While the minimum safe internal temperature for pork is 145 degrees F, I've found it best to cook pork loin roast to an internal temperature of 150 degrees F. to no more than 155 degrees F. If you pull the roast out of the oven when it's in this range, it should be perfectly cooked with just a tiny hint of pink in the center of the thickest portion. The total roasting time can range from 20 to 25 minutes per pound. Pork loin is a lean cut that can dry out if overcooked so be vigilant and check the temperature with an instant read meat thermometer. Allow the pork to rest for 15 minutes before slicing and serving.