Heat, light, air, and moisture speed up the loss of aroma in many spices. Storage location is therefore just as important as the container.
Dried and ground spices
Store them in tightly closed containers away from the stove and direct sunlight. Use a dry spoon so steam or moisture is not introduced into the container.
Whole spices hold their aroma longer
When practical, store some spices whole and grind them as needed. A smaller exposed surface area reduces contact with air.
Wet spice pastes
Onion, chili, or blended spice pastes should be refrigerated in clean containers and dated. For longer storage, freezing in small portions makes them easier to use.
Watch for quality changes
Discard ingredients that show mold, abnormal odors, excessive moisture, or contamination.