5 Killer Quora Questions On Machine Espresso

How Does Machine Espresso Work?

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

To make espresso hot water is pushed under pressure through finely ground coffee. The process is similar to making drip coffee and espresso machine. However it is the pressure that makes the main difference.

The Head of the Group

The group head is the portafilter that you put in when making retro espresso machine. It disperses water into the portafilter, and then regulates the pressure during the extraction. There are several different types of group heads, each with their unique advantages and drawbacks. Some are specifically designed for the stability of temperature while some are specifically designed to handle pre-infusion. Others are made to control the lever. Some come with a combination of both, like the E61. This is a popular choice among baristas since it provides multiple benefits in one package.

As you can see in the picture above, the group head is fitted with a variety of notches. The portafilter is placed in these notches and then twist the head to secure it. A gasket of rubber is situated in the notches to make a seal when you insert your portafilter. The notches on the head allow for an exact position of the portafilter which is vital for an even extraction.

The group head not only lets you to put in your portafilter easily however it also keeps a constant temperature. This is done by cycling hot water around the portafilter, and through the brew basin, ensuring the temperature is always right for extraction. It is important to realize that even a few degree difference can make the difference between a good and excellent espresso.

The Pump

The motorized pumps used in espresso machines that rotate provide the nine atmospheric bars of pressure required for travel espresso Maker extraction. This differs from manually operated piston machines that employ a lever. This pressure is generated by pumping water through a heat-exchanger and then through the ground coffee.

Pumps tend to be less expensive and last longer than piston-driven machines. However, both kinds of machines can deteriorate due to overuse and inadequate cleaning. They also create mechanical complexity and can lead to an expensive price for even the most basic models.

Certain espresso machines remove the pump completely and instead use steam pressure to brew espresso. This can lead to over-extraction as the boiler that produces steam also heats the water to boil. In addition these machines are often required to restore their pressure between cups, which requires time and energy.

A large majority of espresso machines employ a rotary or vibration pump. A vibration model makes use of the vibrating disk to create pressure, whereas the Rotary model pushes hot coffee through the ground at a rapid speed. Both machines produce great espresso however rotary machines tend to be more stable, quieter and less likely to break.

The Boiler

The boiler is the component which heats the water to the ideal temperature to extract. The steam that is created is then directed to the portafilter, which holds the espresso grounds. It is then poured into the cup. During this process the steam causes enough pressure to push the coffee grounds through. This creates a crema on top of the espresso. This is a hallmark of a good espresso.

There are three types of espresso makers, and they differ in the type of pump they employ and the degree of heat that the brew is. There are various ways to control the amount of brew, as well as the size of cup that can be made by the machine.

The first espresso machines were steam-based. They employed one boiler to create steam and brew, however, the pressure they could produce was not very high - two bars of atmospheric pressure at most. The coffee tasted bitter and burned. The modern espresso machine was developed by the Milanese producers Luigi Bezzerra & Desiderio Pavoni.

The most well-known espresso maker is a semiautomatic machine that has an electric pump. This is what people envision when they think of an espresso machine. With a semi-automatic machine you grind the beans and then tamp them yourself but the pump controls the flow of water and pressure. This is a great compromise between human control and mechanized consistency.

The Filter

Espresso machines typically use filters that separate the grounds of the coffee from the hot water. The filter is also a vital part of the machine's temperature control, since it stops overheating.

Filters also aid in flavor, as it permits a longer flowering phase. This allows the beans to release their flavors, and allows for a better extraction.

It is important to remember that even the most efficient filter can make a bad cup of coffee. The quality of the beans and the extraction process are still very important.

It's in this area that the magic happens. This is what makes espresso taste so delicious. The grouphead, often called the brew head, is where the portafilter (the thingy you put the ground coffee in) is placed when making espresso.

Steam-driven espresso machines use hot water that is heated inside an airtight container to make steam. The steam then moves hot water through the coffee grounds under high pressure. These kinds of machines tend to be less expensive and easier to maintain than pumps-driven models. They are however limited in their ability to create the ideal conditions for brewing since 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 use an air compressor to push hot water through grounds and are more portable than steam-driven electric machines.