[ELI5] How does salt preserve food?
In: Chemistry
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salt is a desiccant (removes moisture from things) and sodium in high concentrations is toxic to microbes.
Imagine sticking a bunch of sponges on food. Sponges naturally suck out liquid. Inside the liqid there are little animals that munch on the food but now can’t because they’re inside the sponge.
So just like how heat likes to spread out to it’s surroundings, so that everything becomes the same temperature.
When in a solution of high amounts of salt, the water in the bacteria leaves the cell wall to create equal saltiness between the bacteria and the surrounding environment. This kills the bacteria as there is no water left inside of it.
For fermented foods like sauerkraut and Kim-chi, salt+cabbage+culture create an environment where the ‘good’ bacteria thrive and displace ‘bad(rot)’ bacteria.
[Salt: A World History](https://www.theguardian.com/books/2002/feb/16/historybooks.highereducation) is a quick, easy and fun read about how important salt and food preservation are to civilization.
Salt preserves food by preventing bacteria from growing.
There are two main ways salt is used to preserve foods: granule form or in brine, which is a salt-and-water solution. Granule form, or dry curing, is one of the most ancient ways of curing meats.
In both methods, salt prevents bacteria from growing, including foodborne pathogens such as salmonella, which can cause food poisoning, typhoid fever and other serious problems. It does this through salt’s interaction with water.
Salt is a disrupter that causes chaos for microbes, confusing their enzymes and breaking their DNA. It mainly accomplishes this via dehydration, removing the water molecules that bacteria need to live and grow.
Salt dehydrates food through osmosis. The salt the salt around the outside of the food draws water molecules out and replaces them with salt molecules until the amount of salt is equal inside and out.
This prevents bacteria from growing, makes the food last longer.
[source](https://recipes.howstuffworks.com/tools-and-techniques/salt-prevent-food-from-spoiling.htm)
It draws moisture out of things. This dehydrates and suspends or kills microorganisms that would usually want to munch on the preserved food.
salt dries things out, and bacteria generally requires moisture to survive. It draws moisture out of the thing through osmosis (or more elaborately trying to ‘balance’ the moisture between the thing and the salt, but salt has an unnatural property of absorbing liquid in a sponge-like fashion)
Oh, that sparked a question in my head:
How would honey (if ever vanilla case first, then special cases second) preserve food?
So if I don’t have silica gel for my new Jordan’s in the box will this stop the shoe from it from coming apart?
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