Mussels can be frozen, however, if they are already cooked, the removed meat should be stored in a plastic container. The meat should then be covered in a solution of 1 cup water and 1 teaspoon of salt.
The saltwater solution is referred to as a brine, and instead of freezing cooked mussels in a briney solution, they can be covered in the juice that was used to cook them. Before freezing, uncooked mussels should be lightly blanched for 20 seconds in boiling water. After blanching, the mussels should be drained and placed into plastic containers or freezer bags. Mussels that are frozen in their shells keep for about two months.