9 . What Your Parents Teach You About Machine Espresso

How Does machine espresso (http://Www.tianxiaputao.com/bbs/home.php?mod=space&uid=402698) Work?

Machine espresso utilizes precise pressure and amazing filter technology to make the coffee we love. But how exactly does it work?

To make an espresso hot water is forced under high pressure through finely ground coffee. The process is similar to making drip coffee but the difference is in the pressure.

The Head of the Group

The group head is the portafilter is inserted when you are making espresso. It disperses water in the portafilter, and then regulates the pressure of the extraction. There are a variety of group heads each with their own advantages and disadvantages. Some are focused on temperature stability, others on pre-infusion capabilities, and still others are designed to control the lever. Some are a combination, like the E61. This is a preferred choice for baristas because it offers multiple benefits in one package.

As you can see in the above photo the group head comes with several notches to place your portafilter before twisting it by hand to secure it. A rubber gasket is located inside the notches to help create a seal while you insert your portafilter. The notches allow for precise placement of the portafilter. This is crucial for an even extraction.

Aside from allowing you to easily connect your portafilter, the group head is also responsible for maintaining a consistent temperature. This is accomplished by cycling hot water around the portafilter and through the brew-basket, ensuring that the temperature is at the right level to extract the coffee. It is important to note that even a slight variation can mean the difference between a good and excellent espresso.

The Pump

Motorized pumps in rotary espresso machines supply the nine atmospheric bars of pressure required for espresso extraction. This is different from manually operated piston machines that employ levers. This pressure is generated by pumping water through a heat-exchanger and then through the ground coffee.

Pumps tend to be cheaper than piston-driven machines and tend to last longer, but both types of machines can be damaged by excessive use and inadequate cleaning. Pumps are also more complicated mechanically, and can add to the cost of even the simplest models.

Certain espresso machines utilize steam pressure instead of a pump for brewing espresso. The disadvantage of this is that the boiler that produces steam also raises the temperature of water until it reaches boiling which could lead to excessive extraction. These machines also have to constantly rebuild their pressure between cups. This requires energy and time.

Many espresso machines employ a vibration or rotary pump, with a vibrating model using a vibrating disc to create the pressure and a rotary model pushing hot water through the grounds under high speed. Both models can make a great espresso, but Rotary machines are quieter and more durable than vibration pumps.

The Boiler

The boiler is what will heat the water to the right temperature for extraction. The steam produced gets to the portafilter which holds the espresso grounds. It is then funneled into the cup. During this process, steam creates pressure to push through the grounds of the coffee. This results in a crema on the top of the espresso. This is one of the hallmarks of a good espresso.

There are three types of espresso machines, each with different types of pumps and the temperature of the brew. There are different ways in which the brew can be controlled, as well as the size of the cup that the machine can make.

The first espresso machines were steam-types. They employed one boiler to create both 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 burnt. The modern espresso machine was developed by the Milanese producers Luigi Bezzerra & Desiderio Pavoni.

The most popular espresso maker is a semiautomatic machine with an electric pump. When people think of espresso machines, they imagine these machines. Semi-automatic machines require you to grind and tamp the beans by yourself The pump, however, regulates the water flow and pressure. This is an excellent compromise between human touch and the mechanised consistency.

The Filter

Typically, espresso machines utilize a filter to separate out the coffee grounds as they pass through the hot water. The filter is also an important part of the temperature control system, as it prevents the machine from overheating.

A filter can also help with flavor, as it permits an extended flowering time. This helps the beans to release their flavors and provides an opportunity for a better extraction.

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

This is where the magic happens. It's what makes an espresso really taste good. The grouphead (also known as the brewhead) is where you put the portafilter, the thingy that you use to put the coffee grounds into, while making espresso machines for home.

Steam-driven espresso machines make use of hot water that is heated in an airtight container to make 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 ability to produce the ideal conditions for brewing because they operate at 1-1.5 bars of pressure. The perfect shot requires 9 bar espresso machine-10 bar.

In recent years, espresso machines driven by a compressed air pump have become increasingly popular. They use an air-compressor to force hot water into the ground and are more mobile than steam-driven electric espresso machines.