HOW TO CLEAN MUSSELS
Farm-raised mussels are thankfully quite clean to begin with and don’t require the rigorous individual scrubbing-under-water that wild mussels do, but you’ll still have to give them a quick once over.
STEP 1: RINSE AND SCRUB AS NECESSARY
Place your mussels in a colander or bowl in the sink and run them under cold water. Rinse them to get rid of any debris or seaweed on their outer shells. If you feel any muddy spots, rub them off under the water, but you’re very unlikely to with farm-raised mussels.
STEP 2: DEBEARD
Mussels attach themselves to stable surfaces using thin, sticky membranes referred to as “beards.” Again, most farm-raised mussels will come debearded already, but the odds are good you’ll find a couple of stubborn beards left over.
When you find one, grasp it between your thumb and forefinger and pull it downwards towards the hinged-end of the mussel shell. Pull firmly until it comes out and discard. If you have trouble gripping the beard with just your fingers, a dry paper towel can help.
STEP 3: CHECK FOR DEAD ONES
Mussels, clams, and other bivalves tend to gape open when they’re dead, but not all gaping mussels are dead yet. Some of them are just relaxing (or perhaps stressing, if it’s possible for bivalves to do such a thing).
If you happen to spot any gaping mussels in your bowl, you can check for signs of life by picking them and squeezing them a few times or knocking them with another mussel, clack clack clack. The mussel should slowly close itself back up. If it doesn’t, you’ve got a dead one on your hands. Toss it in the trash and move on with your life.
And that’s it! Your mussels are ready to cook in any number of recipes.
Oh, and for the record, you can go ahead and ignore the conventional wisdom that a mussel that doesn’t open after cooking shouldn’t be eaten.
Elize de Kock: If you leave mussels in water they die, only rinse them under running water.
