10 Things That Your Family Taught You About Machine Espresso

How Does Machine Espresso Work?

Machine espresso uses precision pressure and mind-blowing filter technology to create the perfect cup of coffee. What exactly is it?

Espresso is created by forcing hot water under high pressure through finely ground coffee. The process is similar to making drip coffee espresso machine however the main difference lies in the pressure.

The Group Head

As the name implies the group head is the place you place your portafilter when brewing espresso. It distributes water into the portafilter and controls the pressure of the extraction. There are numerous kinds of group heads each with distinct advantages and drawbacks. Some focus on temperature stability, whereas others on pre-infusion capabilities, and still others are designed to control the lever. There are even some that have a combination of features, like the E61 that is the classic choice among many baristas due to its ability to offer multiple benefits in one package.

As you can see in the photo above, the group head has several notches to place your portafilter and twist it manually to lock it in. There is also a rubber gasket that is a part of the notches and helps create an airtight seal when you insert your portafilter into the machine. The notches on the head permit a precise location of the portafilter which is necessary to ensure an efficient extraction.

The group head not only lets you to place your portafilter easily, but it also maintains a constant temperature. This is achieved by cycling hot water around the portafilter, and through the brew-basket, ensuring the temperature is always right to extract the coffee. It is important to note that even a slight difference can make the difference between a good and a great espresso.

The Pump

In contrast to manual piston machines which rely on a lever to pressurize water, rotating espresso machines rely upon motorized pumps to provide the nine atmospheric bars of pressure that are required for espresso extraction. The pressure is created by removing tap water from a reservoir, and pumping it through a heat exchanger prior to it is shot through the ground coffee inside the group head.

Pumps tend to be less expensive than piston-driven machines, and tend to last longer, although both types of machines may be damaged by excessive use and inadequate cleaning. Pumps are also more complicated mechanically, which could increase prices of even most basic models.

Some espresso machines employ steam pressure instead of a pump for brewing espresso. The drawback is that the same boiler that produces steam also raises the temperature of water to the point of boiling which can cause over-extraction. Additionally these machines typically have to rebuild their pressure between cups, which requires time and energy.

A majority of espresso coffee machine machines utilize an rotary or a vibration pump. A vibration model uses a vibrating disk to generate pressure, while a rotating model pushes hot water through the ground at a rapid speed. Both machines can produce excellent discount espresso machines, but rotary machines are more stable, quieter and less likely to break down.

The Boiler

The boiler is the component which heats the water to the optimal temperature to extract. The steam that is produced reaches the portafilter which holds the ground retro espresso machine and is then funneled down into the cup. During this process the steam is able to create enough pressure to push the grounds of coffee through. This results in a layer crema that is then poured over. This is a sign of a good espresso.

There are three types of espresso makers. They differ in the kind of pump they use and the degree of heat that the espresso is. There are various 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-types. The earliest espresso machines were steam-type machines. This led to the coffee tasting burnt and bitter. This is why the Milanese producers Luigi Bezzerra and Desiderio Pavoni invented the modern espresso machine.

The most commonly used espresso machine is a semiautomatic with an electric pump. When people think of espresso machines, they envision these machines. Semi-automatic machines require you to grind and tamp the beans on your own The pump, however, regulates the flow of water and pressure. This is a perfect solution that combines human control with mechanized consistency.

The Filter

Espresso machines usually have a filter that separates the grounds of the coffee from hot water. The filter is also a vital part of the machine's temperature control, as it prevents overheating.

Filters also aid in flavor because it allows for the beans to flower for a longer period of time. This allows the beans to release their flavor and gives the chance for better extraction.

It is important to remember that even the most efficient filter could result in a poor cup of coffee. The quality of the beans and the extraction, remain crucial.

It's in this area that the magic takes place. This is what makes espresso taste so good. The grouphead (also called the brewhead) is where you place the portafilter, the thingy which you put the coffee grounds in, while making espresso.

Steam-driven espresso machines make use of hot water that is heated inside an airtight vessel to create steam. The steam then pushes hot water through the grounds of coffee under high pressure. These machines are less expensive and are easier for the user to maintain than pumps-driven models. However, they are not as efficient in their ability to provide the ideal conditions for brewing as they only operate at 1-1.5 bars of pressure, while the perfect shot requires 9-10 bars.

In recent years, compressed air-driven espresso machines have become more popular. They utilize an air compressor to push hot water across the ground and are more mobile than steam-driven electric espresso machines.