10 Meetups On Machine Espresso You Should Attend

How Does Machine Espresso Work?

Machine espresso makes use of precise pressure and incredible filter technology to produce the delicious coffee we enjoy. How does it work exactly?

Espresso is made by pushing hot water at high pressure through finely-ground coffee. The process is similar to that of making drip coffee. However, the pressure is the main difference.

The Group Head

The group head is the portafilter you place in the espresso maker when making it. It disperses water in the portafilter, and then regulates the pressure of the extraction. There are a variety of types of group head, each with their distinct advantages and drawbacks. Some are specifically designed for stability of temperature while others are specifically designed to handle pre-infusion. Others are built to control the lever. Some come with a range of features, like the E61, which is considered the most popular choice among baristas due to its ability to offer multiple benefits in one package.

As you can see in the image above, the group head has many notches in which you can put your portafilter, then twist it by hand to secure it. There is also a gasket made from rubber in the notches to help create the seal when you insert your portafilter into the machine. The notches on the head allow for a precise location of the portafilter which is necessary for an even extraction.

The group head does not just allow you to put in your portafilter easily but also maintains the temperature at a constant level. It does this by cycling hot water through the brew pan and around the portafilter, ensuring that it is always at the right temperature for extraction. It is important to remember that even a slight variation can mean the difference between a decent and a excellent espresso.

The Pump

The motorized pumps that are used in espresso machines rotary provide nine atmospheric bar pressure that is required for espresso extraction. This is different from manual piston machines which use levers. The pressure builds by drawing tap water from a reservoir, and pumping it through a heat exchanger prior it is shot through the ground coffee inside the group head.

Pumps are generally less expensive and last for longer than piston-driven machines. However, both kinds of machines are susceptible to degrading due to overuse and inadequate cleaning. They also make mechanically complex, which can result in the cost of even the most basic models.

Some espresso machines employ steam pressure instead of a pump for brewing espresso. The downside is that the boiler that produces steam also raises the temperature of water until it reaches boiling which can cause excessive extraction. The machines also need to continually rebuild their pressure between cups. This requires energy and time.

espresso machines uk  make use of a rotary or vibration pump. A vibration model makes use of a rotating disk to generate pressure, while a Rotary model pushes hot coffee through the ground at a high speed. Both types of machine are capable of producing excellent espresso, however rotary machines are quieter and more durable than vibration pumps.

The Boiler

The boiler is the one that makes the water warm to the perfect temperature for extraction. The resulting steam reaches the portafilter, which contains the ground espresso and is then pumped into the cup. In this process, the steam creates pressure and pushes through the coffee grounds. This results in a crema on top of the espresso. This is a hallmark of a great espresso.

There are three kinds of espresso makers, which differ in the type of pump they employ and how hot the coffee is. There are different ways to control the amount of brew, as well as the size of the cup that can be produced by the machine.

The first espresso machines were steam-types. The earliest espresso machines were steam-type machines. The coffee tasted bitter and burned. The modern espresso machine was developed by the Milanese manufacturers Luigi Bezzerra & Desiderio Pavoni.

The most common espresso machine is a semiautomatic with an electric pump. When people think of espresso machines, they picture these machines. Semi-automatic machines require you to grind and tamp the beans by yourself while the pump controls the flow of water and pressure. This is an excellent combination of human control and mechanised accuracy.

The Filter

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

It also helps with flavor as a filter allows for a more prolonged bloom time. This helps the beans release their nuances and gives an opportunity to improve extraction.

However, it is important to keep in mind that even a high-quality filter can make a terrible cup of coffee, because the quality of the beans and extraction is crucial.

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

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

In recent years, espresso machines powered by a compressed air compressor have become increasingly popular. They utilize an air compressor to force the hot water through the grounds and are more portable than steam-driven electric machines.