A Provocative Remark About Machine Espresso > 자유게시판

How Does Machine Espresso Work?

Machine espresso employs precise pressure and mind-blowing filter technology to make the perfect cup of coffee. What exactly does it work?

In order to make espresso, hot water is pushed under 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 you insert when brewing uk espresso machine. It is responsible for dispersing water into the portafilter and controlling the pressure of the extraction. There are many different kinds of group heads, each with their particular advantages and disadvantages. Some are focused on temperature stability, whereas others on pre-infusion features, and others are designed to control the lever. Some come with a combination of both, like the E61. This is a popular choice among baristas because it offers multiple advantages in a single package.

As you can see in the above photo the group head is made up of several notches to put your portafilter, then twist it manually to secure it. A rubber gasket is located in the notches to create a seal while you insert your portafilter. The notches permit the precise placement of the portafilter. This is essential for an accurate extraction.

The group head does not just allow you to place your portafilter easily however it also keeps an even temperature. This is done by cycling hot water around the portafilter and through the brew-basket, ensuring the temperature is always right for extraction. This is vital, because even a small difference in temperature can mean the difference between good and excellent espresso.

The Pump

Unlike manual piston machines, which rely on a lever that pressurize water, rotating espresso machines rely upon motorized pumps to provide the nine atmospheric bars of pressure that are required for espresso extraction. This pressure is built up by pumping water through a heat exchanger and then through the ground coffee.

Pumps are typically less expensive and last for longer than piston-driven machines. However, both types of machines can degrade because of frequent use and poor cleaning. They also make mechanically complex, which can result in a high price tag on even the simplest models.

Some espresso machines remove the pump entirely and utilize steam pressure to make espresso. This can cause over-extraction because the boiler that produces steam also warms the water to boil. These machines also have to continuously rebuild their pressure between cups. This takes energy and time.

A majority of espresso machines use the rotary or vibration pump, with a vibration model using a vibrating disc to generate the pressure, and an rotary model that pushes hot water through the grounds at high speed. Both models are capable of producing excellent espresso, however the rotary models are quieter and more durable than vibration pumps.

The Boiler

The boiler will heat the water to the ideal temperature to extract. The resulting steam reaches the portafilter containing the ground espresso coffee and gets funnelled down into the cup. The steam causes enough pressure to push the grounds of the coffee through. This results in a layer crema that is then poured over. This is the hallmark of a great espresso.

There are three kinds of espresso machines, each having a different type of pump and the temperature of the brew. There are different ways in which the brew could be controlled, as well as the size of the cup the machine can make.

The first espresso machines were steam-types. They employed a single boiler to make both brew and steam, but the pressure they could create was minimal - two bars of atmospheric pressure at the most. The coffee tasted bitter and burnt. This is the reason why Milanese manufacturers Luigi Bezzerra and Desiderio Pavoni created the modern espresso machine.

The most popular retro espresso maker machine is a semiautomatic with an electric pump. These are what people imagine when they think of an espresso machine. With a semi-automatic machine you grind the beans and then tamp them yourself but the pump controls the flow of water and pressure. This is an excellent compromise between human touch and the mechanized consistency.

The Filter

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

A filter also helps with flavor, as it permits a longer flowering period. This allows the beans to release their flavors and provides an opportunity for better extraction.

However, it is important to remember that even a good filter can produce a bad cup of coffee, as the quality of the beans and extraction is vital.

This is where the magic happens, and it's what makes an top espresso machines really taste good. The grouphead (also called the brewhead) is where you place the portafilter, which is the thingy used to place the grounds of coffee into when making espresso.

Steam-driven espresso machines make use of hot water that is heated inside an airtight vessel to create steam. The steam then pushes hot water through grounds of the coffee under pressure. These machines are less expensive and easier for the user to maintain than pumps-driven models. They are however limited in their ability for creating the ideal conditions for brewing since they only operate with 1-1.5 9 bar espresso machine of pressure. The ideal shot requires 9 Bar Espresso Machine-10 bars.

In recent years, espresso machines powered by compressed air-pump have become increasingly popular. They utilize an air compressor to push hot water across the ground and are more mobile than electric steam-driven espresso machines.