공지사항

How Does Machine Espresso Work?

The machine espresso utilizes precise pressure, as well as a filter technology that is awe-inspiring to create the coffee you love. How exactly does it work?

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

The Head of the Group

The group head is the portafilter is inserted when you are making espresso. It is responsible for dispersing the water into the portafilter and then controlling the pressure of the extraction. There are numerous kinds of group heads each with distinct advantages and drawbacks. Some focus on temperature stability, while others on pre-infusion features, and others are designed to control the lever. There are some that come with a range of features, such as the E61 one, which is the classic choice among many baristas for its ability to provide multiple benefits in one package.

As you can see from the above photo the group head is equipped with several notches. The portafilter is placed inside these notches, and then twist the head to secure it. A gasket of rubber is situated within the notches to create a seal when you insert your portafilter. The notches on the head permit a precise location of the portafilter which is necessary for a consistent extraction.

The group head does not just allow you to insert your portafilter easily, but it also maintains the temperature at a constant level. This is accomplished by cycling hot water around the portafilter and through the brew-basket, making sure that the temperature is constant for extraction. This is vital, because just a few degrees could make the difference between a good and great espresso and filter coffee machine.

The Pump

The motorized pumps in espresso machines rotary provide nine atmospheric bars of pressure required for espresso extraction. This is different from manual piston machines that rely on a lever. The pressure is created by pumping water through a heat exchanger and then through the ground coffee.

Pumps are generally more affordable and last longer than piston-driven machines. However, both kinds of machines may degrade because of frequent use and poor cleaning. Pumps are also more complex mechanically, which could increase the cost of even the simple models.

Some espresso machines use steam pressure instead of a pump for brewing espresso. The downside is that the boiler that produces steam also increases the temperature of water to the point of boiling which can cause excessive extraction. The machines must also constantly rebuild their pressure between cups. This takes energy and time.

A majority of espresso machines use a vibration or rotary pump, with a vibration model using a rotating disc to create the pressure and an rotary model that pushes hot water through the grounds at high speed. Both machines produce great espresso, however rotary machines are quieter, more durable and less likely to break.

The Boiler

The boiler is the part that heats the water to the ideal temperature for extraction. The steam that is created is then directed to the portafilter, which is the container that holds the espresso coffee grounds. It is then pumped into the cup. During this process, the steam creates pressure and pushes through the coffee grounds. This results in a crema on top of the espresso. This is the hallmark of a great espresso.

There are three kinds of espresso makers, and they differ in the kind of pump they use and how hot the coffee is. There are a variety of ways to control the brew as well as the size of the cup that can be produced by the machine.

The first espresso machines were steam-types. They utilized one boiler to make both steam and brew, however, the pressure they could generate was low - only two bars of atmospheric pressure maximum. This resulted in the coffee espresso machines tasting burnt and bitter. This is why the Milanese manufacturers Luigi Bezzerra and espresso and filter coffee machine Desiderio Pavoni developed the modern espresso machine.

The most well-known espresso machine is a semiautomatic model with an electric pump. When people think of espresso machines, they envision these machines. With a semi-automatic espresso machine, you have to grind the beans and tamp them yourself but the pump is able to regulate the flow of water and pressure. This is an excellent combination of human control and mechanised accuracy.

The Filter

Typically, espresso machines employ a filter to separate out the grounds of coffee when they pass through the hot water. The filter is also a vital part of the machine's temperature control, since it helps to prevent overheating.

It also aids in flavor, as a filter allows for a longer bloom phase. This helps 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 result in a bad cup of coffee. The quality of the beans, and the extraction process remain crucial.

This is where the magic happens. It's what makes espresso taste good. The grouphead (also called the brewhead) is where you place the portafilter - the thingy that you use to put the grounds of your coffee into when 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 with high pressure. These kinds of machines are typically cheaper and easier to maintain than pump-driven models. They are however limited in their ability to create the ideal conditions for brewing, as they 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 been gaining popularity. They utilize an air compressor to push hot water across the ground and are more mobile than electric steam-driven espresso machines.