• 목록
• 답변
• 글쓰기
• 게시판 리스트 옵션
  • 수정
  • 삭제

How Does Machine Espresso Work?

Machine espresso employs precise pressure and amazing filter technology to make the coffee we love. What exactly is it that makes it work?

espresso coffee machine for home is produced by pushing hot water under pressure through finely ground coffee. The process is similar to making drip coffee, but the key difference is in the pressure.

The Group Head

The group head is the portafilter is inserted when you are making espresso. It disperses the water into the portafilter, and regulates the pressure during the extraction. There are many different kinds of group heads each with its unique advantages and disadvantages. Some focus on temperature stability, some on pre-infusion features, and others are designed to control the lever. There are even some that contain a variety of features, such as the E61 one, which is the classic choice among many baristas due to its capacity to offer multiple benefits in a single package.

As you can see in the picture above, the group head is fitted with several notches. You place your portafilter in these notches and then twist the head to lock it. There is also a gasket made from rubber that resides inside the notches to help create an airtight seal when you insert your portafilter into the machine. The notches on the head permit a precise positioning of the portafilter which is necessary to ensure an even extraction.

Aside from allowing you to easily place your portafilter in, the group head is also responsible for maintaining a consistent temperature. It does this by circulating hot water through the brew pan and around the portafilter, ensuring that it's always at the right temperature to extract. This is vital, because even a small difference in temperature can make the difference between a excellent and great espresso.

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 for espresso extraction. 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 than piston-driven machines and tend to last longer, although both types of machine can become damaged due to excessive use and poor cleaning. Pumps are also more complex mechanically, which can increase the price of even the simple models.

Some espresso machines remove the pump completely and make use of steam pressure to make espresso. The drawback of this is that the boiler that produces steam also raises the temperature of the water to boiling which could lead to excessive extraction. Additionally the machines often have to restore their pressure between cups, which takes time and energy.

A large majority of decent espresso machine machines employ the rotary or vibration pump. A vibration model makes use of a rotating disk to generate pressure, while the Rotary model pushes hot coffee through the ground at a rapid speed. Both machines can make excellent espresso however rotary machines tend to be more stable, quieter and less likely to break.

The Boiler

The boiler is what is used to heat the water to the right temperature for extraction. The steam that is created gets to the portafilter which contains the espresso coffee grounds. It is then poured into the cup. During this process, steam creates pressure to push through the grounds of the coffee. This results in a layer of crema on top. This is one of the hallmarks of a good espresso.

There are three different types of espresso machines, each having different types of pumps and brew temperature. There are many ways to control the brew as well as the size of cup that can be made by the machine.

The first retro espresso machine machines were steam-type. The first espresso machines were steam-type machines. The coffee tasted bitter and burnt. The modern espresso machine was invented by the Milanese producers Luigi Bezzerra & Desiderio Pavoni.

The most common espresso machine is a semiautomatic model with an electric pump. When people think of espresso machines, they imagine these machines. Semi-automatic machines require you to grind and tamp the beans by yourself, but the pump regulates the water flow and pressure. This is a great solution that combines human control with mechanized consistency.

The Filter

Espresso machines usually have a filter that separates the grounds of the coffee from the hot water. The filter is also a vital part of the temperature control system since it helps prevent the machine from overheating.

It also aids in flavor, as it allows for a more prolonged bloom phase. This lets the beans release their flavors, and allows for a better extraction.

However, it is important 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 essential.

It's in this area that the magic happens. This is the reason why espresso tastes so good. The grouphead, machine espresso sometimes called the brew head, is the place where the portafilter (the thing you put the ground coffee into) sits when you're making espresso.

Steam-driven espresso machines make use of hot water heated in an airtight container to produce steam. The steam then pushes hot water into the grounds of the coffee under pressure. These machines are cheaper and easier for the user to maintain than pumps-driven models. However, they are not as efficient in their ability to create the perfect conditions for brewing, since they are only operating at 1-1.5 bars of pressure, while the perfect shot requires 9-10 bar.

In recent years, espresso machines driven by compressed air-pump have become increasingly popular. They use an air compressor to push hot water into the grounds, and are far more portable than steam-driven electric machines.