Things You'll Need
Powdered sugar is made from crushed granulated sugar, with cornstarch is added to keep it from clumping. Powdered sugar, also known as confectioner's sugar, needs stored properly to prevent lumps from forming. The sugar can also absorb strong odors that can affect the taste. Powdered sugar does not have an expiration date, so as long as you store it properly it will last for a long time.
Pour the powdered sugar into a freezer bag. Remove as much air as possible.
Place the freezer bag into an airtight container.
Place the bagged powdered sugar in a cool, dry location away from humidity. Avoid placing it in the refrigerator because the sugar absorbs odors easily.
Store the powdered sugar in this location, as long it does not form lumps.
Move items in the freezer to make room for the unopened package of powdered sugar. You do not want any heavy objects lying on or against the sugar.
Place an unopened bag of powdered sugar in the freezer.
Remove the powdered sugar from the freezer and thaw it at room temperature.