Sift together flour, baking powder, salt and spices. Stir in apple, brown sugar and nuts. In a separate bowl, combine eggs, juice and butter. Stir into apple mixture just until blended. Fold in bran flakes. Pour into oiled muffin pans, filling each cup about 2/3 full. Bake at 400 degrees for 15-20 minutes. Makes 12 muffins