Using a mortar and pestle crush rosemary, fennel seeds, nutmeg and white pepper until combined. Add crushed garlic, olive oil and white wine and continue to mix until you have a runny paste.
Meanwhile lay the butterflied pork loin, fat side down, on a clean dry surface. using a pastry brush evenly cover the pork with the paste until all is gone. Gently roll up pork loin and tie from the middle of the loin first. After the first tie, continue tying to the edges every inch until the loin is tied completely. Using your hands rub in any excess paste that had dripped out into the scored fat and season all over with salt. Stand the piece of pork on a wire rack and cook in the oven for approx. 40 minutes.
A good way to test the pork is to skewer the meat, if liquid runs clear it is cooked. Be careful not to over cook the pork, you want the loin to be nice and pink. Wrap with foil and rest pork in a warm place for 20 mins. Slice and serve.