How did Egyptians discover that salt was a preservative?

Egyptians likely discovered that salt acted as a preservative through observation of its effects on food stored in salt-rich environments, such as the Nile delta. They noticed that salted fish and meats lasted longer without spoiling, leading them to use salt for preserving food during long journeys or for storage. This practice became essential in their culture, particularly for mummification and food preservation, highlighting the importance of salt in ancient Egyptian life.