자유게시판

How Does Machine Espresso Work?

Machine espresso uses precision pressure and incredible filter technology to produce the coffee we love. How does it work exactly?

Espresso is produced by pushing hot water at high pressure through finely ground coffee. The process is similar to making drip coffee. However, the pressure is the primary difference.

The Group Head

The group head is the portafilter you put in when making espresso. It is responsible for dispersing the water into the portafilter and controlling the pressure that results from the extraction. There are numerous kinds of group heads, each with its own advantages and disadvantages. Some are designed for stability of temperature while others are built to handle pre-infusion. Some are designed to control the lever. Some include a combination like the E61. This is a favorite among baristas because it offers multiple advantages in a single package.

As you can see in the above image the group head is made up of numerous notches that you can place your portafilter before twisting it manually to secure it. A gasket made of rubber is placed inside the notches to help create a seal when you insert your portafilter. The notches permit the precise placement of the portafilter. This is crucial for an even extraction.

In addition best bean to cup Espresso machine allowing you to effortlessly insert your portafilter the group head is also responsible to maintain an even temperature. This is done by cycling hot water around the portafilter, and through the brew basin, ensuring the temperature is always right to extract the coffee. It is important to note that even a tiny differences can make the distinction between a good and a great espresso.

The Pump

Motorized pumps in rotary espresso machines provide the nine atmospheric bar pressure required to extract espresso machine coffee. This is different from manually operated piston machines that employ levers. This pressure builds up by removing tap water from a reservoir and pumping it through a heat exchanger before being shot through the ground coffee in the group head.

Pumps tend to be less expensive than piston-driven machines and tend to last longer. However, both types of machine can get damaged through overuse and lack of cleaning. Pumps are also more complex mechanically, which could increase prices of even simpler models.

Some espresso machines can eliminate the pump completely and instead make use of steam pressure to make espresso. The disadvantage of this is that the same boiler that produces steam also raises the temperature of water to the point of boiling which could lead to excessive extraction. In addition these machines typically have to rebuild their pressure between cups, which requires time and energy.

Many espresso machines make use of the rotary or vibration pump, with a vibrating model that uses a vibrating disc to create the pressure, and the rotary model pushing hot water through the grounds under high speed. Both machines can make great espresso, however rotary machines are more stable, quieter and less likely to fail.

The Boiler

The boiler is the one that will heat the water to a temperature that is ideal to extract. The resulting steam reaches the portafilter, which contains ground mini espresso maker beans and is then pumped into the cup. During this process the steam causes enough pressure to push the coffee grounds through. This creates a foam on the top of the espresso. This is the hallmark of a good mini espresso machine.

There are three kinds of espresso makers. They differ in the kind of pump they use and how hot the buy espresso machine is. There are various ways that the brew may be controlled as well as the size of the cup that the machine can make.

The first espresso machines were steam-type. They utilized a single boiler to make both steam and brew, but the pressure they could create was minimal - two bars of atmospheric pressure at the most. The coffee tasted bitter and burnt. The modern espresso machine was designed by the Milanese producers Luigi Bezzerra & Desiderio Pavoni.

The most well-known espresso 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 need to grind the beans and then tamp them by hand, but the pump regulates the flow of water and pressure. This is a fantastic solution that combines human control with mechanized reliability.

The Filter

Espresso machines usually use a filter that separates the grounds of the coffee from the hot water. The filter is also an essential component of the machine's temperature control, as it helps prevent overheating.

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

However it is crucial to remember that even a high-quality filter can produce a bad cup of coffee as the quality of the beans and extraction is still important.

This is where the magic happens, it's the thing that makes espresso taste great. The grouphead, also referred to as the brewhead, is where the portafilter (the thing you put the coffee grounds into) is placed when you're making espresso.

Steam-driven espresso machines make use of hot water that is heated in an airtight container to create steam. The steam then pushes hot water through grounds of the coffee under pressure. These machines are cheaper and are easier for the user to maintain than pumps-driven models. They are however limited in their ability for creating the ideal conditions for brewing as they only 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 become more popular. They use an air compressor to force the hot water through the grounds, and are far more portable than steam-driven electric machines.