How Does Machine Espresso Work?

Machine pro espresso machine utilizes precise pressure and mind-blowing filter technology to make the coffee we love. What exactly is it?

To make espresso hot water is forced under high pressure through finely ground coffee. The process is similar to that of making drip coffee. However it is the pressure that makes the main difference.

The Head of the Group

As the name implies, the group head is the place you place your portafilter when making espresso. It disperses water in the portafilter, and then regulates the pressure during the extraction. There are a variety of group heads each with distinct advantages and disadvantages. Some are focused on temperature stability, others on pre-infusion capabilities, while others are designed to control the lever. There are even some that have a combination of features, such as the E61 that is to be the most popular among baristas due to its capacity to provide multiple benefits in one package.

As you can see from the picture above the head of the group is fitted with several notches. The portafilter is placed in these notches, then twist the head to secure it. A gasket made of rubber is placed within the notches to create a seal as you insert your portafilter. The notches permit precise placement of the portafilter. This is essential for a consistent extraction.

The group head is not just able to allow the portafilter to be inserted easily however, it also keeps an even temperature. This is done by cycling hot water around the portafilter, and through the brew-basket, making sure that the temperature is at the right level to extract the coffee. It is important to remember that even a few degree variation can mean the difference between a great and a excellent espresso.

The Pump

Unlike manual piston machines, which rely on a lever that pressurize water, the rotary best espresso machine uk machines use motorized pumps to deliver the nine atmospheric bars of pressure required for espresso extraction. This pressure builds up by drawing tap water from a reservoir, and cafe Espresso machine pumping it through a heat exchanger prior to being pumped 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 may degrade because of frequent use and insufficient cleaning. Pumps are also more complicated mechanically, and can add to the cost of even the most basic models.

Certain espresso machines do away with the pump completely and employ steam pressure to create italian espresso machines. The downside is that the boiler that produces steam also increases the temperature of the water until it reaches boiling which can cause over-extraction. These machines also have to continuously rebuild their pressure between cups. This requires energy and time.

Many espresso machines make use of either a vibration or rotary pump. A vibration model uses an oscillating disk to create pressure, whereas a Rotary model pushes hot coffee through the ground at high speed. Both types of machine can produce an excellent espresso, however Rotary machines are quieter and more durable than vibration pumps.

The Boiler

The boiler is the one that heats the water to the perfect temperature to extract. The resultant steam then reaches the portafilter which holds the ground espresso coffee and is then pumped into the cup. In this process, the steam creates pressure to push through the coffee grounds. This results in a layer of crema on top. This is one of the hallmarks of a good espresso.

There are three kinds of espresso machines, each having distinct pumps and the temperature of the brew. There are various ways to control the brew as well as the size of cup that can be produced by the machine.

The first espresso machines were steam-types. They used one boiler to create steam and brew, but the pressure they could generate was low - only two bars of atmospheric pressure maximum. The coffee tasted bitter and burnt. This is the reason Milanese makers Luigi Bezzerra and Desiderio Pavoni developed the modern espresso machine.

The most commonly used espresso maker is a semi-automatic device that has an electric pump. These are the images people have when they think of an Cafe Espresso Machine maker. Semi-automatic machines require you to grind and tamp the beans on your own, but the pump regulates the water flow and pressure. This is a great compromise between the human touch and the mechanised consistency.

The Filter

Espresso machines usually have filters that separate the grounds of coffee from hot water. The filter is also a vital part of the machine's temperature control, since it helps to prevent overheating.

It also enhances flavor, since a filter lets you enjoy a longer bloom time. This helps the beans to let their nuances out and provides an opportunity for better extraction.

However it is crucial to keep in mind that even a top filter could result in a bad cup of coffee as the quality of the beans and extraction is vital.

It's here that the magic takes place. This is the reason why espresso tastes so delicious. The grouphead (also called the brewhead) is where you place the portafilter - the thingy that you put the coffee grounds in, while making espresso.

In an best espresso machine machine that is driven by steam, hot water is heated in an airtight tank to create steam. This is then pushed through the grounds with high pressure. These machines are less expensive and are easier for the user to maintain than pumps-driven models. However, they are limited in their capacity to create the perfect conditions for brewing, since they are only operating at 1-1.5 bars of pressure. However, the perfect shot requires 9-10 bar.

In recent years, cafe Espresso machine compressed-air-pump-driven espresso machines have become more popular. They utilize an air compressor to push hot water through the ground and are much more mobile than steam-driven electric espresso machines.