Real Simple provides a useful guide to how long dozens of products last. Some examples:
• Ketchup
Unopened: 1 year (After this time, color or flavor may be affected, but product is still generally safe to consume.)
Opened or used: 4 to 6 months (After this time, color or flavor may be affected, but product is still generally safe to consume.)• Pickles
Unopened: 18 months
Opened: No conclusive data. Discard if slippery or excessively soft.• Tabasco
5 years, stored in a cool, dry place• Batteries, alkaline
7 years• Lipstick
2 years
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