The moka pot's construction has changed little in its 80-year history. Moka pots typically are made from aluminum or stainless steel. The base of the pot (or "boiler") holds the water. The funnel-shaped chamber in the middle of the pot contains the filter for the coffee grounds, and the top chamber collects the brewed coffee. To make coffee, fill the boiler with hot water, place the middle chamber on top and add coffee grounds.
Screw the top chamber on tightly and set the pot over a heat source. The heat causes the water to boil, which in turn creates steam and pressure. The pressure pushes the water down, and with nowhere else to go, the water is eventually and gradually pushed upward. Water travels up the tube in the funnel, through the coffee grounds, and then to the holding chamber once it has become coffee.
Although it is sometimes referred to as a stovetop espresso maker, a moka pot can't make espresso because the pressure it produces is not great enough to extract espresso. The maximum pressure achieved with a moka pot is roughly 1.5 bars, whereas traditional espresso machines extract coffee using 9 bars of pressure.
Moka pots are resurging in popularity. This comes as no surprise, as they can cost as little as 10 dollars, are easy to clean and portable, and they can be used over a campfire just as easily as over the stove. Also adding to its charms is the moka pot's timeless quality and ability to be passed down for generations.
Steve Kirbach, head roaster at Stumptown Coffee Roasters in Portland, Ore., offers these tips for brewing coffee in a moka pot:
- For best results, start by adding hot water to the boiler. This prevents the coffee grounds from "cooking" while the water warms up, which can lead to a bitter, metallic brew.
- Use a medium-grind coffee, which is not as fine as the grind used for espresso and not as coarse as that used for a French press.
- Don't press or tamp grounds into the filter. This can prevent sufficient pressure from building and impairs the extraction process.
- Use moderate heat and watch your coffee brew. Once the coffee streaming out into the top chamber has become the color of yellow honey, remove the pot from the heat source and close the lid.
- After removing the pot from the heat, wrap it in a cold towel or run under cold water to stop the extraction process.
There's more than one way to make a cup of coffee, but few are as timeless as the modest, hourglass-shaped moka pot. Invented in Italy in 1933 by Alfonso Bialetti, the moka pot was developed as an inexpensive way to brew good coffee during an economic slump. Bialetti found inspiration for the moka pot looking no further than his own washing machine. Observing the washing machine's mechanics, Bialetti deduced that a similar system could work to brew coffee.