1. Combine the flours, sugar, baking powder, and orange rind in a mixing bowl. Add the remaining ingredients and stir to blend well.
2. Pour into a greased 9x5 inch load pan. Bake at 350F for 45 to 50 minutes. Cool for 6 minutes before removing from the pan.
3. Cool thoroughly on a wire rack. Store in a plastic bag or aluminum foil for at least one day before slicing.