There is a commercial/industrial ingredient that has been developped to solve that problem i.e. lowering acidity without adding too much flavour (like lime juice and vinegar): It is called Gluco Delta Lactone of GDL.
see here;
Glucono delta-lactone - Wikipedia, the free encyclopedia
Personally I would go with lactic acid which is the predominant acid in sour dough bread. Tastewise it is closely related to bread then the other acids mentionned.
hope this helps^
Luc H.