9 Things Your Parents Taught You About Machine Espresso > 자유게시판

How Does Machine Espresso Work?

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

Espresso is made by forcing hot water under pressure through finely ground coffee. The process is similar to making drip coffee. However the pressure is the primary difference.

The Group Head

As the name implies, the group head is where you insert your portafilter when making espresso. It disperses water in the portafilter, and then controls the pressure of the extraction. There are a variety of group heads each with their own advantages and espresso and filter coffee machine disadvantages. Some are designed for the stability of temperature while some are specifically designed to handle pre-infusion. Some are designed to control the lever. There are some that include a mix of features, like the E61 that is the standard choice for many baristas due to its capacity to offer multiple benefits in one package.

As you can see in the above photo, the group head has several notches to place your portafilter and then twist it by hand to lock it in. There is also a gasket made from rubber that resides inside the notches and helps to create an airtight seal when you insert your portafilter into the machine. The notches allow for precise placement of the portafilter. This is vital for an even extraction.

The group head not only allows you to put in your portafilter easily however, it also keeps a constant temperature. It does this by cycling hot water through the brew container and around the portafilter, making sure that it's always at the correct temperature to extract. It is important to remember that even a few degree differences can make the distinction between a great and a great espresso.

The Pump

Motorized pumps in espresso machines rotary provide nine atmospheric bar pressure needed to extract espresso. This differs from manual piston machines which use a lever. This pressure is generated by pumping water through a heat exchanger and then through the ground coffee.

Pumps are typically less expensive than piston-driven machines and tend to last longer, however both types of machines could become damaged due to excessive use and poor cleaning. They also add mechanical complexity, which can result in a high price tag on even the most basic models.

Some espresso machines make use of steam pressure instead of a pump to brew espresso. The downside is that the boiler that produces steam also raises the temperature of water to the point of boiling which can cause over-extraction. The machines also need to constantly rebuild their pressure between cups. This takes energy and time.

A majority of barista espresso machine machines utilize the rotary or vibration pump. A vibration model utilizes a vibrating disk to generate pressure, while a Rotary model pushes hot coffee through the ground at a rapid speed. Both machines can make excellent espresso, but rotary machines are more stable, quieter and less likely to fail.

The Boiler

The boiler will heat the water to the perfect temperature for extraction. The steam that is created reaches the portafilter, which holds the espresso grounds. The steam is then channeled into the cup. During this process the steam creates enough pressure to push the grounds of the coffee through. This creates a crema on top of the espresso. This is one of the main characteristics of a good espresso.

There are three kinds of espresso makers, and they differ in the type of pump they use and the degree of heat that the brew is. There are various ways that the brew may be controlled as well as the size of the cup that the machine can produce.

The first espresso machines were steam types. They had one boiler to create both steam and brew, but the pressure they could produce was not very high - two bars of atmospheric pressure at most. The coffee tasted bitter and burnt. This is why the Milanese manufacturers Luigi Bezzerra and Desiderio Pavoni invented the modern espresso machine.

The most popular barista espresso coffee machine machine is a semiautomatic that has an electric pump. These are the things people think of when they think of an espresso machine with frother maker. With a semi-automatic machine, you grind the beans and tamp them yourself but the pump controls the flow of water and pressure. This is a great solution that combines human control with mechanized consistency.

The Filter

Typically, espresso machines utilize filters to separate the coffee grounds as they pass through the hot water. The filter is also a vital component of the machine's temp control, since it helps to prevent overheating.

A filter also helps with flavor because it allows for a longer flowering phase. This allows the beans to release their flavors, and allows for a better extraction.

However, it is important to remember that even a great filter can make a terrible cup of coffee, because the quality of the beans and extraction is crucial.

This is where the magic happens, and it's what makes an espresso really taste good. The grouphead, also called the brew head, is where the portafilter (the container you place the ground coffee into) is located when you're making espresso.

In an espresso machine that is driven by steam, hot water is heated in an airtight container to produce steam, which then pushes the hot water through the grounds under high pressure. These types of machines tend to be cheaper and easier to maintain than pumps-driven models. They are however limited to create the ideal conditions for brewing since they only operate with 1-1.5 bar of pressure. The perfect shot requires 9-10 bars.

In recent times, espresso machines powered by compressed air-pump have become increasingly popular. They utilize an air compressor to force hot water into the grounds and are more portable than steam-driven electric espresso maker machines.