How Does Machine Espresso Work?

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

In order to make espresso hot water is pushed under pressure through finely ground coffee. The process is similar to making drip coffee. However the pressure is the primary difference.

The Group Head

The name implies, the group head is where you put your portafilter in when making espresso. It is responsible for dispersing the water into the portafilter, and controlling the pressure of the extraction. There are many different kinds of group heads, each with their particular advantages and drawbacks. Some are designed for the stability of temperature while some are built to handle pre-infusion. Others are made to control the lever. There are some that include a mix of features, such as the E61, which is considered the most popular choice among baristas because of its ability to provide multiple benefits in a single package.

As you can see in the image above, the group head is equipped with several notches. You place your portafilter in these notches and then twist the head to lock it. A gasket of rubber is situated in the notches to make a seal when you insert your portafilter. The notches permit precise placement of your portafilter. This is crucial for an accurate extraction.

The group head is not just able to allow you to insert your portafilter easily but also maintains a constant temperature. This is done by cycling hot water around the portafilter, and through the brew-basket, making sure the temperature is always right to extract the coffee. It is important to note that even a few degree variation can mean the difference between a good and great espresso.

The Pump

Unlike manual piston machines, which rely on a lever to pressurize water, the rotary espresso machines use motorized pumps to supply the nine atmospheric bars of pressure that are required to extract espresso. The pressure is created by pumping water through a heat exchanger and then through the ground coffee.

Pumps tend to be cheaper than piston-driven machines, and they tend to last longer. However, both types of machines may be damaged by excessive use and inadequate cleaning. Pumps are also more complex mechanically, which could increase the cost of even the simple models.

Some espresso machines employ steam pressure instead of a pump in order to brew espresso Machines home. The disadvantage of this is that the same boiler that produces steam also increases the temperature of the water until it reaches boiling which could lead to excessive extraction. These machines also have to continuously rebuild their pressure between cups. This requires energy and time.

Many espresso machines utilize either a rotary or vibration pump, with a vibrating model that uses a vibrating disc to create pressure and the rotary model pushing hot water through the grounds under high speed. Both types of machines can produce an excellent espresso, however Rotary machines are quieter and more durable than vibration pumps.

The Boiler

The boiler is what is used bean to cup espresso machines heat the water to a temperature that is ideal for extraction. The resulting steam is then transferred to the portafilter that contains the ground espresso and is then pumped into the cup. The steam creates pressure and pushes through the grounds of the coffee. This results in a crema on the top of the espresso. This is a sign of a great espresso.

There are three different types of espresso machines, each with distinct pumps and the temperature of the brew. There are many ways to control the amount of brew, as well as the size of cup that can be made by the machine.

The earliest espresso machines were steam-based. The first espresso machines were steam types. The coffee machines espresso tasted bitter and burned. The modern cafe espresso machine machine was created by the Milanese manufacturers Luigi Bezzerra & Desiderio Pavoni.

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

The Filter

Espresso machines typically use filters that separate the coffee grounds from the hot water. The filter is also an essential element of the machine’s temperature control, since it stops overheating.

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

It is important to keep in mind that even the finest filter could result in a poor cup of coffee machine espresso. The quality of the beans and the extraction process, are still very important.

This is where the magic happens, it’s the thing that makes espresso taste great. The grouphead (also called the brewhead) is where you place the portafilter, the device that you put the grounds of coffee into when making espresso.

In a steam-driven espresso machine hot water is heated in an airtight container to create steam. This then pushes the hot water through the grounds at high pressure. They are less expensive and easier for the owner to maintain than pumps-driven models. However, they are not as efficient in their ability to provide the perfect brewing conditions because they operate at 1-1.5 bars of pressure, while the perfect shot requires 9-10 bar.

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 much more portable than steam-driven electric machines.