The 9 Things Your Parents Teach You About Machine Espresso

How Does Machine Espresso Work?

Machine espresso uses precision pressure and incredible filter technology to produce the coffee we love. What exactly is it?

Espresso is made by forcing 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 Head of the Group

The group head is the portafilter you insert when brewing espresso. It disperses the water into the portafilter and regulates the pressure of extraction. There are a variety of group heads each with distinct advantages and drawbacks. Some are designed for stability in temperature, while others are designed to handle pre-infusion. Others are made to control the lever. Some have a combination, like the E61. This is a preferred choice for baristas since it provides multiple advantages in one package.

As you can see from the above photo the group head is fitted with several notches. You place your portafilter inside these notches, and then twist the head to lock it. A gasket made of rubber is positioned inside the notches, which helps create a seal when you insert your portafilter. The notches allow for the precise placement of the portafilter. This is vital for an efficient extraction.

In addition to allowing you easily connect your portafilter, the group head is responsible to ensure that the temperature remains even. It does this by circulating hot water through the brew pan and around the portafilter to ensure that it's always at the right temperature to extract. This is important because even a few degrees can be the difference between a good and excellent espresso.

The Pump

Contrary to manual piston machines which use a lever to pressurize water, Rotary espresso machines uk machines rely on motorized pumps to deliver the nine atmospheric bars of pressure required to extract espresso. The pressure is created by removing tap water from a reservoir, and pumping it through a heat exchanger prior to it is shot through the ground coffee inside the group head.

Pumps are generally cheaper and last longer than piston-driven machines. However, both kinds of machines may degrade because of frequent use and insufficient cleaning. Pumps are also more complicated mechanically, which can increase the price of even the simpler models.

Some espresso machines use steam pressure instead of a pump for brewing espresso. The disadvantage of this is that the boiler that produces steam also raises the temperature of water until it reaches boiling which can cause excessive extraction. In addition these machines typically have to restore their pressure between cups, which takes time and energy.

Many commercial espresso machine machines make use of an rotary or vibrating pump, which is a vibration model using a rotating disc that generates the pressure and an rotary model that pushes hot water through the grounds at high speed. Both machines can make great espresso however rotary machines tend to be more quiet, durable and less likely to fail.

The dual boiler espresso machine

The boiler is the component that heats water to an optimal temperature for extraction. The resulting steam reaches the portafilter that contains the ground espresso coffee, and gets funnelled down into the cup. During this process, the steam causes pressure to push through the coffee grounds. This produces a layer of crema on top. This is one of the main characteristics of a great espresso.

There are three types of espresso machines, each with different pumps and brew temperature. There are a variety of ways in which the brew can be controlled, as well as the dimensions of the cup the machine can produce.

The first buy espresso makers machines were steam-based. The earliest espresso machines were steam types. The coffee tasted bitter and burned. This is why the Milanese manufacturers Luigi Bezzerra and Desiderio Pavoni created the modern espresso machine.

The most common espresso machine is a semiautomatic model with an electric pump. This is what people envision when they think of an best small espresso machine maker. If you have a semi-automatic machine you grind the beans and then tamp them by hand. However, the pump provides regulated water flow and pressure. This is a great compromise between the human touch and the mechanised accuracy.

The Filter

Espresso machines typically have a filter that separates the grounds of the coffee from the hot water. The filter is also an essential part of the machine's temperature control, since it helps to prevent overheating.

It also aids in flavor, as a filter lets you enjoy a longer bloom phase. This helps the beans to release their nuances and gives the chance for better extraction.

However, it is important to remember that even a high-quality filter can result in a poor cup of coffee, because the quality of the beans and extraction are important.

It's in this area that the magic happens. This is what makes espresso taste so delicious. The grouphead, sometimes referred to as the brew head, is where the portafilter (the thingy you put the ground coffee into) sits when you're making espresso.

In an espresso machine that is driven by steam, hot water is heated in an airtight container to create steam, which is then pushed through the grounds at high pressure. They are less expensive and easier for the user to maintain than pumps-driven models. They are however limited for creating the ideal conditions for brewing, as they operate with 1-1.5 bar of pressure. The perfect shot requires 9-10 bars.

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