Preheat oven at 350. Prepare a 9 "x 5 " loaf pan with cooking spray and flour; set aside. In a mixing bowl, combine flour, brown sugar, baking powder, cinnamon, nutmeg, baking soda, ginger, and cloves. In another mixing bowl, combine pumpkin, milk, egg whites, raisins, and sour cream. Mix dry ingredients with wet ingredients just until moistened. Pour batter into prepared pan. Bake one hour.