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

Sourdough starter more accurately is kind of like keeping a culture of bacteria as a pet. You feed that pet and maintain its environment and then in turn you use a small portion of it to make your bread while the rest of it continues to breed and continue living on.

Technically none of the bacteria in there is the same bacteria from 100 years ago but this specific culture has been fed and maintained for that entire time If that makes sense.