Liquid nitrogen: handle with care

Cocktails flash-frozen using liquid nitrogen may be new (and dangerous), but chefs have been using the chemical for years much more safely
A chef cooking with liquid nitrogen


Liquid nitrogen was once just an obscure chemical used in a completely different context by high-end chefs such as Ferran Adrià and Heston Blumenthal. They used it to flash-freeze food – a technique now mimicked in restaurants across the UK.

Should we be worried? Not if you're in a restaurant, says Colin McGurran, chef proprietor of Winteringham Fields, Lincolnshire. "When liquid nitrogen is used to make cocktails, it remains as an active ingredient," says McGurran. "But in a kitchen, we just use it as a cooling mechanism."

Nitrogen boils at -196C – so once it is released from its container, it turns immediately into a vapour, before disappearing completely. The vapour is extremely cold: when sprayed on food, the food freezes in an instant. One chef, Spaniard Dani Garcia, uses it to create icy balls of frozen oil. Others, such as McGurran, like to make ice-cream or sorbet: the flash-freezing creates smaller, smoother ice crystals. "It simply helps the sorbet cool down quickly – faster than it would in a freezer," says McGurran. "Ice crystals don't get to set, so the sorbet tastes more like a smooth puree."

In this context, liquid nitrogen is still dangerous – it can be too cold to touch – while one German amateur lost his hand in an explosion. But because the chemical is used as a tool rather than an ingredient, diners themselves don't have much to worry about.

That's not necessarily the case in some bars. It's not yet known what kind of cocktail Scanlon drank, but McGurran advises against drinking anything mixed with liquid nitrogen or containing nitrogen ice-cubes. The icy liquid might corrode your insides directly – or start to boil, expand rapidly, and then put too much pressure on your stomach.

As for Scanlon, happily she has survived – probably with her oesophagus sewn directly to her intestine. She can still eat normally, just in smaller portions. "Maybe 'stay off the liquid nitrogen' is not a fucking funny thing to say to me," she tweeted. "I nearly died."

This article was amended on 9 October 2012. The original said that a German amateur lost his hand after lighting liquid nitrogen by mistake. Liquid nitrogen is not flammable.