re: How do you take care of leather?

Since it's a soap, I would think that it is a base, not acidic. It also has keratin or wax and you're supposed to wash it off with a damp rag and then polish, so perhaps that deals with the pH problems.

If you're concerned with those issues, then you should look at the Pecard. A friend of mine works/has worked at several of the NOLA museums. Pecard is what they use on all their stuff.

This saddle at the Cabildo museum is coated in it. Before they applied it, the side flaps were curled upward.