Storable doesn't store the name of the variable (that would
only be marginally useful, if at all). But what it does store
is the class name of any blessed structure. My bet is that
whatever is stored in the file "func_data" was a hashref
blessed into the class FuncAssociateData. And what
you are storing in "new_func_data" is no longer blessed, so
FuncAssociateData doesn't appear there.