Last week, Gaby Scanlon, an eighteen-year-old girl from Lancashire, England, was drinking with friends at a local wine bar when she became suddenly, frighteningly ill. Suffering from stomach pain and unable to breathe, Ms. Scanlon was rushed to the hospital. There, doctors diagnosed her with a perforated stomach. They immediately performed surgery to remove her stomach, saving her life.
The culprit turned out to be a cocktail made with liquid nitrogen – at first glance, a surprising ingredient. At room temperature, nitrogen is a gas, and it is everywhere: it makes up about 78% of Earth’s atmosphere and about 3% of the human body. Nitrogen’s condensation point – the temperature at which it becomes liquid – is an almost inconceivably chilly -196 degrees Celsius (-321 degrees Fahrenheit). Liquid nitrogen can freeze objects instantly without otherwise affecting their composition, and it vaporizes harmlessly into the air in seconds. Liquid nitrogen is often used as a coolant for computers, as a refrigerant for blood and other biological materials, and as a method for removing warts.
Unfortunately, the organs of a living human body do not stand up well to instant freezing. Ms. Scanlon’s doctors have not clarified exactly what happened to her stomach, but there is a likely explanation. Peter Barham, a physicist at the University of Bristol, says that the liquid nitrogen probably burned Ms. Scanlon’s stomach so badly that it burst. A burn from extreme cold, called a cryo-burn, is as serious as a burn from heat. In effect, it is an extremely severe case of frostbite.
Nonetheless, Dr. Barham says, “Liquid nitrogen can be used safely in the preparation of foods” as long as all of the nitrogen has evaporated. This is probably what went wrong with Ms. Scanlon’s drink: the liquid nitrogen used to chill it and crown it with vapor had not evaporated completely before she took a sip.
A cocktail made with liquid nitrogen might sound strange, but a growing culinary movement called molecular gastronomy has been using it for years to make ice cream, drinks, and even savory dishes. The goal of molecular gastronomy is to explore how principles of chemistry and materials science can be used to create foods with unexpected and pleasurable new textures and flavors. Dave Arnold of the French Culinary Institute has developed several techniques for using liquid nitrogen safely in drinks. Earlier this year, he showed The Robb Report how he uses liquid nitrogen to chill champagne flutes. Arnold also flash-freezes herbs with liquid nitrogen before grinding them to a powder and adding them to drinks. In all his recipes, Arnold makes sure that the liquid nitrogen has evaporated before serving drinks to customers.
Liquid nitrogen is far from the only dangerous material used in food and drink. Sharp knives used in food preparation can inflict serious wounds. Spoiled and contaminated food can cause life-threatening illness, and people with allergies must protect themselves against foods that trigger anaphylaxis. In too large a quantity, alcohol is a poison. And extreme heat, like extreme cold, must be handled carefully: a grease fire can be deadly, and a spilled cup of coffee can cause third-degree burns. All of these hazards result in thousands of injuries, but we accept them as risks to be managed.
Nonetheless, Ms. Scanlon’s ordeal raises awareness of the possible dangers of culinary use of liquid nitrogen. The super-cold substance can make a drink look beautiful and produce food textures never imagined before, but it must be handled carefully to prevent injury.