9 . What Your Parents Teach You About Machine Espresso

How Does Machine Espresso Work?

Machine espresso makes use of precise pressure and amazing filter technology to make the delicious coffee we enjoy. But how exactly does it work?

To make espresso hot water is pushed under pressure through finely ground coffee. The process is similar to making drip coffee, but the major difference is in the pressure.

The Head of the Group

The group head is the portafilter that you place in the espresso maker when making it. It disperses water in the portafilter, and then controls the pressure of the extraction. There are various kinds of group head each with its own advantages and disadvantages. Some focus on temperature stability, others on pre-infusion capabilities, while others are designed to control the lever. Some come with a combination of both, such as the E61. This is a very popular choice for baristas as it provides a variety of benefits in a single package.

As you can see in the image above the group head comes with many notches in which you can put your portafilter, then twist it with your hands to lock it in. A rubber gasket is located within the notches to create a seal while you insert your portafilter. The notches on the head allow for an exact placement of the portafilter, Machine espresso which is essential to ensure an efficient extraction.

The group head not only allows 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 at the right level to extract the coffee. It is crucial to keep in mind that even a tiny deviation can make the difference between a great and a great espresso.

The Pump

The motorized pumps that are used in rotary espresso machines provide the nine atmospheric bar pressure that is required for espresso extraction. This differs from manual piston machines that rely on a lever. The pressure is created by drawing tap water from a reservoir, and pumping it through a heat exchanger prior it is shot through the ground coffee inside the group head.

Pumps tend to be cheaper and last longer than piston-driven machines. However, both kinds of machines are susceptible to degrading because of frequent use and Best Ground Coffee For Espresso Machine poor cleaning. Pumps are also more complex mechanically, and can add to the cost of even the simpler models.

Some espresso machines make use of steam pressure instead of a pump to make espresso. This can lead to over-extraction as the boiler that produces steam also causes the water to boil. In addition these machines typically have to restore their pressure between cups, which requires time and energy.

Many espresso machines make use of a vibration or rotary pump, with a vibrating model using a vibrating disc to generate the pressure, and a rotary model pushing hot water through the grounds at high speed. Both machines can produce excellent espresso, but rotary machines are more quiet, durable and less likely to break down.

The Boiler

The boiler is the component that heats the water to the optimal temperature for extraction. The steam produced gets to the portafilter which is a container for espresso grounds. It is then pumped into the cup. During this process the steam generates enough pressure to push the grounds of coffee through. This creates a crema on top of the espresso. This is one of the main characteristics of a good espresso.

There are three types of espresso makers, and Machine espresso they differ in the type of pump they use and the degree of heat that the brew is. There are a variety of ways to control the brew as well as the size of cup that can be produced by the machine.

The first espresso machines for home machines were steam-type. The earliest espresso machines were steam types. This resulted in the coffee tasting burnt and bitter. This is the reason why Milanese makers Luigi Bezzerra and Desiderio Pavoni developed the modern espresso machine.

The most common espresso maker is a semiautomatic machine that has an electric pump. These are the images people have when they think of an espresso maker. Semi-automatic machines require you to grind and tamp your beans yourself while the pump controls the flow of water and pressure. This is an excellent compromise between human touch and the mechanized accuracy.

The Filter

Typically, espresso machines employ filters that separate the grounds of coffee as they move through the hot water. The filter is also an important component of the temperature control system as it prevents the machine from overheating.

It also helps with flavor, as a filter allows for a more prolonged bloom phase. This lets the beans release their flavor and also allows for better extraction.

It is important to remember that even the most efficient filter can make a bad cup of coffee. The quality of the beans, and the extraction process are still crucial.

This is where the magic happens, it's the thing that makes espresso taste good. The grouphead (also known as the brewhead) is where you place the portafilter, which is the thingy used to place the coffee grounds in, when making espresso.

Steam-driven espresso machines make use of hot water that is heated in an airtight vessel to create steam. The steam then moves hot water through the coffee grounds under high pressure. They are less expensive and easier to maintain than pumps-driven models. They are however limited to create 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 hot water through the ground and are much more mobile than electric steam-driven espresso machines.