“For safety, the USDA recommends cooking lamb patties and ground lamb mixtures such as meat loaf to a safe minimum internal temperature of 160 °F as measured on a food thermometer. However, whole muscle meats such as roasts, steaks, and chops may be cooked to 145 °F (medium rare), 160 °F (medium), or 170 °F (well done).For safety, the USDA recommends cooking lamb patties and ground lamb mixtures such as meat loaf to a safe minimum internal temperature of 160 °F as measured on a food thermometer. However, whole muscle meats such as roasts, steaks, and chops may be cooked to 145 °F (medium rare), 160 °F (medium), or 170 °F (well done).