Not the bean juice!

It's an untreated byproduct that you normally discard. Every culture that eats beans has discarded their bean rinse water; you don't really see recipes that have you cook the beans in their own rinse. Canned beans have been a thing for a century or more but there's a good reason why bean wastewater was only "discovered" by some random guy 10 years ago.

Saponins and other stuff in there are cool for industrial processes but you don't really want to ingest them.