How do moka pots work?

The moka pot, also known as a stovetop espresso maker, uses basic physics to achieve a perfectly brewed cup of coffee. It consists of three chambers; one for water, one for the coffee grounds and one for the finished blend.

When the moka pot is placed on the stove, the water heats up and generates steam. This increases the pressure in the bottom chamber and pushes the water up through the coffee granules and into the top chamber where it is ready to be poured.

The pressure built up in the pot’s chambers reach only 1.5 bars, nowhere near the nine bars achieved in traditional espresso makers. Nevertheless, the simplicity of its design and ability to produce quality cups of coffee made it a hit in households.

It was invented in the 1930s by Alfonso Bialetti, who was said to be inspired by observing his wife doing laundry. Their primitive washing machine consisted of a bucket of soapy water that was brought to the boil over the fire. The water was pushed out of the tube and onto the dirty clothes. Bialetti developed a similar technique for the coffee pot and his design remains much the same to this day. Since its first release in 1933, over 300 million pots have been sold around the world and it remains a staple among coffee enthusiasts everywhere.

Inside a moka pot
Inside a moka pot

Born out of fascism

Bialetti’s pot emerged during Benito Mussolini’s regime, when Italy was in a stage of militarisation and its imports and exports were tightly controlled. The bauxite ore necessary for aluminium were native to Italy, and so were favoured by the fascist regime over other imported metals. Accordingly, moka pots were made from this ‘national’ metal, and so were cheap and quick to produce. Additionally, the Italian invasion of Abyssinia (modern Ethiopia) in 1935 brought with it the African country’s rich coffee plantations. This fuelled an already coffee- obsessed country with even more of the precious beans and the patriotic pot was the perfect vessel to cook them in. In the post-war period the pot found international success in Central Europe and the wider Latin world.

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