Chefs have found less lofty ways to employ the technique as well. At CityZen, in the Mandarin Oriental hotel in Washington, they make ice cream bases in sous vide. "There's no putting your sugar and egg and cream in a pan and stirring," says Eric Ziebold, the chef. His pastry chef blends the ingredients, seals them in a bag and cooks it in water.

"More than anything, the vegetables and the proteins taste remarkably more like themselves," Dan Barber, the chef and owner of Blue Hill, wrote in an e-mail message. "When it comes to things like artichokes, steaming and boiling and braising are fine, but there's a great loss of liquid as it cooks -- which is another way of saying a great loss of flavor because the juice of the artichoke itself, while mostly water, is very flavorful. Sous vide eliminates this loss, and hence the sensation that you're tasting a true artichoke -- not just a delicious artichoke, but an artichoke the way it was intended to taste."

Much is made of the artistry of chefs, but running a restaurant kitchen well often has more to do with control and consistency. And in large kitchens or multiple restaurants, those things can get out of hand pretty quickly. Alléno, the chef at Le Meurice, oversees 72 cooks; Daniel Boulud has a staff of 65 to 70 among his three New York restaurants. Most cooking relies on the cook's ability to judge doneness based on sight and feel. With sous vide, it is all about precise times and temperatures. "You can have your restaurant 6,000 miles away," Ziebold says, "and you don't have to worry about the cooks at your restaurant in D.C. getting the duck right because they're cooking it sous vide and they know the temperature." Every year, Janos Kiss, the corporate executive chef for Hyatt Hotels and Resorts, prepares a dinner for more than 5,000 people on Super Bowl weekend. It used to take 20 chefs four days to cook the dinner. Now, with sous vide, they do it with six chefs in two days.

In the long run, sous vide's great contribution may well be this consistency. A chef with a restaurant empire, like Nobuyuki Matsuhisa, may finally be able to guarantee that the lobster with wasabi-pepper sauce at Nobu in London is every bit as good as the one at Nobu in New York. It may spell the end to bad wedding food. And if it catches on at companies from Stouffer's to Whole Foods, it could forever alter the state of convenience food.

In the meantime, all the attention being paid to temperature and laboratory precision has pushed chefs in more creative directions. When Grant Achatz built his new restaurant Alinea in Chicago, thermal circulators from PolyScience, a laboratory-equipment manufacturer, were part of the kitchen design. To these, he has added a 40,000-r.p.m. homogenizer (what Philip Preston, the president of PolyScience, calls a "coffee grinder on steroids") -- for making the world's most emulsified vinaigrettes and confections like carrot pudding made with carrot juice, cocoa butter and grapeseed oil -- and an entirely new mechanism they're calling the Antigriddle, which has a surface that chills to minus 30 degrees Celsius (minus 22 Fahrenheit), allowing you to freeze food in the same way you would sauté it. A dollop of sour cream becomes brittle on the bottom and stays at room temperature on top.

For all chefs' forward thinking, though, top kitchens still run on frat-house principles. So sous vide also comes in handy for hazing new cooks. At WD-50, Dufresne said, "I've seen virtually every kind of personal belonging end up in one of these bags." Veteran cooks are known to take a new cook's clothing from his locker and put it through the sous vide machine, compressing his jeans and shirt to the size of hockey pucks. In late July, Goussault went to Citronelle in Washington for a follow-up training session with Michel Richard's head cooks, David Deshaies and Cedric Maupillier. They were having trouble with the salmon and sweetbreads done sous vide. The salmon had a perfect silky texture but was too fragile and, they worried, undercooked. And the sweetbreads were losing too much liquid.

Goussault is often called in to help chefs perfect their technique. "My job is to repeat, repeat, repeat," he says. He unpacked his briefcase, removing a laptop, a box of batteries, a jumble of wires and a number of handheld monitors that, when hooked up to the foods with probes, can record their minute-to-minute temperature arc during the cooking process. The large stoves around the kitchen were mostly unoccupied. Two thermal circulators sat poised on a steel countertop, humming like Jacuzzis. Deshaies dropped two pieces of salmon in ice water that contained 10 percent salt, then set a timer for 10 minutes. Salt, according to Goussault, "modifies the osmotic pressure in the cells," meaning it prevents the albumen, that white substance, ghastly to chefs, that gathers on the surface of fish, from leaching out of the salmon when it cooks. They sealed the salmon in sous vide and inserted probes. It now looked as if the salmon had a heart monitor.