Wrap properly

Use only moistureproof wrappings, such as aluminum foil, airtight plastic containers, and resealable freezer-weight plastic bags. Choose plastic containers that can be filled almost to the brim with liquids such as stock or soup; leave some room for expansion but not so much that the container holds excess air. Other foods should be enclosed in a double layer of wrapping, and as much air as possible should be expelled before sealing.