12 Machine Espresso Facts To Bring You Up To Speed The Cooler Water Co…

How Does Machine Espresso Work?

Machine espresso makes use of precise pressure and mind-blowing filter technology to make the perfect cup of coffee. How does it work exactly?

To make espresso hot water is forced under high pressure through finely ground coffee. The process is similar to that of making drip coffee. However it is the pressure that makes the main difference.

The Head of the Group

The name implies the group head is the place you place your portafilter when brewing espresso. It is responsible for dispersing water into the portafilter and then controlling the pressure that results from the extraction. There are numerous kinds of group heads each with distinct 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 as it provides a variety of advantages in a single package.

As you can see in the above photo, the group head is fitted with a variety of notches. You place your portafilter into these notches and twist the head to lock it. There is also a gasket of rubber that resides inside the notches and helps to create a seal when you insert your portafilter into the machine. The notches on the head allow for an exact positioning of the portafilter which is vital to ensure an efficient extraction.

Aside from allowing you to easily insert your portafilter, the group head is responsible for maintaining an even temperature. This is achieved 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, as just a few degrees could make the difference between good and great espresso.

The Pump

In contrast to manual piston machines which rely on a lever that pressurize water, the rotary espresso machines use motorized pumps to supply the nine atmospheric bars of pressure required for espresso extraction. The pressure is built by pumping water through a heat-exchanger and then through the ground coffee.

Pumps are generally less expensive than piston-driven machines and tend to last longer. However, both types of machines may get damaged through overuse and lack of cleaning. They also make mechanically complex and can lead to an expensive price for even the simplest models.

Some espresso machines remove the pump entirely and utilize steam pressure to make portable espresso machine. This can lead to over-extraction as the boiler that makes steam also heats the water until it comes to a boil. Additionally, these machines frequently have to restore their pressure between cups, which takes time and energy.

Many espresso machines utilize the rotary or vibration pump, which is a vibration model using a rotating disc to create the pressure, and an rotary model that pushes hot water through the grounds under high speed. Both machines produce great espresso, however rotary machines are more stable, quieter and less likely to break.

The Boiler

The boiler is what is used to heat the water to the perfect temperature to extract. The steam that is produced will eventually reach the portafilter, which contains the espresso coffee grounds. It is then pumped into the cup. During this process, steam causes pressure to push through the grounds of the coffee. This produces a layer of crema on top. This is one of the main characteristics of a great espresso.

There are three types of espresso makers, and they differ in the kind of pump they use and the degree of heat that the espresso is. There are various ways in which the brew could be controlled, as well as the size of the cup the machine is capable of making.

The first espresso machines were steam-type. They used one boiler to make both steam and brew, however the pressure they were able to produce was not very high - two bars of atmospheric pressure maximum. This led to the coffee tasting burnt and bitter. This is why the Milanese makers Luigi Bezzerra and Desiderio la pavoni espresso machine created the modern portable espresso maker machine.

The most well-known espresso maker is a semi-automatic device that has an electric pump. When people think of espresso machines, they picture these machines. Semi-automatic machines require you to grind and tamp the beans yourself however the pump controls the water flow and pressure. This is an excellent compromise between human control and mechanised consistency.

The Filter

Espresso machines typically use a filter that separates the grounds of the coffee from hot water. The filter is also an essential part of the machine's temperature control, as it prevents overheating.

Filters also aid in flavor because it allows for the beans to flower for a longer period of time. This allows beans to let their nuances out and provides an opportunity for a better extraction.

However, it is important to keep in mind that even a high-quality filter could result in a bad cup of coffee, delonghi espresso maker because the quality of the beans and extraction are important.

This is where the magic happens, and it's what makes an espresso really taste great. The grouphead, sometimes referred to as the brew head, is where the portafilter (the device you put the coffee ground into) is located when you're making breville bijou espresso machine.

Steam-driven delonghi espresso maker machines use hot water that is heated in an airtight vessel to create steam. The steam then moves hot water through the grounds of coffee under high pressure. These machines are cheaper and easier for the owner to maintain than pumps-driven models. They are however limited in their ability for creating the ideal brewing conditions as they only operate with 1-1.5 bar of pressure. The perfect shot requires 9-10 bars.

In recent years, compressed air-driven espresso machines have become more popular. They use an air compressor to force hot water through the ground and are much more mobile than steam-driven electric espresso maker espresso machines.