Salt: Food Preservative

The video explains how microorganisms thrive in the water content of food, which can be up to 50% in items like tomatoes. To preserve food, water content must be reduced to inhibit bacterial growth. The Egyptians discovered that salt, found in sand, was effective in preserving bodies and later food. Salt, mainly sodium chloride, works by drawing water out of bacterial cells through osmosis, preventing their growth. This method requires reducing food's water content to about 0.91%. Salt has been used for preservation throughout history and remains a key method today.

What is osmosis and how does it relate to food preservation?

What is the required water percentage for many bacteria to be unable to grow?