Noticed a hard crust forming on your coriander powder? Learn what causes this to happen and the best way to store it to keep it loose and powdery.
1 Answer
Coriander seed powder forms a crust on top primarily due to moisture absorption from the air and the natural oils present in the spice solidifying upon exposure to air.
Detailed Explanation:
Coriander seed powder, like many ground spices, is hygroscopic, meaning it readily absorbs moisture from its surroundings. When exposed to air, the powder draws in humidity. This moisture dissolves some of the soluble components of the coriander, including sugars and other organic compounds. As the surface layer dries, these dissolved substances recrystallize, forming a hard, crust-like layer. Additionally, coriander seeds contain volatile oils. Upon exposure to air and light, these oils can oxidize and polymerize, leading to a hardening effect on the surface of the powder. The combination of moisture absorption and oil oxidation creates the characteristic crust. Improper storage, such as leaving the container open or storing it in a humid environment, accelerates this process.
Pro Tip:
To prevent coriander powder from forming a crust, store it in an airtight container in a cool, dark, and dry place. Consider adding a desiccant packet to the container to absorb excess moisture.