If ever there was a universal coffee maker, I think the moka pot fits the bill. It is also known as caffettiera “coffee maker” or macchinetta del caffè “small coffee machine”, or “Italian coffee pot.” For such a relatively simple devise it provokes a passionate response. I mean really, it is a stove. top. coffee maker. Thats it. But what it does, it does very well, by passing hot water pressurized by steam through ground coffee, ever since it was first patented by inventor Luigi De Ponti for Alfonso Bialetti in 1933. How passionate, you might ask skeptically? How about the fact that it is on display in such museums as the Museum of Modern Art, the Cooper–Hewitt, National Design Museum, the Design Museum, and the London Science Museum, my stove top?
How the heck does it work?
The boiler (the bottom portion) is filled with water to a marker and the funnel-shaped metal filter is inserted. Then the upper part with the second metal filter at the bottom, is tightly screwed onto the base. The pot is placed on stove burner, the water is brought to the point where steam is emitted from the boiler and forced through the coffee in the first filter continuing through the second filter into the upper chamber where the coffee is collected.
As with percolators, the pot should not be left on the stove so long that the coffee boils. Ideally, with a little practice it should be removed from the heat before it actually starts gurgling – usually, when only about half of the top chamber has been filled.
Bring on the Competition
Moka coffee vs. drip coffee
The flavor of Moka pot coffee depends greatly on bean variety, roast level, grind, and the level of heat used. Due to the higher than atmospheric pressure involved, the mixture of water and steam reaches temperatures well above boiling causing a more efficient extraction of caffeine and flavors from the grounds, and resulting in a stronger brew than that obtained by drip brewing.
Moka coffee vs. espresso coffee
Moka pots are sometimes referred to as stove-top espresso makers and produce coffee with an extraction ratio similar to a conventional espresso maker. Depending on bean variety and grind selection, Moka pots can create a foam, known as crema, also found on properly made espressos. However, the maximum pressure for coffee extraction which can be achieved with a Moka pot is 1.5 bar. If you really want to get picky about it, and the folks at the Italian Espresso National Institute and the Specialty Coffee Association of America do get a bit technical here – an espresso must be made using a precise extraction pressure of 9 bar. Ergo while similar, a Moka coffee ≠ true espresso. Nice to know, as I’d been mistakenly referring to it as a stove top espresso maker for far too long.
Moka Preparation – Types I’ve used and seen consistently suggested
While the process is simple to understand, the finer points are what make all the difference. First, we need to start back at the very beginning with the coffee grind. If grinding coffee is the way to go, set the home grinder to “medium”; too fine of a grind (espresso like) results in a burnt and bitter taste from water passing through the ground coffee too slowly, causing over-extraction. Conversely beans ground too coarsely (of the French press consistency) produces an overly light body and sour taste, because the water passes through the grounds too quickly leading to under-extraction.
Also important: do not tamp the coffee in the filter. If you do, the pressure won’t be sufficient for the rest of the process to work properly, leading to that dreaded over-extraction. If you prefer a stronger flavor profile, fill up the filter up to its capacity, and fill the lower chamber with cold water up to the valve or marked line, and set the burner on a low flame.
Critical final step: turn off the flame when the upper section is half full, to avoid overheating and burning the coffee. (Peek in carefully as coffee is still coming up through the middle column and it splatters). As the water approaches boiling, which you don’t want to happen, the process rapidly accelerates, extracting bitter, unpleasant burnt flavor, and upsetting the beautifully balanced aromatic equilibrium the Moka method is known for.