No, coriander powder should not be stored near heat sources. Heat degrades the flavor and aroma of the spice, reducing its quality and shelf life.
Coriander powder, like other ground spices, contains volatile oils that contribute to its characteristic flavor and aroma. These oils are sensitive to heat, light, and moisture. When coriander powder is exposed to heat, these volatile oils evaporate more quickly, leading to a loss of flavor and aroma. Storing it near a stove, oven, or in direct sunlight will accelerate this process. Ideally, coriander powder should be stored in a cool, dark, and dry place, such as a pantry or spice cabinet away from heat-generating appliances. A tightly sealed container is also crucial to prevent moisture from entering and clumping the powder.
To test if your coriander powder is still fresh, rub a small amount between your fingers. If the aroma is weak or non-existent, it's likely time to replace it. Fresh coriander powder has a strong, citrusy, and slightly warm scent.