How To Resolve Issues With Machine Espresso

How Does Machine Espresso Coffee Machine With Milk Frother Work?

Machine pro espresso machine employs precise pressure and incredible filter technology to produce the delicious coffee we enjoy. How exactly does it work?

Espresso is produced by pushing hot water 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

As the name suggests, the group head is the place you place your portafilter when brewing espresso. It is responsible for dispersing water into the portafilter and then controlling the pressure that results from the extraction. There are numerous kinds of group heads each with distinct advantages and disadvantages. Some are focused on temperature stability, while others on pre-infusion features, and others are designed to control the lever. Some include a combination such as the E61. This is a popular choice among baristas as it provides a variety of advantages in one package.

As you can see in the photo above the group head has a number of notches. It is possible to place your portafilter into these notches and twist the head to lock it. A gasket made of rubber is positioned inside the notches, which helps create a seal while you insert your portafilter. The notches on the head permit a precise location of the portafilter which is crucial to ensure an even extraction.

In addition to allowing you to effortlessly insert your portafilter the group head is also responsible for maintaining an even temperature. This is achieved by cycling hot water around the portafilter, and through the brew basin, ensuring that the temperature is at the right level for extraction. It is important to note that even a few degree difference can make the difference between a decent and a excellent espresso.

The Pump

Contrary to manual piston machines which rely on a lever to pressurize water, rotary espresso machines rely on motorized pumps to supply the nine atmospheric bars of pressure necessary for espresso extraction. The pressure builds by drawing tap water from a reservoir, and pumping it through a heat exchanger before it is shot through the ground coffee in the group head.

Pumps tend to be cheaper than piston-driven machines, and tend to last longer. However, both types of machines may get damaged through overuse and lack of cleaning. Pumps are also more complicated mechanically, and can add to the cost of even simpler models.

Some espresso machines use steam pressure instead of a pump for brewing espresso. This can result in over-extraction because the boiler that makes steam also warms the water to boil. In addition these machines are often required to rebuild their pressure between cups, which requires time and energy.

A majority of espresso machines use the rotary or vibration pump, with a vibrating model using a vibrating disc to create the pressure and rotating models that push hot water through the grounds under high speed. Both models are capable of producing excellent espresso, but Rotary machines are quieter and more durable than vibration pumps.

The Boiler

The boiler is the part that heats the water to the ideal temperature to extract. The steam produced reaches the portafilter, which holds the espresso grounds. It is then pumped into the cup. In this process, the steam causes pressure to push through the coffee grounds. This results in a layer of crema that is then poured over. This is one of the main characteristics of a good espresso.

There are three kinds of espresso machines, each having a different type of pump and the temperature of the brew. There are a variety of ways that the brew may be controlled, as well as the size of the cup the machine is capable of making.

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

The most popular espresso machine is a semiautomatic one with an electric pump. When people think of espresso machines home machines, they envision these machines. With a semi-automatic machine you must grind the beans and tamp them by hand. However, the pump regulates the flow of water and pressure. This is a great compromise between human control and mechanised reliability.

The Filter

Typically, espresso machines employ filters to separate the grounds of the coffee as they go through the hot water. The filter is also an essential component of the machine's temperature control, since it stops overheating.

It also enhances flavor as a filter allows for a longer bloom phase. This allows the beans to release their flavors, and allows for better extraction.

It is important to keep in mind that even the best filter can produce a bad cup of coffee espresso machine. The quality of the beans as well as the extraction, are still very important.

This is where the magic happens, it's the thing that makes espresso taste good. The grouphead, also called the brewhead, is where the portafilter (the container you place the ground coffee into) is located when you're making espresso.

In the steam-driven espresso machine hot water is heated in an airtight tank to create steam. This then pushes the hot water through the grounds with 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 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 utilize an air compressor to push the hot water through the grounds and are significantly more portable than electric steam-driven machines.