Yes, mustard powder does eventually lose potency and flavor, although it doesn't spoil in the same way perishable foods do. It's a shelf-stable spice, but its quality degrades over time.
Shelf Life and Storage
- Unopened: Unopened mustard powder can retain its peak quality for 3-4 years when stored properly in a cool, dark, and dry place. Some sources suggest even longer, up to two years on the shelf, and indefinitely when refrigerated. [Source: Multiple sources including Texas Real Food, Reddit Cooking Subreddit, and various other online sources]
- Opened: Once opened, while not technically "going off," the powder's potency will diminish more quickly. It's best to use it within a reasonable timeframe after opening to maintain optimal flavor.
Factors Affecting Shelf Life
- Storage: Proper storage is crucial. Keeping mustard powder in an airtight container in a cool, dark, and dry place will significantly extend its shelf life and prevent it from absorbing moisture or odors.
- Exposure to air and moisture: Exposure to air and moisture accelerates the loss of flavor and potency.
Signs of Deterioration
While mustard powder doesn't spoil like meat or dairy, it will lose its pungency over time. There's no single definitive sign, but a noticeable reduction in its characteristic sharp flavor is a good indicator that it's past its prime.
In Summary
Mustard powder won't make you ill if consumed past its peak, but its flavor and potency will decline over time. Proper storage significantly extends its usability.
