10 Things That Your Family Teach You About Machine Espresso

How Does machine Espresso (http://Kwba.or.kr/bbs/board.php?bo_table=menu0406&wr_id=246814) Work?

Machine espresso employs precise pressure and mind-blowing filter technology to create the coffee we love. But how exactly does it work?

Espresso is created by forcing hot water under high pressure through finely ground coffee. The process is similar to making drip coffee. However, it is the pressure that makes the main difference.

The Head of the Group

The group head is the portafilter you put in when making espresso. It is responsible for dispersing the water into the portafilter before controlling the pressure of the extraction. There are various kinds of group head each with its unique advantages and disadvantages. Some are designed to provide temperature stability while others are specifically designed to handle pre-infusion. Others are built to control the lever. Some come with a combination of both, like the E61. This is a very popular choice for baristas due to the fact that it has multiple advantages in a single package.

As you can see in the photo above the group head is equipped with several notches. The portafilter is placed inside these notches, and then twist the head to secure it. A gasket of rubber is situated inside the notches to help create a seal as you insert your portafilter. The notches on the head permit an exact placement of the portafilter, which is crucial to ensure an efficient extraction.

In addition to allowing you effortlessly insert 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-basket, making sure that the temperature is constant for extraction. It is crucial to keep in mind that even a few degree variation can mean the difference between a good and excellent espresso.

The Pump

In contrast to piston machines that are manually operated, which rely on a lever to pressurize water, the rotary espresso machines use motorized pumps to supply the nine atmospheric bars of pressure that are required for espresso extraction. The pressure builds by drawing tap water from a reservoir and pumping it through a heat exchanger prior being pumped through the ground coffee in the group head.

Pumps tend to be less expensive and last longer than piston-driven machines. However, both types of machines are susceptible to degrading due to overuse and poor cleaning. Pumps are also more complicated mechanically, which can raise the cost of even the simpler models.

Some espresso machines make use of steam pressure instead of a pump for brewing espresso. This could lead to over-extraction since the boiler that makes steam also heats the water until it comes to a boil. These machines also have to continuously rebuild their pressure between cups. This requires energy and time.

Many buy espresso machine machines employ either a rotary or vibration pump, with a vibrating model using a vibrating disc to create the pressure, and an rotary model that pushes hot water through the grounds at high speed. Both models can make excellent espresso, but Rotary machines are quieter and more durable than vibration pumps.

The Boiler

The boiler is the one that makes the water warm to a temperature that is ideal for extraction. The resultant steam then reaches the portafilter that contains the ground espresso coffee, and gets funnelled down into the cup. During this process the steam creates enough pressure to push the grounds of the coffee through. This results in a layer of 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 a different type of pump and the temperature of the brew. There are a variety of ways that the brew can be controlled as well as the dimensions of the cup the machine can produce.

The first espresso machines were steam types. They employed one boiler to create steam and brew, however the pressure they were able to create was minimal - two bars of atmospheric pressure, at most. The coffee tasted bitter and burnt. The modern espresso machine was designed by the Milanese manufacturers Luigi Bezzerra & Desiderio Pavoni.

The most common espresso maker is a semi-automatic one that has an electric pump. When people think of espresso machines, they picture these machines. Semi-automatic espresso machine machines require you to grind and tamp your beans yourself, but the pump regulates the flow of water and pressure. This is a fantastic compromise between human control and mechanized consistency.

The Filter

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

A filter also improves flavor since it allows for the beans to flower for a longer period of time. This allows beans to release their nuances and gives an opportunity to improve extraction.

It is important to keep in mind that even the best cheap espresso machine filter can result in a bad cup of coffee. The quality of the beans as well as the extraction, are still very important.

It's in this area that the magic occurs. This is what makes espresso taste so delicious. The grouphead (also known as the brewhead) is where you put the portafilter, which is the thingy which you put the coffee machine espresso grounds into, while making espresso.

Steam-driven espresso machines use hot water that is heated in an airtight container to produce steam. The steam then pushes hot water through coffee grounds under high pressure. These machines are cheaper and easier for the user to maintain than pumps-driven models. However, they are not as efficient in their capacity to create the perfect conditions for brewing, since they are only operating at 1-1.5 bars of pressure. However, the perfect shot requires 9-10 bars.

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