자유게시판

How Does Machine Espresso Work?

Machine espresso employs precise pressure and mind-blowing filter technology to make the delicious coffee we enjoy. What exactly is it?

Espresso is made by pushing hot water under pressure through finely ground coffee. The process is similar to making drip coffee however the main difference lies in the pressure.

The Head of the Group

As the name implies the group head is the place you put your portafilter in when making espresso. It is responsible for dispersing water into the portafilter before controlling the pressure of the resulting extraction. There are many different kinds of group head each with its particular advantages and drawbacks. Some focus on temperature stability, others on pre-infusion options, and others are designed to control the lever. There are also some that come with a range of features, such as the E61, which is considered the standard choice for many baristas because of its ability to provide multiple benefits in a single package.

As you can see in the image above The group head features many notches in which you can place your portafilter and then twist it by hand to secure it. A gasket made of rubber is positioned inside the notches to help create a seal when you insert your portafilter. The notches on the head allow for an exact positioning of the portafilter which is necessary for an efficient extraction.

In addition to allowing you easily connect your portafilter, the group head is also responsible to ensure that the temperature remains even. This is accomplished by cycling hot water around the portafilter and through the brew basin, ensuring that the temperature is at the right level to extract the coffee. This is crucial, since even a few degrees can make the difference between a excellent and great espresso.

The Pump

The motorized pumps used in espresso machines rotary provide nine atmospheric bars of pressure required for espresso extraction. This is different from manual piston machines that use a lever. The pressure builds up by drawing tap water from a reservoir and pumping it through a heat exchanger prior being pushed through the ground coffee in the group head.

Pumps are typically less expensive than piston-driven machines and tend to last longer, but both types of machines can degrade with overuse and insufficient cleaning. Pumps are also more complicated mechanically, which can increase the price of even the simplest models.

Some espresso machines employ steam pressure instead of a pump to make espresso machine with milk frother. This can result in over-extraction because the boiler that produces steam also warms the water to boil. Additionally these machines are often required to rebuild their pressure between cups, which takes time and energy.

Many espresso machines use an rotary or a vibration pump. A vibration model utilizes a rotating disk to generate pressure, whereas a circular model pushes hot liquid through the ground at a rapid speed. Both types of machines are capable of producing excellent espresso, but Rotary machines are quieter and more durable than vibration pumps.

The Boiler

The boiler is what will heat the water to the right temperature for extraction. The resultant steam then reaches the portafilter which holds the ground espresso coffee, and is then pumped down into the cup. The steam is able to create enough pressure to push the grounds of coffee through. This produces a layer of crema on top. This is one of the main characteristics of a good best espresso machine uk.

There are three kinds of espresso machines, each with a different type of pump and brew temperature. There are a variety of ways to control the strength of the brew and the size of cup that can be made by the machine.

The first espresso machines were steam-type. They employed only one boiler to make both steam and brew however, the pressure they could create was minimal - two bars of atmospheric pressure at most. The coffee tasted bitter and burned. The modern espresso machine was created by the Milanese makers Luigi Bezzerra & Desiderio Pavoni.

The most well-known espresso machine is a semiautomatic with an electric pump. These are the things people think of when they think of an espresso maker. Semi-automatic machines require you to grind and tamp the beans on your own however the pump controls the water flow and pressure. This is a great combination of human control and mechanized consistency.

The Filter

Typically, espresso machines have a filter to separate out the grounds of the coffee as they go through the hot water. The filter is also an essential part of the machine's temperature control, since it helps to prevent overheating.

A filter also helps with flavor, as it permits the beans to flower for a longer period of time. This helps the beans release their nuances and gives an opportunity for a better extraction.

However it is crucial to keep in mind that even a top filter could result in a bad cup of coffee, because the quality of the beans and extraction is still vital.

It's in this area that the magic happens. This is what makes espresso taste so delicious. The grouphead (also known as the brewhead) is where you place the portafilter, the device that you use to put the grounds of your coffee into while making espresso coffee machines.

Steam-driven italian espresso machines machines use hot water that is heated in an airtight container to make steam. The steam then moves hot water through the grounds of coffee at high pressure. These machines are cheaper and easier for the owner to maintain than pumps-driven models. However, they are not as efficient in their capacity to create the ideal conditions for brewing because they operate at 1-1.5 bars of pressure, while the perfect shot requires 9 bar espresso machine-10 bars.

In recent times, espresso machines powered by compressed air-pump are becoming increasingly popular. They utilize an air compressor to push hot water through the ground, and are more mobile than electric steam-driven espresso machine small machines.