The Most Sour Advice We've Ever Heard About Machine Espresso

How Does Machine Espresso Work?

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

Espresso is made by pushing hot water under high pressure through finely ground coffee. The process is similar to making drip coffee but the key difference is in the pressure.

The Head of the Group

The group head is the portafilter that is inserted when you are making espresso. It is responsible for Back to the previous page dispersing the water into the portafilter and controlling the pressure of the resulting extraction. There are various kinds of group heads, each with their own advantages and drawbacks. Some are focused on temperature stability, some on pre-infusion options, and others are designed to control the lever. There are even some that include a mix of features, such as the E61, which is considered the most popular choice among baristas due to its capacity to offer multiple benefits in a single package.

As you can see in the image above the group head comes with numerous notches that you can place your portafilter and then twist it with your hands to lock it in. A rubber gasket is located within the notches to create a seal as you insert your portafilter. The notches on the head permit an exact position of the portafilter which is vital to ensure an efficient extraction.

In addition to allowing you effortlessly insert your portafilter the group head is responsible for maintaining an even temperature. It does this by circulating hot water through the brew basket, and around the portafilter, making sure that it is always at the right temperature for extraction. This is important because just a few degrees could be the difference between a excellent and great espresso.

The Pump

Motorized pumps in rotary espresso machines supply the nine atmospheric bar pressure needed to extract espresso. This differs from manual piston machines that rely on levers. This pressure builds up by removing tap water from a reservoir and pumping it through a heat exchanger prior to being shot through the ground coffee in the group head.

Pumps are typically less expensive than piston-driven machines and tend to last longer. However, both types of machine can be damaged by excessive use and inadequate cleaning. They also make mechanically complex, which can result in an expensive price for even the most basic models.

Certain espresso machines utilize steam pressure instead of a pump in order to brew espresso. The disadvantage of this is that the same boiler that produces steam also increases the temperature of water to the point of boiling, which can lead to excessive extraction. Additionally, these machines frequently have to restore their pressure between cups, which requires time and energy.

Many espresso makers machines utilize the rotary or vibration pump, which has a vibration model that uses a vibrating disc to create pressure and an rotary model that pushes hot water through the grounds under high speed. Both machines can make great espresso, but rotary machines are quieter, more durable and less likely to fail.

The Boiler

The boiler is the component which heats the water to the ideal temperature to extract. The steam produced gets to the portafilter which is a container for espresso grounds. It is then funneled into the cup. During this process, steam causes pressure to push through the coffee grounds. This results in a crema on the top of the espresso. This is one of the main characteristics of a good espresso.

There are three kinds of espresso machines, each with different pumps and brew temperature. There are a variety of ways that the brew may be controlled and the dimensions of the cup the machine is capable of making.

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

The most popular espresso maker is a semi-automatic machine with an electric pump. This is what people envision when they think of an espresso maker. Semi-automatic machines require you to grind and tamp the beans by yourself The pump, however, regulates the flow of water and pressure. This is a great compromise between the human touch and the mechanized quality.

The Filter

Typically, espresso machines employ filters to separate the grounds of coffee when they pass through the hot water. The filter is also an essential part of the machine's temperature control, as it helps prevent overheating.

It also enhances flavor, since a filter allows for a more prolonged bloom phase. This allows the beans to release their flavor and gives an opportunity to improve extraction.

It is important to keep in mind that even the most efficient filter can result in a bad cup of coffee. The quality of the beans and the extraction process, remain crucial.

It's in this area that the magic happens. This is the reason why espresso tastes so good. The grouphead (also known as the brewhead) is where you place the portafilter, the thingy that you put the grounds of your coffee into when making espresso.

In a 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 ideal conditions for brewing as they only operate with 1-1.5 bar of pressure. The perfect shot requires 9-10 bars.

In recent years, compressed air pump-driven espresso machines have been gaining popularity. They utilize an air compressor to push hot water through the grounds and are significantly more portable than electric steam-driven machines.