« February 2012 Table of Contents
Top Story: Take a bath
Sous vide, Cvap manufacturers bide time with education, wait for QSR, casual-dining adoption
By Steve Coomes
February 05, 2012
For years the phrase “low and slow” was heard mostly around barbecue fires, where pit masters cooked meat for hours at low temperatures to preserve moisture, impart delicate smoke and render fat. More commonly, however, fine-dining chefs are applying the same technique to seafood cooking, though without hardwoods and smoke. Increasingly, the tools of their trade include equipment designed to cook seafood in high-moisture environments and at temperatures so restrained that diners sometimes wonder if their food is even fully cooked.
Though not particularly high tech, these machines cook with such precision that seafood prepared using them can be maintained at a desired temperature for hours — without overcooking. In such a state, a portion of seafood could be retrieved the moment it’s ordered at a restaurant and finished quickly with flash-grilling, broiling or searing before plating.
“It’s kind of backward compared to how we all were taught to cook traditionally,” says Barry Yates, director of innovation at Winston Industries, a Louisville, Ky., manufacturer of Cvap. The name is short for controlled vapor, describing the high-humidity method of cooking and holding food in a sealed, temperature-controlled cabinet. Originally designed in the early 1980s for fast-food providers wanting to hold food at serving temperatures after cooking, Winston engineers and chefs realized Cvap could cook proteins slowly and precisely to yield unusually tender and juicy results that were cooked evenly throughout.
Yates, a fine-dining chef in the 1980s, had to rethink much of what he’d learned when he joined Winston in 1991 as a research chef. Slow-cook technologies such as Cvap and sous vide ran counter to his experience.
“In restaurants, we were supposed to cook a piece of fish to proper doneness on a grill or in a sauté pan or oven, and then have it come out aesthetically beautiful,” Yates says. “Not only does that take a high level of skill, you’ve got to be able to do it right all night, and night after night.
“When you’re using water vapor, or a water bath like in sous vide, it’s perfectly cooked and holding, and then all you’re doing is working on the finished aesthetic when it’s ordered. That removes a good deal of the skill from cooking, but it provides such a level of precision that the finished product is better.”
Sous vide also utilizes the low-and-slow method by sealing raw food under vacuum (the literal meaning of “sous vide”) in plastic pouches, and then cooking them in a low-temperature water bath for extended periods. As happens within the controlled-vapor environment, protein collagens (which form connective tissue and other fibrous components in flesh) break down and nearly dissolve at temperatures below the point at which muscle begins to cook. As with Cvap, the result is evenly cooked and incredibly moist.
Though Cvap and sous vide aren’t new technologies (sous vide was first used in restaurants in the 1970s), their application still is viewed as revolutionary to classically trained cooks, Yates says.
“We call this style of cooking reverse staging because we get the food to a specific temperature and doneness and then do the aesthetic (heating) at the end,” Yates began. “When I cooked for a living, no one ever knew there was an option, that you could do it kind of the opposite way. We’re teaching people now that you don’t have to cook and caramelize at the same time.”
Good, but not perfect
U.S. chefs using sous vide and Cvap say both tools are handy in modern kitchens, but warn that each has its limitations. Barton Seaver, who, before becoming a speaker and author, was executive chef at such tony Washington, D.C., spots as Café Saint-Ex, Bar Pilar and Hook, avoids sous vide because he believes the vacuum pressure placed on fish during sealing compromises the flesh.
“Compressing a piece of fish in plastic damages its cell walls, which isn’t a whole lot different than ripping it apart instead of cutting it properly,” says Seaver, who was honored in 2007 by the Blue Ocean Institute for his commitment to oceanic sustainability. “That’s also a lot of energy being used to make the plastic, seal it, cook it, put that plastic in the trash and haul it off somewhere.”
Delicate fish species like flounder and trout don’t do well in Cvap, says Dean Corbett, chef-owner of Corbett’s: An American Place, in Louisville, Ky.
“I won’t put cod or sole in there because when they come up to temp, they fall apart,” says Corbett, who’s used Cvap for 15 years. But shellfish, he adds, are another matter. “I cook lobster tails in lobster stock in the Cvap at 95 degrees and just go super slow. It comes out so tender, it’s unreal.”
Marc Collins, chef and co-owner of Circa 1886 in Charleston, S.C., agrees that delicate fish can be damaged under vacuum, so he chooses fattier and thicker species, such as salmon. He also believes the airtight environment of a sous vide pouch helps drive flavors into the flesh as it cooks.
