Slightly OT - I need some help!

I need some help.

It is written on a number of web sites that malic acid in apples is a useful preparation for Liver Flushing because it softens the stones. Indeed it appears to contribute admirable to flushing protocol and the consensus of this site including myself is that it is beneficial.

Has anyone come across an explanation, preferable, bio-chemical to why this should be so?

Brownie points will be awarded for the best answers.

Telman