Preheat oven to 350°F.
Stir together flours, baking powder, baking soda, salt, cinnamon, ginger, nutmeg and cloves in medium bowl; set aside.
Beat together egg whites and egg in a large bowl. Blend in pumpkin, sugars, milk and oil. Add flour mixture, stirring just until combined. Stir in 1/2 cup nuts and mini chocolate chips, if desired.
Spread batter in 9 x 5-inch loaf pan sprayed with cooking spray. Sprinkle top with remaining 1/4 cup nuts.
Bake 55 to 65 minutes, or until toothpick inserted in center comes out clean. NOTE: If using dark nonstick loaf pan, bake at 325°F for 65 to 70 minutes. Allow to cool in pan 5 to 10 minutes. Remove from pan and cool completely on wire rack.