Cumin is used in Asian cooking and it helps enhance the flavor of foods. Cumin seeds are long brown seeds with a bitter, pungent flavor at times a little sharp. They are quite a strong spice and its not recommended to use too much of them in foods. Cumin seeds when dry roasted give forth a rather unique flavor and can be used to enhance all dishes. These seeds can be added to oil and tempered to flavor dishes. Cumin powder especially those bought from stores will not have the same flavor as fresh cumin seeds. You cannot preserve cumin powder for too long as it has a shelf life while cumin seeds can be stored for many months.