits in one package.

As you can see from the picture above the group head is fitted with a variety of notches. You can place your portafilter inside these notches, and then turn the head around to secure it. A rubber gasket is located inside the notches to help create a seal when you insert your portafilter. The notches permit an exact placement of the portafilter. This is vital for an efficient extraction.

The group head does not just allow the portafilter to be inserted easily, but it also maintains the temperature at a constant level. This is done by cycling hot water around the portafilter, and through the brew-basket to ensure that the temperature is constant to extract the coffee. This is important because even a few degrees can make the difference between a excellent and great espresso.

The Pump