What does "de-bearding" mussels mean?
The beard is also known as byssus threads. They are the filaments that the mussel uses to secure itself to hard surfaces. They are usually brownish and may appear somewhat like seaweed. Most mussels commercially available have been farm-raised so often the beards have already been removed during processing. If you have beards, grasp them firmly and pull towards the shell hinge until it comes out. You may need to use a dry paper towel to increase your grip as they can be slippery.