Hamburger such as , due to the occasional initial improper preparation of the meat, so caution is needed during handling and cooking. Because of the potential for food-borne illness, the USDA recommends hamburgers be cooked to an internal temperature of . If cooked to this temperature, they are considered well-done. Burgers can also be made with patties made from ingredients other than beef. For example, a "turkey burger" uses ground turkey meat, a "chicken burger" uses ground chicken meat. A "buffalo burger" uses ground meat from a bison, and an "ostrich burger" is made from ground seasoned ostrich meat. A deer
Hamburger eaten by many emigrants on their way to America, but may have contained roasted beefsteak rather than Frikadeller. Hamburg steak is reported to have been served between two pieces of bread on the Hamburg America Line, which began operations in 1847. Each of these may mark the invention of the Hamburger, and explain the name. There is a reference to a "Hamburg steak" as early as 1884 in the Boston Journal. On July 5, 1896, the "Chicago Daily Tribune" made a highly specific claim regarding a "hamburger sandwich" in an article about a "Sandwich Car": "A distinguished favorite, only five