Lightly grease 18 muffin cups or line with paper liners; set aside. Preheat oven to 190ÂșC . In a large bowl, stir together flour, baking powder, baking soda, salt and sugar. Stir in coconut. Make a well in center; set aside. In a medium bowl beat eggs. Stir in sourdough starter, oil, bananas, orange juice and orange peel. Pour into well in flour mixture. Stir with a fork until dry ingredients are just moistened. Fill prepared muffin cups two third to 0.75 full with batter. Bake in preheated oven 25 to 30 minutes or until golden brown. Remove from muffin cups. Serve hot. Makes 16 to 18 muffins.