Cool Food

Fans of the popular cooking method sous vide tout the flavors and tenderness it provides, but some people worry about the method’s safety. (Erikoinentunnus via Wikimedia Commons)

Fans of the popular cooking method sous vide tout the flavors and tenderness it provides, but some people worry about the method’s safety. (Erikoinentunnus via Wikimedia Commons)

Like many chefs, John Placko is a huge fan of the cooking technique called sous vide. At the restaurants where he has worked and the culinary academy where he teaches cutting-edge “molecular cuisine,” foods cooked sous vide are an essential part of the menu.

“There’s so many benefits, particularly if you’re cooking, say, ribs,” says Placko, an Australian who lives and works in Toronto. “You would cook ribs for 48 hours and get an incredible, tender product, where the fat content in the meat and the connective tissue tend to dissolve and become gelatinous, releasing the flavor into the meat.”

Sous vide, which means “under vacuum” in French, typically involves vacuum-sealing a cut of meat or other food in plastic and submersing the package in a warm-water bath kept at a precisely controlled temperature, often for hours. The food is cooked evenly all the way through, the juices are preserved, and diners are ecstatic.

“You end up with ribs where the bone will basically just slide out completely clean, so people that have eaten those ribs never want to eat another kind of rib after that,” Placko says.

The popularity of sous vide has exploded in the past few years, spreading the delights of perfectly cooked meat and other foods to gastropubs and home kitchens. But that growth has also occasioned some consternation among regulators who worry that misuse of low-temperature cooking and vacuum storage could end up sickening some of the cooks who have eagerly adopted the method, not to mention their dinner guests or customers.

“It is a technique that does require attention, and you do have to understand that you’re dealing with people’s health,” Placko says. “You don’t want to have any kind of food-poisoning incident.”

Refining an Ancient Technology

The roots of sous vide cooking reach far back in history to traditional practices of wrapping food in leaves or animal bladders before cooking. Maori people in New Zealand used a very similar technique, lowering flaxen bags of food into naturally occurring hot springs and leaving them to cook slowly.

In the West the discovery of slow cooking at low temperatures is often credited to Benjamin Thompson, known as Count Rumford, whose wide range of interests included the study of heat and cooking. In one experiment conducted at the end of the 18th century, he tried to cook a shoulder of mutton in a machine he’d invented to dry potatoes with hot air. He gave up after three hours, feeling “rather out of humour at my ill success”; but the mutton remained in the apparatus until the next morning, when the maids found it perfectly cooked.

“It was neither boiled, nor roasted, nor baked,” Rumford wrote. “The gentle heat to which it had for so long a time been exposed, had by degrees loosened the cohesion of its fibres, and concocted its juices.”

An irony of today’s worries over sous vide safety is that vacuum-packing has always been used to prevent food spoilage. In 1900, Hills Bros. began selling coffee in vacuum-sealed cans to preserve the taste, and by the 1930s early efforts were under way to vacuum-pack raw meat in latex or other polymers.

In the 1960s researchers began cooking food sealed in plastic, according to Modernist Cuisine, an encyclopedic food-science guide and cookbook written by sous vide enthusiast and former Microsoft executive Nathan Myhrvold. During that time Swedish hospitals developed a system of vacuum-sealing cooked food, boiling it for a few minutes more, and delivering the packages to facilities around Stockholm.

True sous vide was created when hospitals in South Carolina and plastic-film manufacturer Cryovac collaborated to make the key innovation of vacuum-sealing raw ingredients before cooking. The process was refined by French experts, particularly chef George Pralus, who used sous vide in the early 1970s to minimize shrinkage of foie gras, and food scientist Bruno Goussault, who developed temperature guidelines and techniques that allowed commercial adoption. Their work dovetailed with a nascent movement to bring food science and chemistry into restaurants and home kitchens in order to create new dishes that ranged from sous vide steaks to nitrogen-chilled ice cream and even fruit-juice caviar.

An early proponent of sous vide was Nicholas Kurti, a Hungarian physicist at Oxford University who had created temperatures near absolute zero in his lab. During a 1969 talk at the Royal Society he reproduced Rumford’s slow-cooking experiment and made an “inverted Baked Alaska” pie—with a cold crust and a hot filling—using the newly invented microwave oven.

“I think it is a sad reflection on our civilization that while we can and do measure the temperature in the atmosphere of Venus, we do not know what goes on inside our soufflés,” he told the audience.