20 Trailblazers Leading The Way In Machine Espresso

How Does Machine Espresso Work?

The machine espresso makes use of precision pressure, and filtering system that is awe-inspiring to create the coffee you enjoy. What exactly does it work?

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

The Head of the Group

As the name suggests, the group head is the place you put your portafilter in when making professional espresso machine for home (click here!). It is responsible for dispersing water into the portafilter before controlling the pressure of the resulting extraction. There are a variety of group heads each with their own advantages and drawbacks. Some are specifically designed for temperature stability while others are specifically designed to handle pre-infusion. Some are designed to control the lever. Some come with a combination of both, like the E61. This is a favorite among baristas as it provides a variety of advantages in a single package.

As you can see in the above photo, the group head is equipped with several notches. The portafilter is placed into these notches and turn the head around to secure it. There is also a gasket of rubber which is located inside the notches and helps create the seal when you insert your portafilter into the machine. The notches allow for precise placement of your portafilter. This is vital for an efficient extraction.

Apart from allowing you easily connect your portafilter, the group head is responsible to maintain an even temperature. This is accomplished by cycling hot water around the portafilter, and through the brew-basket, ensuring that the temperature is constant to extract the coffee. It is important to remember that even a small differences can make the distinction between a great and a excellent espresso coffee machines for sale.

The Pump

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

Pumps are typically more affordable and last longer than piston-driven machines. However, both types of machines can degrade due to excessive use and best cheap Espresso machine poor cleaning. Pumps are also more complicated mechanically, and can add to the cost of even most basic models.

Certain espresso machines remove the pump completely and instead utilize steam pressure to make espresso. This can result in over-extraction because the boiler that makes steam also causes the water to boil. In addition these machines typically have to rebuild their pressure between cups, which takes time and energy.

A majority of espresso machines utilize the rotary or vibration pump. A vibration model makes use of a rotating disk to generate pressure, whereas a rotary model pushes hot water through the ground at a rapid speed. Both machines can make great espresso, however rotary machines are quieter, more durable and less likely to break down.

The Boiler

The boiler makes the water warm to the ideal temperature for extraction. The steam created gets to the portafilter which holds the espresso grounds. It is then funneled 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 one of the main characteristics of a great espresso.

There are three different types of espresso machines, each with a different type of pump and brew temperature. There are various ways to control the brew as well as the size of cup that can be produced by the machine.

The first espresso machines were steam type. They utilized one boiler to create both brew and steam, but the pressure they could produce was very low - just two bars of atmospheric pressure maximum. This led to the coffee tasting bitter and burnt. This is the reason Milanese manufacturers Luigi Bezzerra and Desiderio Pavoni invented the modern espresso machine.

The most popular espresso coffee machines machine is a semiautomatic that has an electric pump. This is what people envision when they think of an espresso maker. Semi-automatic machines require you to grind and tamp your beans yourself, but the pump regulates the water flow and pressure. This is a great compromise between the human touch and the mechanized accuracy.

The Filter

Typically, espresso machines have a filter to separate out the coffee grounds as they pass through the hot water. The filter is also an essential part of the machine's temperature control, as it prevents 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 improves extraction.

However, it is important to keep in mind that even a good filter can produce a bad cup of coffee as the quality of the beans and extraction are vital.

This is where the magic happens, it's what makes espresso taste good. The grouphead (also called the brewhead) is where you put the portafilter, the device that you use to put the grounds of coffee into when making espresso.

In a steam-driven espresso machine, hot water is heated in an airtight tank to produce steam, which then pushes the hot water through the grounds with high pressure. These machines are less expensive and easier to maintain than pumps-driven models. However, they are limited in their ability to create the perfect brewing conditions as they only operate at 1-1.5 bars of pressure. The perfect shot requires 9-10 bar.

In recent years, compressed air pump-driven espresso machines have been gaining popularity. They utilize an air compressor to force the hot water through the grounds and are much more portable than electric steam-driven machines.