10 Meetups About Machine Espresso You Should Attend

How Does Machine Espresso Work?

The machine home espresso machine makes use of precision pressure, and a filter technology that is awe-inspiring to create the coffee you enjoy. What exactly is it that makes it work?

Espresso is made by pushing hot water under 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 insert when brewing espresso. It is responsible for dispersing water into the portafilter, and controlling the pressure of the resulting extraction. There are many different types of group heads each with its own advantages and disadvantages. Some are designed for the stability of temperature while some are specifically designed to handle pre-infusion. Others are made to control the lever. Some are a combination, like the E61. This is a preferred choice for baristas because it offers multiple benefits in one package.

As you can see from the photo above the head of the group is equipped with several notches. It is possible to place your portafilter in these notches, then twist the head to secure it. There is also a gasket made from rubber in the notches and helps create the seal when you insert your portafilter into the machine. The notches on the head allow for a precise positioning of the portafilter which is crucial for an efficient extraction.

The group head is not just able to allow the portafilter to be inserted easily however, it also keeps the same temperature. It does this by cycling 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 be the difference between a excellent and great espresso.

The Pump

The motorized pumps used in espresso machines rotary provide nine atmospheric bar pressure that is required to extract espresso. This is different from manual piston machines which use a lever. This pressure is generated by pumping water through a heat-exchanger and then through the ground coffee.

Pumps are typically less expensive and last for longer than piston-driven machines. However, both types of machines can deteriorate because of 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 employ steam pressure instead of a pump in order to brew espresso. The disadvantage of this is that the boiler that produces steam also increases the temperature of water to boiling and can result in excessive extraction. The machines must also constantly rebuild their pressure in between cups. This requires energy and time.

A majority of espresso machine small machines utilize either a vibration or rotary 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 types of machines are capable of producing excellent espresso, but the rotary models are quieter and more durable than vibration pumps.

The Boiler

The boiler is the one that makes the water warm to the ideal temperature for extraction. The steam created gets to the portafilter which is a container for espresso grounds. It is then funneled into the cup. In this process, the steam creates pressure and pushes through the coffee grounds. This results in a layer of crema on top. This is a sign of a great espresso.

There are three distinct types of espresso machines, each having distinct pumps and brew temperature. There are various ways to control the brew and the size of cup that can be made by the machine.

The earliest espresso machines were steam-based. They had one dual boiler espresso machine bean to cup espresso machines create both steam and brew however, the pressure they could create was minimal - two bars of atmospheric pressure maximum. The coffee tasted bitter and burnt. This is why the Milanese producers Luigi Bezzerra and Desiderio Pavoni created the modern espresso machine.

The most common espresso machine is a semiautomatic that has an electric pump. When people think of espresso machines, they imagine these machines. Semi-automatic machines require you to grind and tamp the beans by yourself however the pump controls the water flow and pressure. This is a fantastic combination of human control and mechanised reliability.

The Filter

Typically, espresso machines utilize filters that separate the coffee grounds as they pass through the hot water. The filter is also an essential part of the temperature control system, as it prevents the machine from overheating.

A filter can also help with flavor since it allows for an extended flowering time. This helps the beans release their flavors and provides the chance for better extraction.

It is important to keep in mind that even the finest filter could result in a poor cup of coffee. The quality of the beans and the extraction, are still crucial.

This is where the magic happens, it's the thing that makes espresso taste good. The grouphead, sometimes referred to as the brewhead, is where the portafilter (the device you put the ground coffee into) sits when you're making espresso.

Steam-driven espresso machines use hot water that is heated in an airtight container to make steam. The steam then moves hot water through the coffee grounds under high pressure. They are less expensive and easier for the owner to maintain than pumps-driven models. However, they are not as efficient in their capacity to create the perfect brewing conditions because they operate at 1-1.5 bars of pressure. The perfect shot requires 9-10 bars.

In recent years, best espresso machine under 500 machines driven by compressed air-pump have become increasingly popular. They use an air compressor to push the hot water through the grounds and are more portable than steam-driven electric machines.