10 Things That Your Family Taught You About Machine Espresso

How Does Machine Espresso Work?

Machine espresso makes use of precise pressure and amazing filter technology to make the delicious coffee we enjoy. What exactly does it work?

Espresso is created 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 Head of the Group

The group head is the portafilter that you insert when brewing best home espresso machine. It disperses water into the portafilter, and controls the pressure of the extraction. There are a variety of types of group head each with its own advantages and drawbacks. Some focus on temperature stability, others on pre-infusion features, and others are designed to control the lever. There are some that have a combination of features, such as the E61 one, which is the classic choice among many baristas because of its ability to offer multiple benefits in a single package.

As you can see from the image above, the group head is equipped with several notches. You can place your portafilter inside these notches, and then turn the head around to secure it. There is also a rubber gasket that resides inside the notches and helps to create a seal when you insert your portafilter into the machine. The notches allow for precise placement of your portafilter. This is vital for a consistent extraction.

The group head not only lets you to insert your portafilter easily, but it also maintains the temperature at a constant level. This is achieved by cycling hot water around the portafilter, and through the brew-basket, making sure that the temperature is constant to extract the coffee. This is crucial, since just a few degrees could make the difference between a excellent and great buy espresso makers.

The Pump

Unlike manual piston machines, which use a lever to pressurize water, rotary espresso machines rely on motorized pumps that provide the nine atmospheric bars of pressure needed to extract espresso. This pressure builds up by removing tap water from a reservoir, and pumping it through a heat exchanger prior to being pushed through the ground coffee inside the group head.

Pumps tend to be cheaper and last longer than piston-driven machines. However, both types of machines may degrade due to excessive use and insufficient cleaning. Pumps are also more complicated mechanically, which can raise the cost of even the simplest models.

Certain espresso machines remove the pump completely and instead utilize steam pressure to make espresso. This can result in over-extraction because the boiler that makes steam also heats the water to boil. Additionally these machines typically have to rebuild their pressure between cups, which requires time and energy.

Many espresso machines utilize the rotary or vibration pump, with a vibrating model that uses a vibrating disc to generate the pressure, and the rotary model pushing hot water through the grounds at high speed. Both types of machines can make a great commercial espresso machine, but the rotary models are quieter and more durable than vibration pumps.

The Boiler

The boiler is the component which heats the water to the optimal temperature to extract. The steam created reaches the portafilter, which contains the espresso coffee grounds. The steam is then channeled into the cup. The steam creates pressure that pushes through the grounds of the coffee. This creates a crema on the top of the espresso. This is one of the main characteristics of a good espresso.

There are three types of espresso makers. They differ in the type of pump they use and the degree of heat that the espresso is. There are different ways that the brew may be controlled and the size of the cup that the machine can produce.

The first espresso machines were steam-based. They utilized a single boiler to make both brew and steam, however the pressure they were able to produce was very low - just two bars of atmospheric pressure at the most. This resulted in the coffee tasting bitter and burnt. This is the reason Milanese makers Luigi Bezzerra and Desiderio Pavoni developed the modern espresso machine.

The most well-known espresso maker is a semi-automatic machine with an electric pump. When people think of espresso machines, they think of these machines. Semi-automatic machines require you to grind and tamp the beans by yourself however the pump controls the flow of water and pressure. This is a perfect compromise between human control and mechanized reliability.

The Filter

Espresso machines usually have a filter that separates the grounds of coffee from hot water. The filter is also an important element of the temperature control system as it keeps the machine from overheating.

It also improves flavor, as it can allow for a longer bloom time. This allows the beans to release their flavors, and improves extraction.

However it is crucial to keep in mind that even a great filter could result in a bad cup of coffee, as the quality of the beans and extraction are crucial.

It's here that the magic occurs. This is what makes espresso taste so delicious. The grouphead, often called the brewhead, is where the portafilter (the device you put the ground coffee in) is placed when making espresso.

Steam-driven espresso machines use hot water that is heated inside an airtight vessel to create steam. The steam then moves hot water through the grounds of the coffee under pressure. These machines are cheaper and easier to maintain than pumps-driven models. However, they are limited in their ability to create the ideal brewing conditions, since they are only operating at 1-1.5 bars of pressure. The perfect shot requires 9-10 bars.

In recent times, espresso machines powered by compressed air-pump are becoming increasingly popular. They use an air-compressor to force hot water into the ground. They are also more mobile than electric steam-driven espresso machines.