9 Lessons Your Parents Taught You About Machine Espresso

How Does Machine Espresso Work?

Machine espresso employs precise pressure and incredible filter technology to produce the coffee we love. 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 main difference.

The Group Head

As the name suggests the group head is the place you place your portafilter when making espresso. It is responsible for dispersing water into the portafilter and controlling the pressure of the resulting extraction. There are a variety of group heads each with their own advantages and disadvantages. Some are specifically designed for stability in temperature, while others are designed to handle pre-infusion. Others are made to control the lever. Some contain a variety of features, such as the E61 one, which is to be the most popular among baristas for its ability to offer multiple benefits in one package.

As you can see from the picture above the group head is equipped with several notches. You place your portafilter in these notches, then twist the head to secure it. A gasket of rubber is situated in the notches to create a seal when you insert your portafilter. The notches permit precise placement of your portafilter. This is essential for an even extraction.

Apart from allowing you effortlessly insert your portafilter the group head is also responsible for maintaining an even temperature. It does this by circulating hot water through the brew pan and around the portafilter, ensuring that it is always at the right temperature to extract. This is important because even a small difference in temperature can make the difference between good and great espresso.

The Pump

In contrast to manual piston machines that use a lever to pressurize water, rotating espresso machines rely upon motorized pumps to provide the nine atmospheric bars of pressure necessary to extract espresso. The pressure builds by removing tap water from a reservoir, and pumping it through a heat exchanger prior to being pushed through the ground coffee in the group head.

Pumps are generally more affordable and last longer than piston-driven machines. However, both types of machines can degrade because of frequent use and poor cleaning. Pumps are also more complicated mechanically, which could increase the cost of even the most basic models.

Certain espresso machines remove the pump completely and utilize steam pressure to make espresso. This could lead to over-extraction since the boiler that makes steam also warms the water to boil. The machines must also constantly rebuild their pressure in between cups. This requires energy and time.

Many espresso machines utilize an rotary or vibrating pump, with a vibrating model using a vibrating disc to create the pressure, and the rotary model pushing hot water through the grounds at high speed. Both machines produce great espresso, but rotary machines are quieter, more durable and less likely to break.

The Boiler

The boiler is the one that is used to heat the water to a temperature that is ideal for extraction. The steam created gets to the portafilter which contains the espresso coffee grounds. The steam is then channeled into the cup. During this process, steam causes pressure to push through the coffee grounds. This creates a crema on the top of the espresso. This is one of the main characteristics of a great espresso machine sale.

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

The first espresso machines were steam-types. They employed only one boiler to make both steam and brew, but the pressure they could generate was low - only two bars of atmospheric pressure at most. The coffee tasted bitter and burned. This is why the Milanese producers Luigi Bezzerra and Desiderio Pavoni created the modern espresso machine.

The most commonly used espresso machine is a semiautomatic with an electric pump. When people think of espresso machines, they think of these machines. With a semi-automatic machine, you need to grind the beans and then tamp them yourself but the pump controls the flow of water and pressure. This is a fantastic compromise between human control and mechanised consistency.

The Filter

Espresso machines usually have filters that separate the grounds of the coffee from the hot water. The filter is also a vital component of the machine's temperature control, as it prevents overheating.

A filter also helps with flavor, Machine Espresso as it permits a longer flowering phase. This allows the beans to release their flavor and allows for a better extraction.

It is important to keep in mind that even the finest filter could result in a poor cup of coffee. The quality of the beans, and the extraction process remain vital.

It's here that the magic happens. This is what makes espresso taste so delicious. The grouphead, often called the brew head, is where the portafilter (the thing you put the coffee grounds into) is placed when you're making best espresso machine.

In the steam-driven espresso machine hot water is heated in an airtight tank to create steam. Steam then pushes the hot water through the grounds at a high pressure. These kinds of machines are usually less expensive and simpler to maintain than pump-driven models. They are however limited to create the perfect conditions for brewing since 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 become more popular. They use an air compressor to push the hot water through the grounds and are more portable than electric steam-driven machines.