Does Zurek spoil

Does Zurek, the soup, spoil? I mean, it's pure acid just sitting in a pot. How long before the corrosion from the cookware turns it into poison? Asking for a friend.

There are other ingredients and like anything (except a Big Mac) it will spoil. Like all soups you'd need to heat it to boiling every day that it's left in a pan on the stove. And don't forget airborne bacteria settling on top. Treat it like any other soup.

In any case, if it's good żurek, why would it be sitting around for long?

This has always fascinated me. My mother in law is a great cook and will leave a soup on the stove for a long time (possibly overnight although I might be exaggerating ) and will then heat it up again to eat with not a care in the world about food safety. Is that a general polish attitude?

Huh? One day is nothing, unless there is onion in the soup. With onion, it can turn sour overnight. But zurek can stay on the stove for 24h no problem. For longer, put in into refrigerator.

That isn't a long time. Providing there's a lid on the pan, and you don't live somewhere very hot, it's fine.