The Mystery of the Shrieking Moka
The moka pot is a classic. The espresso hits just the right note of bitterness without being too acidic, and you don’t have to stand around fidgeting with switches or pod-things unless you really, really want to. It doesn’t look like a science kit while it’s not in use, adding a little bit of old-world charm to any kitchen.
But my moka pot developed the habit of screaming - - shrieking, really, a steamy howl that became scarier by the day.
I’d attributed this an uneven grind after I found half, whole, and quarter beans in the metal basket (B in the diagram), and then created a mental image of sinister bean shards creating a whistling sound. And then I would make sure that they weren’t in the basket the next time I made espresso.
This had no effect. The shrieking got louder by the day, and it became clear to me that I needed to do something in the event that my neighbors stopped by to ask what the horrible bansheeing was about.
After a fair amount of digging around on the internet, I realized that the logical culprit - - not something that I just imagined - - was espresso residue in the flue of the moka pot. Thus far, soaking the moka in 50% to 50% solution of water and white vinegar seems to scare away the banshees.
Of course, as with everything coffee related, there is controversy. Cleaning the Moka is supposed to result in a less cofffee-like taste. From Wikipedia:
It is said to be desirable to retain this residue, as it subsequently prevents coffee from acquiring an unpleasant metallic taste through contact with the aluminum wall.
Yeah, I did not find this to be the case, but it’s certainly a romantic notion. Although not half as romantic as a morning without screaming. [ Moka Pot on Wikipedia ]