How Does Machine Espresso Work?

Machine espresso makes use of precise pressure and mind-blowing filter technology to create the delicious coffee we enjoy. How exactly does 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 major difference is in the pressure.

The Group Head

The group head is the portafilter that you place in the espresso maker when making it. It distributes water into the portafilter and controls the pressure of the extraction. There are numerous kinds of group heads each with distinct advantages and drawbacks. Some are focused on temperature stability, some on pre-infusion features, and others are designed to control the lever. Some have a combination, like the E61. This is a very popular choice for baristas due to the fact that it has multiple advantages in one package.

As you can see from the picture above the head of the group has a number of notches. You place your portafilter into these notches and turn the head around to secure it. A rubber gasket is located within the notches to create a seal while you insert your portafilter. The notches allow for an exact placement of the portafilter. This is crucial for a consistent extraction.

In addition to allowing you to easily connect your portafilter, the group head is responsible for maintaining a consistent temperature. This is accomplished by cycling hot water around the portafilter, and through the brew-basket, ensuring that the temperature is always at the right level to extract the coffee. It is important to note that even a few degree difference can make the difference between a decent and a great espresso.

The Pump

Motorized pumps in rotary travel espresso maker machines supply the nine atmospheric bar pressure that is required for espresso extraction. This is different from manually operated piston machines that employ levers. The pressure is created by drawing tap water from a reservoir and pumping it through a heat exchanger before being shot through the ground coffee inside the group head.

Pumps are typically less expensive than piston-driven machines and tend to last longer. However, both types of machine can become damaged due to excessive use and poor cleaning. They also add mechanical complexity which can result in a high price tag on even the simplest models.

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

A majority of espresso machines use the rotary or vibration pump, with a vibration model using a rotating disc that generates the pressure and the rotary model pushing hot water through theonger bloom time. This allows the beans to release their flavors, and allows for a better extraction.

It is important to remember that even the finest filter can produce a bad cup of coffee. The quality of the beans, as well as the extraction, are still very important.

This is where the magic happens, it's what makes espresso taste great. The grouphead (also known as the brewhead) is where you place the portafilter, the device that you use to put the grounds of coffee into while making Espresso Coffee Machines For Sale.

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

In recent years, compressed-air-pump-driven espresso machines have become more popular. They use an air compressor to push hot water through the ground, and are more mobile than electric espresso maker steam-driven espresso coffee machine with milk frother machines.