Mix dry ingredients together; stir in nuts and zucchini.
To beaten egg whites add the orange juice and oil.
Fold into dry ingredients and add orange peel.
Spoon into greased and floured 9 x 13 x 2 inch pan.
Bake at 350Â° for 40 to 45 minutes or until toothpick inserted in center comes out dry and clean.
Cool; cut into squares.
Can be drizzled with thin orange icing if desired.