Spices that are past their prime won’t make you sick, but they won’t have much flavor either, says Patty Erd, the owner of the Spice House, a small chain of specialty spice stores in Illinois and Wisconsin. To get the most from what you’ve got, she suggests keeping whole spices for three years and ground spices for just a year. When a spice is ground, it releases the oils responsible for its flavor and aroma. As the oils dissipate, the spice becomes less pungent.
To test the freshness of a spice, the McCormick company suggests you look first at the color, then crush the suspected antique in your hand to check for good aroma and flavor. If the color, smell, and flavor are weak, toss it. McCormick also has a website that allows you to enter the dates or codes from its spice jars to check for freshness. Spice Islands offers a similar service.
You can help your spices retain their flavor by storing them correctly. “The enemies of fresh spice flavor and color are heat, light, air, and moisture” reads one tip from the website of Morton & Bassett, a spice company based in the San Francisco Bay Area. The company recommends storing spices in airtight containers away from sources of light and heat (like your stove, dishwasher, or microwave). Erd suggests using dark-colored glass containers for storage, and says you can double the life span of your expensive spices by keeping them in the fridge.