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Salt was discovered thousands of years ago as a way of preserving food. How does it do this? And what else does salt preserve?Key facts
- Food rots because of bacteria and fungi.
- Salt is an effective preservative because it inhibits the growth of bacteria.
- The Egyptians discovered that salt could preserve their food, and it was also used in mummification.
- Osmosis is the movement of water across a concentration gradient.
Transcript
Food rots because of bacteria and fungi.
These microorganisms thrive in the water within food, which makes up as much as 50% of food like tomatoes.
So, one of the keys to preserving food for longer lies in extracting the water content from it, to inhibit bacterial growth.
It was the Egyptians …
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