14 Cartoons About Machine Espresso That'll Brighten Your Day

How Does Machine Espresso Work?

Machine espresso employs precise pressure and mind-blowing filter technology to make the delicious coffee we enjoy. What exactly does it work?

In order to make espresso hot water is forced 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 Group Head

As the name implies the group head is the place you put your portafilter in when making espresso. It is responsible for dispersing the water into the portafilter, and controlling the pressure of the extraction. There are many different types of group heads each with distinct advantages and drawbacks. Some are focused on temperature stability, while others on pre-infusion capabilities, while others are designed to control the lever. Some have a combination, like the E61. This is a preferred choice for baristas because it offers multiple advantages in a single package.

As you can see from the above photo the group head is fitted with several notches. The portafilter is placed in these notches and then turn the head around to secure it. A gasket made of rubber is positioned inside the notches, which helps create a seal as you insert your portafilter. The notches allow for precise placement of the portafilter. This is crucial to ensure an even extraction.

Apart from allowing you effortlessly insert your portafilter the group head is also responsible to maintain an even temperature. It does this by cycling hot water through the brew container and around the portafilter, making sure that it's always at the right temperature to extract. It is important to note that even a slight deviation can make the difference between a good and a excellent espresso.

The Pump

The motorized pumps used in rotary espresso machines supply the nine atmospheric bars of pressure required to extract espresso. This is different from manual piston machines that rely on levers. The pressure builds by drawing tap water from a reservoir and pumping it through a heat exchanger prior to being shot through the ground coffee in the group head.

Pumps are typically cheaper and last longer than piston-driven machines. However, both types of machines can deteriorate due to overuse and insufficient cleaning. They also add mechanical complexity, which can result in the cost of even the simplest models.

Some espresso machines remove the pump completely and make use of steam pressure to make espresso. The downside is that the boiler that produces steam also raises the temperature of the water until it reaches boiling which could lead to excessive extraction. They also have to constantly rebuild their pressure in between cups. This requires energy and time.

Many espresso machines utilize an rotary or vibrating pump, which is a vibration model that uses a vibrating disc to create the pressure and the rotary model pushing hot water through the grounds under high speed. Both machines produce great espresso, but rotary machines are more quiet, durable and less likely to fail.

The Boiler

The boiler is the element that heats water to the ideal temperature to extract. The resultant steam then reaches the portafilter, which contains the ground espresso coffee, and is then pumped into the cup. During this process, steam creates pressure and pushes through the grounds of the coffee. This results in a whipped-up the top of the espresso. This is one of the hallmarks of a great espresso.

There are three kinds of espresso makers, and they differ in the kind of pump they use and the degree of heat that the espresso is. There are different ways to control the brew as well as the size of the cup that can be produced by the machine.

The first espresso machines were steam-types. The earliest espresso machines were steam types. The coffee tasted bitter and burned. This is the reason Milanese makers Luigi Bezzerra and Desiderio Pavoni developed the modern espresso machine.

The most commonly used espresso machine is a semiautomatic one with an electric pump. These are what people imagine when they think of an espresso maker. Semi-automatic machines require you to grind and tamp the beans on your own while the pump controls the water flow and pressure. This is a great compromise between the human touch and mechanized consistency.

The Filter

Espresso machines typically have filters that separate the grounds of coffee from hot water. The filter is also an essential element of the temperature control system, as it prevents the machine from overheating.

A filter also helps with flavor, as it permits an extended flowering time. This allows the beans to release their nuances, and improves extraction.

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

This is where the magic happens, and it's what makes an espresso really taste great. The grouphead (also called the brewhead) is where you place the portafilter - the thingy which you put the coffee grounds into, when making espresso.

Steam-driven espresso machines make use of hot water that is heated in an airtight vessel to create steam. The steam then pushes hot water into the coffee grounds under high pressure. These types of machines are generally cheaper and easier to maintain than pump-driven models. However, they are limited 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 bar espresso machine-10 bars.

In recent years, espresso machines powered by compressed air-pump are becoming increasingly popular. They utilize an air compressor to force hot water through the ground and are much more mobile than electric steam-driven espresso machines.