When I was a young culinarian, my mom had a large tin of “Jamaican Ginger” that was pulled out of the back of the spice cabinet every year to make a secret Christmas cookie. As the years went on, and on, and on… the secret ingredient became less and less potent.
30 years after the Jamaican Ginger purchase, the tin was finally laid to rest, no doubt out of fears of food safety.
But what about other, less obvious, signs to toss?
Let’s take a step back to flavor basics. Flavor is a combination of the sensations felt on the tongue (salt, sweet, sour, savory, and bitter), and smells in the nose. As food is chewed, the amazing compounds responsible for flavor are released and vaporized. The amazing scent of a steak is actually teeny tiny pieces of steak that have been dissolved in the air. (The knowledge of what smells are makes you think twice about some of the noxious smells experienced.)
Putting it simply, the more flavor compound molecules present in food, the more will be vaporized, and the stronger your food will taste.
As this relates to spices, they are constantly putting off a scent. Flavor molecules are vaporizing. With each passing day, more and more molecules are released from the spice, and the spice becomes less and less potent.
So although a spice never goes bad, it does lose flavor.
A few feneral rules on keeping spices:
Ground spices will lose their flavor fastest, and for maximum potency, they should be replaced every 2 years.
Herbs can be kept for up to 3 years
Whole herbs can go as long as 4 years before their potency comes into question.