Why does salt have an expiration date?

Salt is an incredibly common ingredient that most of us take for granted. It is a simple inorganic molecule (meaning “not carbon-based”) made up of two tiny ions, sodium and chloride, but its ability to aromatize and preserving is what makes it precious – so precious that it has made its way into the word “salary”.

Salt preserves food by removing moisture, suppressing the growth of harmful bacteria and encourage the growth of beneficial bacteria–so why do the cans of this product come with expiration dates?

The culprit is not the sodium chloride, but the additives that some manufacturers mix in it to prevent clumping or add nutrients. Iodine, anti-caking agents and trace elements in pink, red or black salts can degrade over time, but degradation does not guarantee damage. Additives may not do their job as well – your salt may start to clump together and you won’t be able to rely on it as a reliable source of iodine – but the less effective iodine won’t hurt you, and you still shouldn’t. Don’t see any mold in your salt shaker.

However, that does not mean that you should neglect your salt, even without additives, or store it in any way. The hygroscopic (water-absorbing) properties of salt make it a poor candidate to be left in the open. Not only can it absorb moisture from the air, but also odors from your kitchen, which can leave you with lumpy and smelly salt.

Store your salt in an airtight container and store it in a dark, cool place. If, like me, you keep salt in a salt pork or other container near the stove, resist the urge to keep it full at all times, and keep an eye on it to make sure it doesn’t get contaminated with it. pieces of food, splashes of water or oil, or other kitchen ephemera.

And, as with everything in your kitchen, throw your salt if you see bugs or mold. While neither thrive in pure salt, kitchens are messy places, and even the purest sodium chloride does not live up to the old rotten food, or outright spills.