To protect the pecan’s rich oils and buttery taste, do not store shelled pecans at room temperature. For the best quality, always keep your shelled pecans in the
refrigerator. They’ll keep for about nine months in an airtight container, and up to two years in a sealed plastic bag in the freezer. Pecans can be thawed and frozen repeatedly during the two-year freezing period without loss of flavor or texture. You do not need to thaw pecans before using them in recipes. However, it’s best to let frozen pecans reach room temperature if you want to grind them for pecan meal. For in-shell pecans, you can store them in a cool, dry place for up to a year