Does salt really "expire"

[Sarah]

In going through my salt supply for turkey brining, I found some w/shockingly old dates and wondered if salt really expires or loses its strength -- kosher, coarse sea salt, sel gris, sea star brittany gray, etc.

[Cherylptw]

Salt is one of those things that never goes bad or loses its potency...I have salt that I've had at least five years..as long as it stays dry it's good.

[monku]

How can it "expire"....this Himalayan Sea Salt is 250 million years old.
http://www.natural-salt-lamps.com/edi...

[Muskrat]

So if Sarah holds on to her salt for 250 million years, it'll really be worth something!

[monku]

Not sure, this company claims their underground salt is 280 million years old.
http://www.alibaba.com/product-free/1...

[hsk]

No, it doesn't. Where were the "shockingly old dates" - I've never seen "best before" dates on salt. It's a chemical compound (yes, even the expensive ones) that's pretty stable, as long as you store it properly it won't change over time.

[Sarah]

Among others, I have an unopened box of Morton's Coarse Kosher Salt, undated -- and a container of fin sel gris marked on bottom w/ lot number 2900 12/2004. They have been stored in a cabinet undisturbed all these many years.

[hsk]

That's just when it was packed. Not a "best before" date. All salt is fine even if you've had it for years. Just if it's old and improperly stored it might be more like a block. It's still fine to use, you just might have to chip off pieces :)

[ricepad]

Salt is a rock. Ever seen a rock with a freshness date?

[Melanie Wong]

Those dates might be he expiration dates of the packaging's integrity, e.g., ability to keep moisture out, etc. to hold the salt in its original condition.

[monku]

The date is probably when the salt was packaged and the lot # identifies where and when that batch was harvested.

[Melanie Wong]

Actually I just looked at some smoked salt I have on hand. It has a date of 8/2009, and I know that I purchased it in 2008. So in this case, not a packaging date.

[hsk]

Probably a clever marketing ploy to sell more product. Although maybe smoked salt loses its smokiness over time (I've never tried it). It definitely wouldn't lose its saltiness.

[gabes_human]

Since salt is used as a preservative that should tell you something. It was one of the few methods for preserving food before refrigeration and it worked since there are few microbes (and they mostly live at deep-sea thermal vents) with cell walls that can survive heavy doses of salt. The worst that could happen to your brine mixes is that any herbal additions may have lost their flavour.