How can a sourdough starter be 100 years old?

Question

I keep seeing sourdough starters all over socials. How can sourdough starters be many years old. Don’t you need to use the starter to make the bread? ELI5!

In: Other

Answer 1

You can definitely google this very easily. But for the sake of an answer, however brief: you only use a tiny amount of the starter per loaf. Then you replenish the starter with more flour and water.