How Does Machine Espresso Work?

The machine espresso is made using precision pressure, and a filter technology that is awe-inspiring to create the coffee you love. But how exactly does it work?

To make espresso hot water is forced under high pressure through finely ground coffee. The process is similar to making drip coffee but the difference is in the pressure.

The Head of the Group

The name implies, the group head is where you put your portafilter in when making espresso. It is responsible for dispersing water into the portafilter before controlling the pressure that results from the extraction. There are various kinds of group heads, each with their own advantages and disadvantages. Some focus on temperature stability, some on pre-infusion capabilities, while others are designed to control the lever. Some come with a combination of both, such as the E61. This is a very popular choice for baristas since it provides multiple benefits in one package.

As you can see in the image above the group head is fitted with several notches. You can place your portafilter in these notches, then twist the head to lock it. A rubber gasket is located within the notches to create a seal as you insert your portafilter. The notches permit precise placement of the portafilter. This is vital for an even extraction.

The group head is not just able to allow you to put in your portafilter easily, but it also maintains an even temperature. This is achieved by cycling hot water around the portafilter and through the brew basin, ensuring that the temperature is constant to extract the coffee. It is crucial to keep in mind that even a small deviation can make the difference between a good and a excellent espresso.

The Pump

Contrary to manual piston machines which rely on a lever that pressurize water, rotary espresso machines rely on motorized pumps that provide the nine atmospheric bars of pressure required to extract espresso. This pressure is generated by pumping water through a heat exchanger and then through the ground coffee.

Pumps tend to be less expensive than piston-driven machines and tend to last longer. However, both types of machines may be damaged by excessive use and inadequate cleaning. They also add mechanical complexity, which can result in an expensive price for even the simplest models.

Some espresso machines make use of steam pressure instead of a pump in order to brew espresso. This can lead to over-extraction as the boiler that makes steam also heats the water to boil. In addition the machines often have to restore their pressure between cups, which takes time and energy.

Many espresso machines utilize a vibration or rotary pump, with a vibrating model using a rotating disc to create pressure and rotating models that push hot water through the grounds at high speed. Both models 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 is used to heat the water to the perfect temperature for extraction. The steam produced will eventually reach the portafilter, which holds the Espresso Machines Uk (Http://Rutelochki.Ru/User/Closetbay2) grounds. It is then funneled into the cup. The steam is able to create enough pressure to push the grounds of the coffee through. This creates a crema on the top of the professional espresso machine. This is a sign of a great espresso.

There are three distinct types of espresso machines, each having a different type of pump and the temperature of the brew. There are a variety of ways that the brew can be controlled and the size of the cup the machine can make.

The first espresso machines were steam-type. They employed only one boiler to make both brew and steam, however, the pressure they could generate was low - only two bars of atmospheric pressure at most. The coffee tasted bitter and burned. This is why the Milanese makers Luigi Bezzerra and Desiderio Pavoni created the modern espresso machine.

The most commonly used 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 your beans yourself however the pump controls the flow of water and pressure. This is a perfect compromise between human control and mechanized accuracy.

The Filter

Typically, espresso machines have a filter to separate out the grounds of coffee when they pass through the hot water. The filter is also an essential component of the machine's temperature control, since it stops overheating.

It also improves flavor, as a filter allows for a longer bloom phase. This allows the beans to release their flavors and provides an opportunity for a better extraction.

It is important to keep in mind that even the most efficient filter can make a bad cup of coffee. The quality of the beans, and the extraction, are still crucial.

This is where the magic happens, and it's what makes espresso taste great. The grouphead, sometimes referred to as the brew head, is where the portafilter (the thingy you put the ground coffee in) is placed when making espresso.

In the steam-driven espresso machine hot water is heated in an airtight container to produce steam, which then pushes the hot water through the grounds under high pressure. These kinds of machines are generally less expensive and easier to maintain than pumps-driven models. They are however limited to create the ideal brewing conditions as they only 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 across the ground, and are more mobile than steam-driven electric espresso machines.