Preheat oven to 375° F.
Line a muffin pan with paper muffins cups and lightly coat them with vegetable or canola oil spray.
Streusel Topping: Combine 1/3 cup sugar, 2 Tbsp flour, cinnamon, and butter. Rub the mixture together with your fingers to make coarse crumbs, and set aside.
Batter: In a large bowl combine 2 1/2 cups flour, 1 cup sugar, baking powder, baking soda, salt, allspice. In a separate bowl combine together, buttermilk, milk, ricotta, canola oil, corn syrup, egg, egg whites and vanilla; whisk until smooth. Stir in apple and pour mixture into dry ingredients, mixing just until all ingredients are moist.
Spoon batter into prepared muffin cups, filling 3/4 full; sprinkle the top of each muffin with some of the streusel mixture. Bake for approximately 20 minutes. Muffins should be light golden brown and a cake tester inserted into the center should come out clean. Remove from oven, cool in pan for 10 minutes before removing to cool completely. Store in an airtight container.Servings: 1 dozen muffins