3 Reasons You're Not Getting Machine Espresso Isn't Working (And What You Can Do To Fix It)

How Does Machine Espresso Work?

best cheap espresso machine utilizes precise pressure and filtering technology that is amazing to create the coffee you love. What exactly does it work?

To make espresso hot water is pushed under pressure through finely ground coffee. The process is similar to that of making drip coffee. However the pressure is the major difference.

The Head of the Group

As the name implies the group head is the place you insert your portafilter when brewing espresso. It distributes water into the portafilter, and then regulates the pressure of the extraction. There are several different types of group head, each with their unique advantages and drawbacks. Some are focused on temperature stability, some on pre-infusion capabilities, while others are designed to control the lever. Some have a combination, such as the E61. This is a very popular choice for baristas because it offers 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 before twisting it with your hands to secure it. There is also a gasket of rubber that resides inside the notches to help create the seal when you insert your portafilter into the machine. The notches on the head permit an exact location of the portafilter which is vital for a consistent extraction.

The group head not only allows you to put in your portafilter easily, but it also maintains the same temperature. This is done by cycling hot water around the portafilter, and through the brew-basket to ensure that the temperature is constant for extraction. This is important, as even a few degrees can make the difference between a good and excellent espresso.

The Pump

The motorized pumps that are used in espresso machines rotary provide nine atmospheric bars of pressure required for espresso extraction. This differs from manual piston machines which 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 inside the group head.

Pumps tend to be cheaper than piston-driven machines and tend to last longer, however both types of machines could be damaged by excessive use and inadequate cleaning. Pumps are also more complicated mechanically, which could increase prices of even simpler models.

Some espresso machines make use of steam pressure instead of a pump for brewing espresso. This can cause over-extraction because the boiler that produces steam also heats the water to boil. In addition these machines typically have to restore their pressure between cups, which takes time and energy.

Many espresso machines utilize a vibration or rotary pump, which is a vibration model using a vibrating disc that generates the pressure and the rotary model pushing hot water through the grounds under high speed. Both models are capable of producing excellent espresso, however the rotary models are quieter and more durable than vibration pumps.

The Boiler

The boiler is what heats the water to the right temperature to extract. The resulting steam is then transferred to the portafilter containing ground espresso beans and is then pumped into the cup. During this process, steam creates pressure that pushes 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 kinds of espresso makers. They differ in the type of pump they employ and how hot the brew is. There are various ways that the brew may be controlled as well as the dimensions of the cup the maker can create.

The first espresso machines were steam-based. They used a single boiler to make both steam and brew, however, the pressure they could produce was very low - just two bars of atmospheric pressure, at most. The coffee tasted bitter and burnt. The modern espresso machine was designed by the Milanese makers Luigi Bezzerra & Desiderio Pavoni.

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

The Filter

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

It also helps with flavor, as a filter allows for a more prolonged bloom phase. This allows the beans to release their nuances, and allows for better extraction.

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

This is where the magic happens, and it's what makes an espresso really taste good. The grouphead, sometimes referred to as the brewhead, is where the portafilter (the thingy you put the coffee grounds into) is placed when making espresso.

In a steam-driven espresso machine hot water is heated in an airtight container to create steam, which then pushes the hot water through the grounds at high pressure. These kinds of machines tend to be less expensive and simpler to maintain than pumps-driven models. However, they are limited in their ability to produce the ideal brewing conditions, since they are only operating at 1-1.5 bars of pressure. The perfect shot requires 9-10 bar.

In recent times, espresso machines powered by compressed air-pump are becoming increasingly popular. They use an air compressor to force hot water into the ground and are more mobile than electric steam-driven espresso machines.