Dried, ground chilies don't expire in the same way fresh food does when it becomes contaminated by bacteria. So even if you sprinkle your dinner with decade-old dried chili, you're unlikely to become ill. The flavor and quality of spices degrade over time and they lose their kick. Ground spices, including chilies, stay fresh for roughly four years. After that, they're most likely dull and tasteless.

Like ground chilies, whole, dried chili peppers don't spoil and pose a health risk, but they lose their taste and heat with the passage of time. For delicious food, make sure your chilies are fragrant, leathery and a little shiny, not brittle, dry and dull. The oils contained in the chilies are responsible for most of their flavor, so use ones that are less than six months old for the best result.

To preserve their flavor, store ground chilies in a cool, dry and dark place. Exposure to sunlight, or heat from a refrigerator or other appliance, can diminish the taste of spices. Place whole dried chilies in sealed plastic bags and keep them in the freezer to preserve their oils, which also keeps them safe from pests. You can also keep them in a pantry.

If you can't take too much heat, remove the seeds from whole dried chilies before cooking with them. Chilies that are freshly ground when purchased are likely to be tastier than those that are already ground. If possible, buy chilies in small quantities more frequently. To avoid irritating your skin, wear plastic gloves when cooking with dried chili and always wash your hands after handling them.