How Does Machine Espresso Work?

The machine espresso utilizes precision pressure, and filtering technology that is amazing to make the coffee you enjoy. What exactly is it?

Espresso is produced by pushing hot water under pressure through finely-ground coffee. The process is similar to making drip coffee however the main difference lies in the pressure.

The Group Head

As the name suggests the group head is the place you place your portafilter while making espresso. It distributes water into the portafilter, and regulates the pressure of the extraction. There are several different types of group heads each with its distinct advantages and drawbacks. Some are focused on temperature stability, while others on pre-infusion capabilities, and still others are designed to control the lever. Some include a mix of features, such as the E61 one, which is to be the most popular among baristas because of its ability to offer multiple benefits in one package.

As you can see in the above photo the group head has a number of notches. You place your portafilter inside these notches, and then turn the head around to secure it. There is also a gasket made of rubber that is a part of the notches and helps to create a seal when you insert your portafilter into the machine. The notches on the head allow for a precise position of the portafilter which is necessary to ensure an efficient extraction.

Apart from allowing you effortlessly insert your portafilter the group head is responsible to ensure that the temperature remains even. This is achieved by cycling hot water around the portafilter and through the brew-basket to ensure that the temperature is constant for extraction. It is important to realize that even a slight deviation can make the difference between a decent and a great espresso.

The Pump

Motorized pumps in espresso machines that rotate provide the nine atmospheric bar pressure that is required to extract espresso. This differs from manually operated piston machines that employ levers. This pressure is built up by pumping water through a heat-exchanger and then through the ground coffee.

Pumps are typically less expensive than piston-driven machines, and tend to last longer, but both types of machine can be damaged by excessive use and electric Espresso Maker inadequate cleaning. Pumps are also more complex mechanically, which can raise the cost of even simple models.

Some espresso machines remove the pump completely and instead use steam pressure to brew espresso. The drawback is that the boiler that produces steam also increases the temperature of water to boiling which can cause excessive extraction. In addition these machines are often required to rebuild their pressure between cups, which requires time and energy.

A majority of espresso machines use the rotary or vibration pump, with a vibrating model using a rotating disc to create the pressure, and the rotary model pushing hot water through the grounds under high speed. Both machines produce great espresso, but rotary machines are quieter, more durable and less likely to break down.

The Boiler

The boiler is the one that is used to heat the water to the right temperature for extraction. The steam that is created gets to the portafilter which is a container for espresso grounds. It is then funneled into the cup. The steam generates enough pressure to push the grounds of the coffee through. This results in a layer crema that is then poured over. This is one of the hallmarks of a great espresso.

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

The first espresso machines were steam-types. The first espresso machines were steam-type machines. The coffee tasted bitter and burned. This is why the Milanese manufacturers Luigi Bezzerra and Desiderio Pavoni invented the modern espresso machine.

The most commonly used espresso maker is a semi-automatic device that has an electric pump. This is what people envision when they think of an espresso machines for home maker. With a semi-automatic machine you must grind the beans and then tamp them by hand. The pump is able to regulate the flow of water and pressure. This is an excellent compromise between human control and mechanised consistency.

The Filter

Typically, espresso machines have a filter to separate out the grounds of coffee when they pass through the hot water. The filter is also a vital part of the temperature control system as it keeps the machine from overheating.

It also improves flavor, since a filter lets you enjoy a longer bloom phase. This allows beans to let their nuances out and provides an opportunity for a better extraction.

It is important to remember that even the most efficient filter can result in a bad cup of coffee. The quality of the beans as well as the extraction, remain crucial.

It's here that the magic takes place. This is what makes espresso taste so good. The grouphead (also known as the brewhead) is where you place the portafilter, which is the thingy that you use to put the grounds of your coffee into when making espresso.

In an espresso machine that is driven by steam, 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 are typically cheaper and easier to maintain than pump-driven models. However, they are not as efficient in their ability to produce the ideal brewing conditions, as they only operate at 1-1.5 bars of pressure. However, the perfect shot requires 9-10 bar.

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 steam-driven Electric espresso Maker machines.