In small bowl, mix topping ingredients until well blended. Set aside. In small mixing bowl, whisk together flour, sugar, baking powder, baking soda, salt and nutmeg. Stir in hazelnuts and set aside. In large mixing bowl, whisk egg until blended. Add vegetable oil, yogurt and orange juice concentrate. Whisk until smooth. Add dry ingredients, all at once, stirring just until flour is evenly moistened. Mix in raisins.

Prepare 1 standard size muffin tin or 3 miniature muffin tins by generously spraying with non-stick spray, or by placing liners in the cups. Divide the batter evenly among the prepared pans, filling each cup a generous 3/4 full. Sprinkle each muffin lightly with the topping mixture. Bake in 400ºF oven for about 18 minutes for the standard sized muffins, or about 12 minutes for the miniature muffins, or until golden. Remove from oven and cool for 5 minutes before removing from tins. Cool on racks. Yield: 12 standard sized or 36 miniature muffins.