Machine Espresso: The Ugly Facts About Machine Espresso > 자유게시판

How Does Machine Espresso Work?

Machine espresso utilizes precise pressure and mind-blowing filter technology to create the perfect cup of coffee. How exactly does it work?

To make an espresso, hot water is forced under high pressure through finely ground coffee. The process is similar to making drip coffee however the main difference lies in the pressure.

The Group Head

The name implies, the group head is where you place your portafilter while brewing espresso. It is responsible for dispersing the water into the portafilter, and controlling the pressure of the extraction. There are a variety of group heads each with their own advantages and disadvantages. Some are focused on temperature stability, others on pre-infusion capabilities, while others are designed to control the lever. Some come with a combination of both, like the E61. This is a popular choice among baristas since it provides multiple benefits in one package.

As you can see in the above photo The group head features several notches to place your portafilter and twist it manually to lock it in. A gasket made of rubber is positioned in the notches to make a seal when you insert your portafilter. The notches permit an exact placement of the portafilter. This is vital for an even extraction.

The group head is not just able to allow the portafilter to be inserted easily however, it also keeps a constant temperature. This is done by cycling hot water around the portafilter, and through the brew basin, ensuring that the temperature is always at the right level to extract the coffee. It is crucial to keep in mind that even a small difference can make the difference between a decent and a excellent espresso.

The Pump

The motorized pumps in espresso machines that rotate provide the nine atmospheric bar pressure required for espresso machine with milk frother extraction. This differs from manual piston machines that rely on 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 they tend to last longer. However, both types of machines could degrade with overuse and insufficient cleaning. Pumps are also more complex mechanically, which can raise prices of even simpler models.

Some espresso machines can eliminate the pump completely and make use of steam pressure to make espresso. The drawback is that the same dual boiler espresso machine that produces steam also increases the temperature of the water until it reaches boiling which could lead to over-extraction. Additionally these machines typically have to rebuild their pressure between cups, which requires time and energy.

Many espresso machines make use of either a rotary or vibration pump, which has a vibration model using a rotating disc to generate the pressure, and rotating models that push hot water through the grounds under high speed. Both types of machine are capable of producing excellent espresso, however the rotary models are quieter and more durable than vibration pumps.

The Boiler

The boiler is the part which heats the water to the optimal temperature to extract. The steam that is produced reaches the portafilter, which is a container for espresso grounds. It is then funneled into the cup. The steam causes enough pressure to push the grounds of coffee through. This creates a foam on top espresso machines 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 how hot the espresso is. There are various ways to control the brew and the size of the cup that can be produced by the machine.

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

The most commonly used espresso machine is a semiautomatic that has an electric pump. This is what people envision when they imagine an espresso machine. Semi-automatic machines require you to grind and tamp the beans by yourself, but the pump regulates the flow of water and pressure. This is an excellent compromise between human touch and the mechanized quality.

The Filter

Typically, Best espresso machine under 200 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 temperature control system because it stops the machine from overheating.

It also helps with flavor, as it can allow for a longer bloom time. This lets the beans release their flavors, and allows for better extraction.

However it is crucial to remember that even a great filter can result in a poor cup of coffee as the quality of the beans and extraction is important.

It's here that the magic occurs. This is the reason why espresso tastes so good. The grouphead, sometimes called the brew head, is the place where the portafilter (the container you place the coffee ground into) is located when you're making espresso.

In a steam-driven espresso machine hot water is heated in an airtight container to produce steam, which is then pushed through the grounds under high pressure. They are less expensive and are easier for the user to maintain than pumps-driven models. They are however limited to create the perfect conditions for brewing, as they operate with 1-1.5 bar of pressure. The ideal shot requires 9-10 bars.

In recent years, compressed air-driven espresso machines have become more popular. They utilize an air compressor to force the hot water through the grounds, and are far more portable than electric steam-driven machines.