"A frozen turkey won't drip juices around the kitchen that could cause sickness and will come out of the oven juicy and full of flavor," Iowa State University said in a statement. "It's critical that the final temperature of the deep portions of the turkey reach at least 165 degrees F to prevent foodborne illness. The National Turkey Federation recommends that the temperature reach 175 degrees to 180 degrees F in the leg/thigh portion."
To roast a 12-15 pound frozen turkey:
-- Preheat oven to 325 degrees F, making sure that the pan will fit on the middle shelf of the oven.
-- Line the baking pan with foil and place the rack in the pan.
-- On a clean surface, unwrap the frozen turkey and place it on the rack.
-- At 3 hours: If turkey is defrosted, giblet packages can be removed with tongs and/or forks. Giblets packaged in plastic should be removed and cooked separately; if the plastic bag has melted or been altered, do not consume the giblets. Giblets packaged in paper can be removed and cooked separately, or cooked completely in the bird making sure they reach 165 degrees F.
-- Butterball's Turkey Talk-line said the bag is designed to go through the roasting process and it can be kept inside the turkey.
-- At 4 to 5 hours: Measure temperature at deepest point in the breast. Minimum temperature: 165 degrees F. Keep roasting if it's not 165 degrees F. Plan on 5 to 5.5 hours for a 12-14 pound turkey.
-- When done, remove from oven and place a foil tent over turkey. Wait 20 to 30 minutes before carving.
-- Refrigerate leftovers within 2 hours.
Traditional instructions recommended cooking poultry to 180 degrees F until U.S. Department of Agriculture tests showed 165 degrees was sufficient, but the Turkey Federation continues to recommend 180 degrees because this ensures the meat is no longer pink yet will remain juicy.