Preheat oven to 350 degrees F. In a small saucepan or frying pan, saute leek and garlic with olive oil until brown and wilted. Combine tomato sauce, wine, meat stock, basil, oregano, flour, and salt in the same saucepan. Bring to a boil. Reduce heat to low and simmer uncovered for 15 minutes. Set sauce aside.
Combine ground turkey, egg substitute or eggs, zucchini, and 1/4 cup of the prepared sauce in a large bowl. Mix well. Add flour if needed. Pat into a 4 x 8-inch loaf pan, lined with baking paper (do not fill all the way). Bake for 45 minutes. Discard any drippings. Pour 1/2 cup of the remaining prepared sauce over the top of the loaf and bake for an additional 15 minutes.