Nine Things That Your Parent Teach You About Machine Espresso

How Does Machine Espresso Work?

Machine espresso uses precision pressure and mind-blowing filter technology to make the coffee we love. What exactly is it?

Espresso is produced by pushing 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 Head of the Group

The name implies the group head is the place you insert your portafilter when brewing espresso. It is responsible for dispersing water into the portafilter and then controlling the pressure of the extraction. There are several different types of group head each with its own advantages and drawbacks. Some are specifically designed for stability of temperature while others are specifically designed to handle pre-infusion. Others are built to control the lever. Some include a combination such as the E61. This is a very popular choice for baristas due to the fact that it has multiple benefits in a single package.

As you can see in the photo above the head of the group is fitted with a variety of notches. It is possible to place your portafilter inside these notches, and then twist the head to secure it. There is also a rubber gasket that is a part of the notches and helps to create the seal when you insert your portafilter into the machine. The notches permit precise placement of your portafilter. This is essential for an even extraction.

In addition to allowing you to effortlessly insert your portafilter the group head is responsible to maintain an even temperature. This is achieved by cycling hot water around the portafilter, and through the brew-basket, making sure that the temperature is always at the right level to extract the coffee. This is crucial, since even a small difference in temperature can be the difference between a good and excellent espresso.

The Pump

Unlike manual piston machines, which use a lever to pressurize water, rotary espresso machines rely on motorized pumps to supply the nine atmospheric bars of pressure needed to extract decent espresso machine. This pressure builds up by removing tap water from a reservoir, and pumping it through a heat exchanger prior to being pumped through the ground coffee in the group head.

Pumps are typically less expensive than piston-driven machines and tend to last longer. However, both types of machines may become damaged due to excessive use and poor cleaning. They also create mechanical complexity and can lead to an expensive price for even the simplest models.

Some espresso machines remove the pump entirely and make use of steam pressure to make espresso. The drawback is that the same boiler that produces steam also raises the temperature of the water to boiling which could lead to over-extraction. The machines must also constantly rebuild their pressure between cups. This requires energy and time.

Many best espresso maker machines make use of a vibration or rotary pump, which is a vibration model using a vibrating disc to create the pressure and a rotary model pushing hot water through the grounds at high speed. Both types of machine can make a great espresso, but rotary machines are quieter and more durable than vibration pumps.

The Boiler

The boiler is the one that is used to heat the water to a temperature that is ideal for extraction. The resulting steam reaches the portafilter containing the ground espresso coffee, and is then funneled down into the cup. During this process, the steam creates pressure that pushes through the coffee grounds. This creates a foam on top of the espresso. This is a sign of a good espresso.

There are three different types of espresso machines, each having distinct pumps and the temperature of the brew. There are a variety of ways to control the brew as well as the size of cup that can be made by the machine.

The first espresso machines were steam-types. The first espresso machines were steam-type machines. This led to the coffee tasting bitter and burnt. The modern espresso machine was developed by the Milanese makers Luigi Bezzerra & Desiderio Pavoni.

The most well-known espresso maker is a semi-automatic device that has an electric pump. This is what people envision when they think of an espresso machine. With a semi-automatic machine you have to grind the beans and then tamp them by hand, but the pump provides regulated water flow and pressure. This is a great compromise between the human touch and the mechanized quality.

The Filter

Typically, espresso machines use a filter to separate out the grounds of best coffee espresso machine as they move through the hot water. The filter is also an essential part of the temperature control system, because it stops the machine from overheating.

It also enhances flavor, since a filter allows for a longer bloom time. This allows the beans to release their nuances, and allows for better extraction.

It is important to remember that even the finest filter can produce a bad cup of coffee. The quality of the beans, as well as the extraction, are still very important.

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

In a steam-driven espresso machine hot water is heated in an airtight container to create steam, which is then pushed through the grounds at a high pressure. These machines are less expensive and easier to maintain than pumps-driven models. They are however limited to create the ideal conditions for brewing since they only operate with 1-1.5 bar of pressure. The perfect shot requires 9-10 bars.

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