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 make the perfect cup of coffee. What exactly does it work?

Espresso is produced by pushing hot water at 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 suggests, the group head is where you put your portafilter in when brewing espresso. It disperses the water into the portafilter, and regulates the pressure during the extraction. There are many different types of group heads, each with its own advantages and disadvantages. Some are designed for stability of temperature while others are built to handle pre-infusion. Some are designed to control the lever. There are some that have a combination of features, like the E61 one, which is the classic choice among many baristas due to its ability to offer multiple benefits in a single package.

As you can see from the above photo the group head is fitted with a variety of notches. It is possible to place your portafilter in these notches and then twist the head to secure it. A rubber gasket is located in the notches to create a seal when you insert your portafilter. The notches permit the precise placement of the portafilter. This is essential for an efficient extraction.

In addition to allowing you to easily connect your portafilter, the group head is responsible for maintaining a consistent temperature. It does this by circulating hot water through the brew container and around the portafilter to ensure that it is always at the right temperature to extract. It is crucial to keep in mind that even a small differences can make the distinction between a decent and a excellent espresso.

The Pump

Motorized pumps in rotary espresso machines provide the nine atmospheric bar pressure required to extract espresso. This is different from manual piston machines that use levers. The pressure builds up by drawing tap water from a reservoir, and pumping it through a heat exchanger before being shot through the ground coffee in the group head.

Pumps are generally less expensive than piston-driven machines and tend to last longer, however both types of machines may get damaged through overuse and lack of cleaning. Pumps are also more complicated mechanically, which could increase the cost of even simple models.

Certain best cheap espresso machine machines do away with the pump completely and instead employ steam pressure to create espresso coffee machines uk. The downside is that the boiler that produces steam also increases the temperature of water until it reaches boiling which can cause excessive extraction. The machines also need to continuously rebuild their pressure between cups. This takes energy and time.

Many espresso machines make use of the rotary or vibration pump, with a vibration model using a rotating disc to generate the pressure and a rotary model pushing hot water through the grounds at high speed. Both types of machine are capable of producing excellent espresso, but the rotary pumps 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 to extract. The resulting steam reaches the portafilter containing ground espresso beans and gets funnelled down into the cup. The steam is able to create enough pressure to push the coffee grounds through. This results in a whipped-up the top of the espresso. This is one of the main characteristics of a good espresso.

There are three distinct types of espresso machines, each with a different type of pump and the temperature of the brew. There are various ways to control the brew as well as the size of cup that can be produced by the machine.

The first espresso machines were steam type. They employed one boiler to make steam and brew, however, the pressure they could create was minimal - two bars of atmospheric pressure at the most. This led to the coffee tasting burnt and bitter. The modern espresso machine was created by the Milanese producers Luigi Bezzerra & Desiderio Pavoni.

The most well-known espresso maker is a semi-automatic device that has an electric pump. When people think of espresso machines, they think of these machines. Semi-automatic machines require you to grind and tamp the beans on your own however the pump controls the flow of water and pressure. This is a great compromise between the human touch and the mechanized quality.

The Filter

Typically, mini espresso maker machines employ filters that separate the grounds of the coffee as they go through the hot water. The filter is also a vital component of the machine's temp control, as it helps prevent overheating.

A filter also helps with flavor since it allows for a longer flowering period. This allows the beans to release their nuances, and allows for better extraction.

It is important to keep in mind that even the most efficient filter can result in a bad cup of coffee. The quality of the beans, and the extraction process, remain vital.

This is where the magic happens. It's what makes an espresso really taste good. The grouphead (also called the brewhead) is where you place the portafilter - the thingy that you use to put the coffee grounds in, while making espresso.

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

In recent times, espresso machines powered by a compressed air compressor have become increasingly popular. They make use of an air compressor to force hot water through the ground and are more mobile than electric steam-driven espresso machines.