When ready to roast, heat the oven to 350 F. Fit a roasting pan with a rack.
Remove the turkey from the brine and discard the brine. Pat the turkey dry with paper towels, then set it onto the roasting rack. Roast for 2 to 2 1/2 hours, or until the temperature of the breast reaches 160 F and the thighs reach 170 F. If the turkey begins to darken too much, over it loosely with foil.
Transfer the turkey to a serving platter, wrap with foil, then set a couple layer of bath towels over it to keep it warm.
Remove the rack from the roasting pan. Place the roasting pan over medium heat on the stovetop (you may need two burners) and bring the juices to a simmer. Add the wine and scrape up any browned bits on the bottom of the pan. Pour the broth into the pan, whisking continuously. Then add the flour and whisk to combine. Simmer for 5 minutes, while continuing to stir. Season with sage, salt and black pepper.
Nutrition information per serving: 420 calories; 170 calories from fat (40 percent of total calories); 19 g fat (5 g saturated; 0 g trans fats); 185 mg cholesterol; 4 g carbohydrate; 0 g fiber; 2 g sugar; 56 g protein; 480 mg sodium.