In a large bowl, combine the ground turkey, shredded apple, breadcrumbs, Parmesan, egg, sage, parsley, garlic, onion powder, salt, pepper, and nutmeg. Mix gently—avoid overmixing.
1 pound ground turkey, ½ cup breadcrumbs, ¼ cup grated Parmesan cheese, 1 large egg, 2 tablespoons fresh sage, 1 tablespoon fresh parsley, 2 cloves garlic, ½ teaspoon onion powder, ½ teaspoon salt, ¼ teaspoon black pepper, ¼ tsp ground nutmeg