11 Methods To Totally Defeat Your Machine Espresso

How Does Machine Espresso Work?

Machine espresso makes use of precise pressure and incredible filter technology to produce the coffee we love. What exactly is it?

To make an 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 Head of the Group

The name implies the group head is where you insert your portafilter when brewing espresso. It is responsible for dispersing water into the portafilter, and controlling the pressure that results from the extraction. There are a variety of group heads each with its own advantages and disadvantages. Some focus on temperature stability, some on pre-infusion capabilities, and still others are designed to control the lever. Some include a mix of features, like the E61, which is considered the standard choice for many baristas for its ability to offer multiple perks in a single package.

As you can see in the image 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 lock it. There is also a gasket of rubber in the notches and helps to create a seal when you insert your portafilter into the machine. The notches on the head allow for an exact position of the portafilter which is necessary for a consistent extraction.

Aside from allowing you to easily place your portafilter in, the group head is responsible to maintain an even temperature. This is accomplished by cycling hot water around the portafilter and through the brew basin, ensuring that the temperature is constant for extraction. This is important because even a few degrees can make the difference between good and great espresso.

The Pump

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

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

Certain espresso machines eliminate the pump entirely and make use of steam pressure to make espresso. This can result in over-extraction because the boiler that produces steam also heats the water until it comes to a boil. Additionally these machines typically have to restore their pressure between cups, which requires time and energy.

Many espresso machines utilize a vibration or rotary pump, with a vibration model using a vibrating disc to create pressure and an rotary model that pushes hot water through the grounds at high speed. Both machines can make great espresso, but rotary machines are more stable, quieter and less likely to break.

The Boiler

The boiler will heat the water to the ideal temperature to extract. The resulting steam is then transferred to the portafilter which holds the ground espresso and is mini espresso machine then pumped into the cup. During this process the steam causes enough pressure to push the grounds of coffee through. This produces a layer of crema on top. This is one of the main characteristics of a good espresso.

There are three types of espresso makers. They differ in the kind of pump they use and how hot the brew is. There are various ways to control the brew and the size of the cup that can be made by the machine.

The first espresso machines were steam-based. The earliest espresso machines were steam types. This resulted in the coffee tasting bitter and burnt. This is the reason why Milanese makers Luigi Bezzerra and Desiderio Pavoni created the modern espresso machine.

The most common espresso maker is a semiautomatic machine with an electric pump. This is what people envision when they think of an espresso machine. Semi-automatic machines require you to grind and tamp the beans yourself The pump, however, regulates the water flow and pressure. This is a great compromise between the human touch and mechanized quality.

The Filter

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

It also improves flavor, since a filter allows for a more prolonged bloom phase. This allows the beans to release their flavors, and allows for a better extraction.

It is important to remember that even the most efficient filter can make a bad cup of coffee. The quality of the beans, and the extraction process are still crucial.

It's in this area that the magic occurs. This is what makes espresso taste so good. The grouphead (also called the brewhead) is where you put the portafilter, the device that you use to put the grounds of your coffee into when making espresso.

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

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