Salt is that one natural preservative, which never ages. Yes, this is the reason why it has been used in preserving foods like pickles, chutney, dry snacks. However, this is only when the salt is not fortified with iodine or other additives, which may tend to change the natural properties of the salt. Since salt is extracted from seawater, it never loses its real flavour. However, to avoid clumping up of salt, it is fortified with additives which reduces the shelf life to 5-6 years.
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