Roasting is a cooking method that uses dry heat, whether an open flame, oven, or other heat source. Roasting usually causes caramelization or Maillard browning 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 method can be suitable under the appropriate circumstances. The objective in any case is to retain as much moisture as possible, while providing the texture and color people prefer. During roasting, meats and vegetables are frequently 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, but reduce flavor development from Maillard browning. They are particularly popular for turkeys.