Cooking the meat to an internal temperature
of at least 137 degrees F will kill any trichinae present. You can also kill it by freezing the meat at a temperature below minus 10 degrees F for several weeks, but freezing alters the meat's cellular structure, making it mushy when cooked.
Intelligent safeguarding is not the same as overreacting, which is what many cookbooks are doing when they recommend cooking pork to a temperature between 170 and 185 degrees F. If you follow those directions, your meat is bound to be less palatable and nutritious, and furthermore, prolonged cooking causes dryness, toughness, and excess shrinkage owing to moisture loss and coagulating proteins.
You can tell whether pork has been overcooked with the knife-and-fork test. If the meat does not cut easily, it's overcooked. The other side of the coin is that you don't want to cook your pork to just 137 degrees F because the meat's flavor would not develop fully. For pork that is both rewarding and safe to eat, it is recommended to be cooked to an internal temperature of 150 degrees F, with a 13 degrees F of safety margin. The center of a pork roast will be slightly pink. Use a cooking thermometer
to determine the cooking temperature