Pork loin roast is a lean, slightly less tender cut of pork, and may dry out if cooked for too long or at too high a temperature. Although potentially daunting due to the need to thoroughly cook pork to avoid the parasite Trichinosis, the secret to preparing loin roasts is to take the time for slow cooking with a bit of liquid to keep the meat moist. Cooking pork loin in aluminum foil adds an extra layer of protection to keep it from drying out.
Preheat the oven to 350 F.
Rinse your pork loin roast under cool tap water and blot the excess water off of it with paper towels.
Drizzle a thin stream of olive oil on top of the pork loin roast. Spread it out with your fingers until the entire roast is coated.
Heat a heavy skillet over medium-high heat for 1 minute or so. Place the oiled pork into the hot skillet and brown it on all sides. Let the pork loin gets a deep, dark brown to bring out its rich flavors.
Spread a sheet of heavy-duty aluminum foil lengthwise on a baking sheet. Make sure that there is enough extra to fold over the pork loin roast.
Lay another sheet or two of aluminum foil crosswise over the first.
Place the browned pork loin roast in the center of the aluminum foil. Pour a little bit of white wine over the roast -- a few tablespoons to ¼ cup should be enough, depending on the size of the roast.
Season the roast with garlic salt, lemon pepper and rosemary to taste. Rub the rosemary between your palms to release its fragrant oils before sprinkling it over the roast.
Fold the aluminum foil over the sides of the roast and fold them together. Repeat with the ends, making sure that the foil is sealed tightly.
Poke a leave-in meat thermometer through the foil and into the thickest part of the pork loin.
Braise the pork loin for 20 to 30 minutes per pound, or until the meat thermometer reads at least 145 F, or higher if you like your pork cooked medium or medium-well.
Let the pork roast rest for at least 4 minutes before unwrapping and slicing it.