Although most of us are unlikely to go to work without an espresso cup, the question “How does an espresso machine work?” sometimes awakes our curiousness.
Hence, skimming through the article below, you may have an overview of its working system and how your delicious coffee cups are made.
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How Does An Espresso Machine Work? 4 Basic Steps In Process
In its revolution, an espresso machine combined and replaced lots of components, changing from simple to sophisticated design. However, its function theory remains the same from the beginning, based on 4 essential steps: Filling the water source, pumping, boiling, and finally, group heading.
Step 1: Filling the water source
Before opening hours, the barista needs to fill enough water in the machine for many servings. The water source, like blood to human beings, is a vital factor for an espresso machine to function properly, as its main purpose is to provide water for the pump.
There are two flows to fill the water: one is a plumbed connection to a suitable water source, and the other is a water container placed inside the machine.
Each flow is designed to fulfil specific customers’ demands. For instance, to produce just a couple of high-quality espresso cups per day, machines are commonly set with a reservoir. In this way, the bartender can simply adjust the quality of water.
On the other hand, to serve hundreds of cups a day, commercial machines used at coffee shops are plumbed in and rely on the water from the softening and filtration systems. The advantage here is that you no longer have to refill this container.
Step 2: Pumping
After filling the source, water goes through a pumping system before arriving at the boiler. Considered as the heart of an espresso machine, the pump is responsible for transferring water from the container (or the pipe) to mix with the ground coffee beans.
Nowadays, machines using an electric pump are popular. There are two types of pumps: Vibratory and Rotary. The Vibratory pump consists of an electromagnet, a piston, and two springs inside the piston.
Utilizing the electromagnetic principle, when the magnet works, the electromagnetic force will push the connecting rod aside.
Once there is no electricity, the springs will bring the con rod back to its place. In this way, water is transferred through the machine.
Meanwhile, the Rotary pump (similar to your home pump), which is more complicated than the previous one, applies centrifugal force to operate.
Precisely, the engine generates a force to turn the wheel. Once the wheel turns, the centrifugal force created will increase the pressure to push the water flow.
Step 3: Boiling
The next step is to boil and keep the water at the ideal temperature to prepare the best espresso and steam milk. Currently, the most common system which is likely to fulfil both of these activities is a double-boiler espresso machine.
It contains two separate boilers, and water flows in two pipes. The dedicated brew is responsible for filtering espresso and the dedicated steam boils water. A detached remote control optimizes the parameter for each boiler, so the temperature of both is carefully put under control.
To precisely check, some machines are placed with a digital temperature control boiler or PID (Proportional Integral Derivative controller). Both allow the barista to particularly alter and accurately keep the temperature.
Step 4: Group heading
The final station for water to arrive is a metal attachment located in front of the machine, which is in charge of pouring water into the filter basket.
When the barista pushes the outside button to produce a cup of espresso, the group head carries compelled heated water from inside the machine across a diffusion plate, and finally pours into a grounds container.
After sending water through the coffee, the pressure pulls the mixture to the bottom nozzles of the portafilter, and into our coffee cup.
So that is the answer to the question “How does an espresso machine work?”. After skimming through this detailed description, we hope you now have a basic understanding of how a tasty espresso is made for you.