Toast is a form of bread that has been browned by exposure to radiant heat. This browning is the result of a Maillard reaction altering the flavor of the bread and making it firmer so that it is easier to spread toppings on it. Toasting is a common method of making stale bread more palatable. Bread is often toasted using a toaster, but toaster ovens are also used. Though many types of bread can be toasted the most commonly used is “sliced bread”, referring to bread that is already sliced and bagged upon purchase and may be white, brown, or multigrain.
Toast is commonly eaten with butter or margarine, and sweetened toppings, such as jam or jelly. Regionally, savoury spreads, such as peanut butter or yeast extracts, may also be popular. When buttered, toast may also be served as an accompaniment to savoury dishes, especially soups or stews, or topped with heartier ingredients like eggs or baked beans as a light meal. Toast is a common breakfast food. While slices of bread are most common, bagels and English muffins are also toasted. Scientific studies in the early 2000s found that toast may contain carcinogens caused by the browning process.[