The 9 Things Your Parents 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 at high pressure through finely-ground coffee. The process is similar to making drip coffee however the main difference lies in the pressure.

The Group Head

The group head is the portafilter that you place in the espresso maker when making it. It is responsible for dispersing water into the portafilter and controlling the pressure of the resulting extraction. There are many different types of group heads each with distinct advantages and drawbacks. Some are focused on temperature stability, others on pre-infusion options, and others are designed to control the lever. Some have a combination, like the E61. This is a popular choice among baristas due to the fact that it has multiple advantages in a single package.

As you can see in the above photo the group head comes with numerous notches that you can place your portafilter and twist it by hand to secure it. A gasket made of rubber is positioned inside the notches, which helps create a seal when you insert your portafilter. The notches on the head allow for an exact positioning of the portafilter which is essential to ensure an even extraction.

The group head not only lets the portafilter to be inserted easily however it also keeps a constant temperature. This is accomplished by cycling hot water around the portafilter and through the brew-basket to ensure that the temperature is constant to extract the coffee. It is important to remember that even a slight differences can make the distinction between a good and a great espresso.

The Pump

Motorized pumps in rotary espresso machines supply the nine atmospheric bars of pressure required to extract espresso. This differs from manual piston machines which use a lever. The pressure is created by drawing tap water from a reservoir and pumping it through a heat exchanger before being pushed through the ground coffee in the group head.

Pumps are generally less expensive and last longer than piston-driven machines. However, both types of machines may degrade due to excessive use and inadequate cleaning. Pumps are also more complicated mechanically, which can increase the cost of even most basic models.

Some espresso machines eliminate the pump completely and make use of steam pressure to make espresso. The drawback is that the boiler that produces steam also increases the temperature of the water to boiling, which can lead to over-extraction. Additionally, these machines espresso frequently have to rebuild their pressure between cups, which takes time and energy.

Many espresso machines employ the rotary or vibration pump, with a vibrating model using a rotating disc to create pressure and a rotary model pushing hot water through the grounds at high speed. Both machines can make excellent decent espresso machine, but rotary machines are more stable, quieter and less likely to break.

The Boiler

The boiler will heat the water to a temperature that is ideal for extraction. The steam that is produced reaches the portafilter that contains ground espresso beans and is then pumped into the cup. During this process the steam creates enough pressure to push the grounds of coffee through. This produces a layer of crema on top. This is a hallmark of a good espresso.

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

The first espresso machines were steam type. The earliest espresso machine black friday machines were steam types. The coffee tasted bitter and burnt. This is the reason Milanese makers Luigi Bezzerra and Desiderio Pavoni created the modern espresso machine.

The most common espresso maker is a semi-automatic device with an electric pump. When people think of espresso machines espresso machines, they think of these machines. If you have a semi-automatic machine you grind the beans and then tamp them by hand, but the pump regulates the flow of water and pressure. This is a great compromise between the human touch and mechanized accuracy.

The Filter

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

A filter also helps with flavor, as it permits the beans to flower for a longer period of time. This allows the beans to release their flavor and allows for a better extraction.

However it is crucial to remember that even a great filter can result in a poor cup of coffee, since the quality of the beans and extraction is crucial.

This is where the magic happens, it's what makes espresso taste good. The grouphead, sometimes referred to as the brew head, is the place where the portafilter (the thing you put the ground coffee into) is located when you're making espresso.

In the steam-driven espresso machine hot water is heated in an airtight container to create steam. This is then pushed through the grounds at a high pressure. These machines are cheaper and easier for the owner to maintain than pumps-driven models. However, they are limited in their capacity to create the ideal conditions for brewing since they operate at 1-1.5 bars of pressure, while the perfect shot requires 9-10 bar.

In recent years, espresso machines driven by a compressed air compressor have become increasingly popular. They utilize an air compressor to push hot water through grounds and are more portable than electric steam-driven machines.