9 Lessons Your Parents Taught You About Machine Espresso

How Does Machine Espresso Work?

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

Espresso is made by pushing hot water at high 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 name implies the group head is the place you place your portafilter while making espresso. It disperses the water into the portafilter, and then controls the pressure of the extraction. There are a variety of types of group head each with its particular advantages and disadvantages. Some are specifically designed for temperature stability while others are specifically designed to handle pre-infusion. Some are designed to control the lever. There are even some that contain a variety of features, like the E61 one, which is the most popular choice among baristas due to its capacity to offer multiple benefits in one package.

As you can see in the image above the head of the group is equipped with several notches. The portafilter is placed in these notches, then turn the head around to secure it. A rubber gasket is located inside the notches, which helps create a seal as you insert your portafilter. The notches allow for the precise placement of the portafilter. This is crucial to ensure an even extraction.

Aside from allowing you to effortlessly insert your portafilter the group head is responsible to maintain an even temperature. This is accomplished by cycling hot water around the portafilter, and through the brew basin, ensuring that the temperature is constant to extract the coffee. This is important because even a small difference in temperature can make the difference between good and great espresso.

The Pump

Motorized pumps in commercial espresso machine machines rotary provide nine atmospheric bars of pressure required to extract espresso. This differs from manual piston machines that use levers. The pressure builds by drawing tap water from a reservoir, and pumping it through a heat exchanger before being pumped through the ground coffee in the group head.

Pumps are typically more affordable and last longer than piston-driven machines. However, both kinds of machines may degrade due to excessive use and poor cleaning. They also increase the complexity of mechanical systems which can result in an expensive price for even the simplest models.

Some espresso machines employ steam pressure instead of a pump to make espresso. The downside is that the same boiler that produces steam also raises the temperature of water to boiling which could lead bean to cup espresso machines over-extraction. In addition the machines often have to rebuild their pressure between cups, which requires time and energy.

Many espresso machines use a rotary or vibration pump. A vibration model utilizes the vibrating disk to create pressure, whereas the rotating model pushes hot water through the ground at a fast speed. Both types of machine can produce an excellent espresso, however the rotary models are quieter and more durable than vibration pumps.

The Boiler

The boiler is the part that heats water to an optimal temperature to extract. The steam that is produced reaches the portafilter, which is the container that holds the espresso coffee grounds. It is then pumped into the cup. During this process, the steam creates pressure that pushes through the grounds of the coffee. This creates a crema on the top of the espresso. This is one of the hallmarks of a great espresso.

There are three kinds of espresso makers, and they differ in the type of pump they use and the degree of heat that the retro espresso machine 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 earliest espresso machines were steam types. This led to the coffee tasting bitter and burnt. The modern espresso machine was invented by the Milanese makers Luigi Bezzerra & Desiderio Pavoni.

The most commonly used espresso machine is a semiautomatic that has an electric pump. When people think of espresso machines, they envision these machines. Semi-automatic machines espresso require you to grind and tamp the beans yourself however the pump controls the flow of water and pressure. This is an excellent compromise between human touch and the mechanised quality.

The Filter

Espresso machines typically have a filter that separates 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 can also help with flavor since it allows for a longer flowering phase. This helps the beans to let their nuances out and provides the chance for better extraction.

However, it is important to remember that even a good filter can produce a bad cup of coffee, as the quality of the beans and extraction is still important.

It's in this area that the magic takes place. This is the reason why espresso tastes so delicious. The grouphead (also known as the brewhead) is where you place the portafilter - the thingy that you use to put the coffee grounds in, when making espresso.

In an espresso machine that is driven by steam, hot water is heated in an airtight container to create steam. This then pushes the hot water through the grounds under high pressure. These types of machines tend to be cheaper and easier to maintain than pumps-driven models. However, they are limited in their ability to provide the ideal conditions for brewing since they operate at 1-1.5 bars of pressure. However, the perfect shot requires 9-10 bar.

In recent years, espresso maker for home machines powered by compressed air-pump are becoming increasingly popular. They use an air compressor to push hot water through grounds, and are far more portable than steam-driven electric machines.