10 Quick Tips About Machine Espresso

How Does Machine Espresso Work?

The machine espresso makes use of precision pressure, and a filter technology that is mind-blowing to make the coffee you love. But how exactly does it work?

To make an espresso machine with grinder hot water is pushed under pressure through finely ground coffee. The process is similar to making drip coffee, but the difference is in the pressure.

The Head of the Group

As the name suggests, the group head is where you put your portafilter in when brewing espresso. It is responsible for dispersing the water into the portafilter and then controlling the pressure that results from the extraction. There are several different types of group heads, each with their own advantages and disadvantages. Some are designed to provide stability of temperature while others are built to handle pre-infusion. Others are built to control the lever. There are some that contain a variety of features, such as the E61, which is considered to be the most popular among baristas because of its ability to offer multiple perks in a single package.

As you can see in the above photo the head of the group is fitted with several notches. It is possible to place your portafilter into these notches and turn the head around to secure it. There is also a gasket made of rubber that is a part of the notches and helps create the seal when you insert your portafilter into the machine. The notches on the head allow for an exact location of the portafilter which is necessary to ensure an even extraction.

Aside from allowing you to easily connect your portafilter, the group head is responsible for maintaining an even temperature. This is achieved by cycling hot water around the portafilter and through the brew basin, ensuring the temperature is always right for extraction. It is important to remember that even a small deviation can make the difference between a great and a excellent espresso machines home.

The Pump

The motorized pumps that are used in rotary espresso machines provide the nine atmospheric bar pressure needed to extract espresso. This differs from manual piston machines that rely on levers. This pressure builds up by removing tap water from a reservoir, and pumping it through a heat exchanger prior to being shot through the ground coffee and espresso maker inside the group head.

Pumps tend to be less expensive and last longer than piston-driven machines. However, both types of machines can degrade due to overuse and insufficient cleaning. They also create mechanical complexity which can result in an expensive price for even the most basic models.

Some espresso machines do away with the pump completely and instead make use of steam pressure to make espresso. The drawback of this is that the same boiler that produces steam also raises the temperature of the water to the point of boiling and can result in excessive extraction. The machines also need to continuously rebuild their pressure between cups. This requires energy and time.

Many espresso machines use an rotary or a vibration pump. A vibration model utilizes an oscillating disk to create pressure, whereas a rotating model pushes hot water through the ground at high speed. Both machines can make great espresso however rotary machines tend to be more quiet, durable and less likely to fail.

The Boiler

The boiler makes the water warm to the right temperature for extraction. The resulting steam is then transferred to the portafilter that contains the ground espresso and is then funneled down into the cup. The steam is able to create enough pressure to push the coffee grounds through. This results in a whipped-up the top espresso machines of the espresso. This is the hallmark of a good espresso.

There are three types of espresso makers, and they differ in the type of pump they use and the degree of heat that the brew is. There are a variety of ways that the brew can be controlled, as well as the dimensions of the cup the machine can make.

The first espresso machines were steam-type. They utilized only one boiler to make both steam and brew however, the pressure they could produce was very low - just two bars of atmospheric pressure at most. This resulted in the coffee tasting burnt and bitter. This is the reason why Milanese makers 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 envision these machines. With a semi-automatic machine you need to grind the beans and tamp them by hand. The pump regulates the flow of water and pressure. This is a perfect compromise between human control and mechanised consistency.

The Filter

Espresso machines usually use filters that separate the grounds of the coffee from hot water. The filter is also an important component of the temperature control system as it keeps the machine from overheating.

A filter also improves flavor because it allows for an extended flowering time. This allows the beans to release their nuances, and allows for a 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 as well as the extraction, are still very important.

This is where the magic happens, and it's what makes an espresso really taste great. The grouphead (also called the brewhead) is where you put the portafilter, the device used to place the coffee grounds in, when making espresso.

In a steam-driven Espresso Machines Uk machine hot water is heated in an airtight tank to create steam. Steam is then pushed through the grounds at a high pressure. These kinds of machines tend to be less expensive and simpler to maintain than pumps-driven models. They are however limited in their ability for creating the ideal conditions for brewing as they only operate with 1-1.5 bar of pressure. The perfect shot requires 9-10 bars.

In recent times, espresso machines powered by compressed air-pump have become increasingly popular. They utilize an air compressor to push hot water into the grounds and are more portable than electric steam-driven machines.