Boiling

Boiling cooks food by immersing it in water or another water-based liquid, such as stock or milk, that has been heated to its boiling point, the temperature at which the liquid's vapor pressure equals the surrounding atmospheric pressure and rapid conversion from liquid to gas occurs; for water at sea level this is 100 degrees Celsius, though the boiling point drops at higher altitudes as atmospheric pressure falls. Several related cooking techniques sit at different points along the same heat scale, including simmering, a gentler form of boiling, along with blanching, steaming and poaching. Boiling water is also used outside cooking to make water safe to drink, since holding it at 100 degrees Celsius for one minute inactivates most microorganisms and viruses.