Burning Questions: Does salt spoil?
GalleriesGood buys for foodies
How long can table salt last in its original packaging, unopened? Ditto for sugar. What do you do if they harden?
The short answer in both these cases is "forever." Neither salt nor white sugar ever goes bad, whether the package is original or sealed. I daresay that if the original excavators of Pompeii had found a box of sugar buried there, they could have used it to sweeten their espresso....