10 Quick Tips For Machine Espresso

How Does Machine Espresso Work?

Machine espresso makes use of precise pressure and mind-blowing filter technology to make the coffee we love. What exactly is it?

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

The Group Head

The name implies, the group head is where you insert your portafilter when making espresso. It is responsible for dispersing water into the portafilter and then controlling the pressure that results from the extraction. There are numerous kinds of group heads each with distinct advantages and disadvantages. Some are designed for stability in temperature, while others are designed to handle pre-infusion. Others are made to control the lever. There are even some that have a combination of features, like the E61 one, which is the most popular choice among baristas due to its ability to offer multiple perks in a single package.

As you can see from the photo above the group head is fitted with a variety of notches. You place your portafilter into these notches and twist the head to lock it. A rubber gasket is located in the notches to create a seal when you insert your portafilter. The notches on the head allow for a precise positioning of the portafilter which is vital for an efficient extraction.

In addition to allowing you to easily connect your portafilter, the group head is responsible to ensure that the temperature remains even. It does this by circulating hot water through the brew container and around the portafilter to ensure that it's always at the right temperature to extract. It is important to note that even a slight differences can make the distinction between a good and excellent espresso.

The Pump

The motorized pumps in rotary espresso machines provide the nine atmospheric bars of pressure required for espresso extraction. This differs from manually operated piston machines that employ levers. The pressure is created by removing tap water from a reservoir, and pumping it through a heat exchanger before it is shot through the ground coffee in the group head.

Pumps are typically less expensive than piston-driven machines, and they tend to last longer, however both types of machines could get damaged through overuse and lack of cleaning. They also add mechanical complexity which can result in an expensive price for even the simplest models.

Some espresso machines do away with the pump entirely and make use of steam pressure to make espresso. The disadvantage of this is that the boiler that produces steam also increases the temperature of the water to the point of boiling which can cause over-extraction. These machines also have to continually rebuild their pressure between cups. This takes energy and time.

A large majority of espresso machines employ a rotary or vibration pump. A vibration model makes use of the vibrating disk to create pressure, whereas a Rotary model pushes hot coffee through the ground at a high speed. Both types of machine can make a great espresso, however the rotary pumps are quieter, and more durable than vibration pumps.

The Boiler

The boiler is the one that heats the water to the perfect temperature for extraction. The steam that is produced is then directed to the portafilter, which is the container that holds the espresso maker barista coffee grounds. It is then poured into the cup. The steam creates enough pressure to push the grounds of the coffee through. This results in a crema on the top of the espresso. This is a sign of a great espresso.

There are three types of espresso machines, each with distinct pumps and the temperature of the brew. There are different 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 machines were steam types. The coffee tasted bitter and burnt. The modern espresso machine was created by the Milanese producers Luigi Bezzerra & Desiderio Pavoni.

The most common espresso machine is a semiautomatic with an electric pump. These are what people imagine when they think of an espresso machine. With a semi-automatic espresso machine, you grind the beans and tamp them by hand. The pump controls the flow of water and pressure. This is a perfect combination of human control and mechanised accuracy.

The Filter

Typically, espresso machines have filters that separate the grounds of coffee when they pass through the hot water. The filter is also an essential part of the machine's temperature control, since it helps to prevent overheating.

Filters also aid in flavor since it allows for a longer flowering period. This helps the beans to let their nuances out and provides an opportunity for a better extraction.

It is important to keep in mind that even the finest 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, it's the thing that makes espresso taste great. The grouphead, also called the brew head, is the place where the portafilter (the thing you put the coffee ground into) is placed when you're making espresso.

Steam-driven espresso machines make use of hot water that is heated inside an airtight container to produce steam. The steam then pushes hot water through the grounds of coffee under high pressure. These kinds of machines are generally less expensive and easier to maintain than pump-driven models. However, they are not as efficient in their capacity to create the ideal brewing conditions, since they are only operating at 1-1.5 bars of pressure. The perfect shot requires 9-10 bars.

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