Roasting is a cooking method that utilizes dry heat, whether an open flame, oven, or other heat source. Roasting usually causes caramelization of the surface of the food, which is considered a flavour enhancement. Meats and most root and bulb vegetables can be roasted. Any piece of meat, especially red meat, that has been cooked in this fashion is called a roast. Also, meats and vegetables prepared in this way are described as "roast", e.g., roast chicken or roast squash. Some foods such as coffee and chocolate are always roasted.For roasting the food may be placed on a rack, in a roasting pan or, to ensure even application of heat, may be rotated on a spit or rotisserie. During oven roasting hot air circulates around the meat, cooking all sides evenly. There are several theories for roasting meats correctly: low temperature cooking, high temperature cooking and a combination of both. Each of method is can be suitable under the appropriate circumstances.A low temperature oven (200 to 325 F) is best when cooking with large cuts of meat, turkey and whole chickens. The benefit of slow roasting an item is less moisture loss and a more tender product. At higher temperatures (400 F or more) the water inside the muscle is lost at a high rate.Cooking at high temperatures is beneficial if the cut is small enough (filet mignon, strip loin) to be finished cooking before the juices escape.The combination method uses high heat just at either the beginning or the end of the cooking process, with most of the cooking at a low temperature. This method produces the golden brown texture and crust people desire but maintains more of the moisture than simply cooking at a high temperature, although the product will not be as moist as low temperature cooking the whole time. Searing and then turning down to low the piece of meat is also beneficial when a dark crust and carmelized flavor is desired for the finished product.The objective in any case is to retain as much moisture as possible in the finished product, while providing the texture and color people prefer. During roasting, meats and vegetables are usually basted on the surface with butter, lard or oil to reduce the loss of moisture by evaporation. Recently, plastic oven bags have become popular for roasts. These cut cooking times and reduce the loss of moisture during roasting. They are particularly popular for turkeys.Until the late 19th century, roasting by dry heat in an oven was called baking. Roasting originally meant turning meat or a bird on a spit in front of a fire. It is one of the oldest forms of cooking known.Traditionally recognized roasting methods consist only of baking and cooking over or near an open fire. Grilling is normally not technically a roast, since grilled meat is usually seasoned with wet ingredients or marinated. Smoking differs from roasting because of the lower temperature and controlled smoke application.