12 Statistics About Machine Espresso To Bring You Up To Speed The Cooler. Cooler
How Does Machine Espresso Work?
Machine espresso makes use of precise pressure and mind-blowing filter technology to make the coffee we love. How exactly does it work?
Espresso is made by forcing hot water under high pressure through finely ground coffee. The process is similar to making drip coffee, but the major difference is in the pressure.
The Group Head
The group head is the portafilter that you put in when making espresso. It is responsible for dispersing water into the portafilter, and controlling the pressure of the resulting extraction. There are espresso makers of group heads each with distinct advantages and drawbacks. Some focus on temperature stability, whereas others on pre-infusion options, and others are designed to control the lever. There are some that come with a range of features, like the E61, which is considered the most popular choice among baristas due to its capacity to offer multiple perks in one package.
As you can see in the image above, the group head has a number of notches. The portafilter is placed in these notches and then twist the head to lock it. A gasket made of rubber is placed within the notches to make a seal when you insert your portafilter. The notches allow for an exact placement of the portafilter. This is vital for a consistent extraction.
Aside from allowing you to effortlessly insert your portafilter the group head is also responsible for maintaining a consistent temperature. It does this by cycling hot water through the brew container and around the portafilter to ensure that it is always at the correct temperature to extract. This is important because even a small difference in temperature can mean the difference between excellent and great espresso.
The Pump
The motorized pumps used in espresso machines rotary provide nine atmospheric bar pressure that is required to extract espresso. This is different from manual piston machines that use levers. This pressure is built up by pumping water through a heat-exchanger and then through the ground coffee.
Pumps tend to be less expensive than piston-driven models, and they tend to last longer, but both types of machines may get damaged through overuse and lack of cleaning. Pumps are also more complex mechanically, which could increase prices of even simple models.
Some espresso machines employ steam pressure instead of a pump to brew espresso. This can lead to over-extraction as the boiler that makes steam also heats the water to boil. In addition the machines often have to rebuild their pressure between cups, which requires time and energy.
Many espresso machines use an rotary or a vibration pump. A vibration model utilizes the vibrating disk to create pressure, whereas the Rotary model pushes hot coffee through the ground at high speed. Both models can produce an excellent espresso, however Rotary machines are quieter and more durable than vibration pumps.
The Boiler
The boiler is what heats the water to a temperature that is ideal to extract. The steam created reaches the portafilter, which contains the espresso coffee grounds. It is then poured into the cup. During this process, the steam creates pressure to push through the coffee grounds. This results in a layer of crema that is then poured over. This is one of the hallmarks of a good espresso.
There are three types of espresso machines, each having distinct pumps and the temperature of the brew. There are a variety of ways that the brew can be controlled, as well as the size of the cup that the machine is capable of making.
The first espresso machines were steam type. The first espresso machines were steam types. This led to the coffee tasting burnt and bitter. The modern espresso machine was invented by the Milanese makers Luigi Bezzerra & Desiderio Pavoni.
The most well-known espresso machine is a semiautomatic model with an electric pump. These are the things people think of when they imagine an espresso machine. Semi-automatic machines require you to grind and tamp the beans yourself while the pump controls the flow of water and pressure. This is a great compromise between the human touch and the mechanised consistency.
The Filter
Espresso machines usually use a filter that separates the coffee grounds from the hot water. The filter is also a crucial element of the temperature control system, as it keeps the machine from overheating.
It also helps with flavor, as it allows for a more prolonged bloom phase. This allows the beans to let their nuances out, and also allows for better extraction.
However it is crucial to remember that even a good filter can result in a poor cup of coffee, since the quality of the beans and extraction is still vital.
This is where the magic happens, and it's what makes espresso taste great. The grouphead (also known as the brewhead) is where you put the portafilter, the thingy used to place the grounds of coffee into when making espresso.
Steam-driven espresso machines use hot water heated in an airtight container to make steam. The steam then moves hot water through the grounds of coffee at high pressure. These machines are less expensive and easier to maintain than pumps-driven models. However, they are not as efficient in their ability to produce the perfect conditions for brewing, because they operate at 1-1.5 bars of pressure. The perfect shot requires 9-10 bars.
In recent years, espresso machines powered by a compressed air pump have become increasingly popular. They utilize an air compressor to push hot water through the grounds, and are far more portable than electric steam-driven machines.