10 Machine Espresso Meetups You Should Attend
How Does Machine Espresso Work?
The machine espresso uses precise pressure and filter technology that is mind-blowing to make the coffee you love. How exactly does it work?
Espresso is created by forcing hot water at high pressure through finely ground coffee. The process is similar to making drip coffee but the key difference is in the pressure.
The Group Head
As the name suggests the group head is where you insert your portafilter when making espresso. It disperses water in the portafilter and regulates the pressure during the extraction. There are many different types of group heads each with their own advantages and disadvantages. Some are specifically designed for stability of temperature while others are built to handle pre-infusion. Others are made to control the lever. Some include a mix of features, such as the E61 that is the most popular choice among baristas for its ability to provide multiple benefits in one package.
As you can see in the above photo the head of the group is fitted with a variety of notches. It is possible to place your portafilter inside these notches, and then turn the head around to secure it. There is also a rubber gasket in the notches, which helps create an airtight seal when you insert your portafilter into the machine. The notches on the head permit an exact placement of the portafilter, which is necessary for a consistent extraction.
Aside from allowing you to easily insert your portafilter, the group head is responsible for maintaining an even temperature. This is done by cycling hot water around the portafilter and through the brew basin, ensuring that the temperature is always at the right level for extraction. This is important, as even a few degrees can make the difference between a good and great espresso.
The Pump
Motorized pumps in rotary espresso machines provide the nine atmospheric bar pressure required for espresso extraction. 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 generally less expensive and last for longer than piston-driven machines. However, both types of machines can degrade due to overuse and inadequate cleaning. Pumps are also more complicated mechanically, which could increase prices of even simple models.
Certain espresso machines utilize steam pressure instead of a pump in order to brew professional espresso machine for home, click this site,. The drawback of this is that the same boiler that produces steam also increases the temperature of water to the point of boiling which can cause over-extraction. The machines also need to continuously rebuild their pressure between cups. This takes energy and time.
A large majority of espresso machines employ a rotary or vibration pump. A vibration model makes use of an oscillating disk to create pressure, whereas the rotating model pushes hot water through the ground at a high speed. Both machines can make great espresso, however rotary machines are more stable, quieter and less likely to fail.
The Boiler
The boiler is what makes the water warm to a temperature that is ideal for extraction. The steam produced reaches the portafilter, which contains the espresso coffee grounds. It is then funneled into the cup. During this process, steam causes pressure to push through the grounds of the coffee. This creates a layer crema that is then poured over. This is a sign of a great espresso.
There are three different types of espresso machines, each with different pumps and the temperature of the brew. There are various ways to control the strength of the brew and the size of the cup that can be made by the machine.
The first espresso machines were steam-types. The first espresso machines were steam-type machines. The coffee tasted bitter and burned. The modern espresso machine was designed by the Milanese makers Luigi Bezzerra & Desiderio Pavoni.
The most popular espresso machine is a semiautomatic model with an electric pump. These are the images people have when they think of an espresso machine. With a semi-automatic machine, you need to grind the beans and then tamp them by hand. The pump regulates the flow of water and pressure. This is a great compromise between the human touch and the mechanized quality.
The Filter
Typically, espresso machines employ filters that separate the grounds of coffee as they move through 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 allows for the beans to flower for a longer period of 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 can make a bad cup of coffee. The quality of the beans, and the extraction process, remain crucial.
It's in this area that the magic occurs. This is the reason why espresso tastes so good. The grouphead (also known as the brewhead) is where you place the portafilter, the device used to place the grounds of coffee into when making espresso.
In a steam-driven espresso coffee machine for home machine hot water is heated in an airtight container to produce steam, which then pushes the hot water through the grounds under high pressure. These types of machines are generally less expensive and easier to maintain than pump-driven models. However, they are limited in their capacity to create the ideal conditions for brewing as they only operate at 1-1.5 bars 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 the hot water through the grounds and are significantly more portable than electric steam-driven machines.