Preheat the oven to 350 degrees F.
In a small bowl, combine the salt, pepper, garlic, fennel fronds and nutmeg and stir well to combine. Place the pork loin in an ovenproof casserole and rub the spice mixture all over the loin. Drizzle the olive oil over the loin. Roast in the oven 1 hour, gradually adding the white wine and basting with the cooking juices.
Meanwhile, bring 6 quarts of water to a boil and add 2 tablespoons salt. Cook the segmented fennel in the boiling water for 5 minutes. Drain the fennel and add to the roasting pan, arranging all around the pork, for the last 20 minutes of cooking time. Allow the meat to rest 10 minutes before carving. Serve with pan juices and fennel.