If reusable food storage containers have taken on a smell of something you stored weeks or months ago, there’s no reason to replace it. Simply create a solution of dried mustard powder and hot water, and let it naturally deodorize the container for you. Dry mustard powder has natural antimicrobial properties that can attack stubborn odors and stains. Use a teaspoon to a tablespoon (depending on the size of the container) of dry mustard powder and hot water to activate the mustard's natural cleaning properties. Once you rinse out the solution, your container should be as good as new.