3 Common Reasons Why Your Machine Espresso Isn't Performing (And What …

How Does Machine Espresso Work?

The machine espresso uses precision pressure, and a filter technology that is awe-inspiring to create the coffee you love. What exactly is it that makes it work?

Espresso is created by forcing hot water under pressure through finely-ground coffee. The process is similar to making drip coffee, but the key difference is in the pressure.

The Group Head

The group head is the portafilter that is inserted when you are making espresso. It is responsible for dispersing water into the portafilter and controlling the pressure that results from the extraction. There are a variety of types of group heads, each with their unique advantages and drawbacks. Some are designed for stability of temperature while others are designed to handle pre-infusion. Others are built to control the lever. There are some that have a combination of features, like the E61, which is considered the classic choice among many baristas due to its capacity to offer multiple perks in one package.

As you can see in the image above the group head comes with several notches where you place your portafilter before twisting it manually to secure it. A rubber gasket is located inside the notches, which helps create a seal when you insert your portafilter. The notches on the head permit an exact position of the portafilter which is vital for an even extraction.

In addition to allowing you easily insert your portafilter, the group head is also responsible to ensure that the temperature remains even. This is achieved by cycling hot water around the portafilter and through the brew-basket, ensuring that the temperature is at the right level for extraction. This is vital, because even a few degrees can be the difference between a good and great espresso.

The Pump

In contrast to piston machines that are manually operated, which rely on a lever that pressurize water, Rotary espresso machines rely on motorized pumps to provide the nine atmospheric bars of pressure required for espresso extraction. The pressure is built by pumping water through a heat exchanger and then through the ground coffee.

Pumps tend to be cheaper than piston-driven machines, and tend to last longer, although both types of machines can become damaged due to excessive use and poor cleaning. Pumps are also more complex mechanically, which could increase the cost of even the simplest models.

Some espresso machines remove the pump entirely and employ steam pressure to create espresso. The disadvantage of this is that the boiler that produces steam also increases the temperature of the water until it reaches boiling and can result in excessive extraction. They also have to continuously rebuild their pressure between cups. This takes energy and time.

Many espresso machines use an rotary or a vibration pump. A vibration model utilizes a rotating disk to generate pressure, whereas a Rotary model pushes hot coffee through the ground at a rapid speed. Both machines can make excellent espresso however rotary machines tend to be more quiet, durable and less likely to break.

The Boiler

The boiler is the one that makes the water warm to a temperature that is ideal to extract. The resulting steam is then transferred to the portafilter containing ground espresso beans and is then pumped down into the cup. During this process the steam generates enough pressure to push the coffee grounds through. This results in a crema on top of the espresso. This is a hallmark of a good espresso.

There are three kinds of espresso machines, each having different types of pumps and brew temperature. There are also different ways that the brew may be controlled, as well as the size of the cup that the maker can create.

The earliest espresso machines were steam-based. The first espresso machines were steam-type machines. This resulted in the coffee tasting bitter and burnt. This is the reason Milanese manufacturers Luigi Bezzerra and Desiderio Pavoni invented the modern espresso machine.

The most commonly used espresso maker is a semi-automatic one that has an electric pump. When people think of espresso machines, they picture these machines. Semi-automatic machines espresso machines require you to grind and tamp the beans yourself however the pump controls the water flow and pressure. This is a perfect compromise between human control and mechanised accuracy.

The Filter

Espresso machines usually use a filter that separates the coffee grounds from the hot water. The filter is also an essential part of the machine's temperature control, since it stops overheating.

Filters also aid in flavor, as it permits the beans to flower for a longer period of time. This lets the beans release their flavors, and also allows for better extraction.

It is important to keep in mind that even the most efficient filter could result in a poor cup of coffee. The quality of the beans and the extraction, are still crucial.

It's here that the magic occurs. 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 use to put the grounds of coffee into when making espresso.

Steam-driven espresso machines make use of hot water that is heated inside an airtight container to create steam. The steam then pushes hot water into the grounds of coffee at high End Espresso machine pressure. They are less expensive and easier for the user to maintain than pumps-driven models. However, they are limited in their capacity to create the ideal brewing conditions, because they operate at 1-1.5 bars of pressure. While the perfect shot requires 9 bar espresso machine-10 bar.

In recent years, High End Espresso Machine compressed air pump-driven espresso machines espresso machines have been gaining popularity. They utilize an air compressor to push hot water into the grounds and are much more portable than electric steam-driven machines.