“I like to put some herbs in the bag with the fish and a pat of butter to make a poaching liquid,” he says. He places each sous vide pouch in an immersion circulator that moves both the heated water and pouches around the tank to ensure temperature uniformity. “You can use it to cook salmon to a perfect medium and hold it there. Even the color stays.”
Acknowledging that each cooking technique works better in some situations than others, Wylie Dufresne, famed molecular-gastro chef at New York’s WD-50, uses both sous vide and Cvap — sometimes on the same fish dish.
“We’ve taken cuttlefish and cooked it sous vide and then finished it in the Cvap out of the bag,” says Dufresne. “But I honestly don’t think one’s better than the other. It just depends on the fish and the application. We might be after a different texture or doneness in a fish and choose one over the other. During service, we have two (sous vide) water baths and a Cvap going at the same time to maximize our options.”
Seaver says that fish harvested during certain times of the year don’t benefit from Cvap cooking.
“When the first catches of the pompano season are coming in, a time when it’s feeding on sand eels, it’ll have stronger metallic taste that’s drawn out in slow cooking,” he says. “But when they’re eating inshore fish and getting plump and fat, the Cvap is a good solution. You have to understand what qualities your cooking method will amplify and figure if you want those qualities amplified.”
Best practices key
Sous vide cooking has faced safety criticism in the past, but nearly always due to users not following best practices. It was banned temporarily several years ago in New York City when health department officials found instances of improper storage of food sealed sous vide. According to Christoph Milz, sales and marketing manager for PolyScience, a sous vide equipment manufacturer in Niles, Ill., some chefs and butchers in the city assumed the vacuum seal made the food shelf stable.
“If you leave sealed food at room temperature, anaerobic bacteria such as salmonella and E. coli will thrive in that environment,” says Milz. “With sous vide, you handle food exactly the same way you do without it. Either the sealed package goes into a refrigerator or the water bath, or, if cooked, it goes into an ice bath or is served immediately.”
Appearance and doneness also give rise to some concerns with both methods. Since some species are safely pasteurized at less than 120 degrees-F when cooked sous vide or in Cvap, their finished appearance looks “rare” — results chefs using those techniques actually want to achieve.
However, people used to seeing fish cooked to a uniform opacity aren’t always comfortable with that look, says Michael Cimarusti, executive chef and co-owner of Providence LA in Los Angeles. When he serves halibut cooked sous vide, “the fish looks barely cooked but flakes like perfectly cooked fish,” he says. “On some fish we’ll cook it to 118 (degrees), which is cooked, but looks almost raw. It has this beautiful translucence that throws some people off. So we have to talk to our guests about that and explain what we’re doing.”
Milz says that while such finished seafoods may appear raw, when strict time and temperature standards are met, it’s fully pasteurized. “If I cook egg at 134 Fahrenheit, it’s not considered safe. But if I cook it for 2 hours at 134, then it’s pasteurized and is safe. Same for seafood: It’s a function of time and temperature, not one or the other, and that’s what chefs and health inspectors have to understand.”
To add color and warmth to fish cooked sous vide or in Cvap, Cimarusti sometimes heats it under a broiler briefly before plating it for a guest. But even then, it’s not bubbling on the plate when it arrives at the table. “Cooks are supposed to have tough hands anyway,” he begins, “but we say if the stainless steel tray we use for the broiler is too hot to hold in hand, you’ve overcooked it.”
Seaver agrees with peers who insist on retaining the remarkable textures delivered by sous vide and Cvap, saying neither is worth the investment if all a chef wants to do is cook food until it’s well done and bereft of natural color.
“I’m a big fan of slow, meticulous, purposeful heat, and cooking things like sablefish in the Cvap at 140 degrees at 100 percent humidity is beyond compare,” he says. “It comes out of there as tender as panna cotta, and halibut done that way is just buttery. So why would you want to change that texture, especially when it’s so easy to do?”
Decades after Cvap’s creation and with many thousands of units sold, Yates says only a small percentage of fine-dining restaurants use the cabinet as a cooking device rather than a holding box. High-end chefs using it to cook have specific results that chefs in casual or fast-food segments aren’t after. Milz believes the same holds true for sous vide.
“In fast food you don’t see the same desire to maintain product integrity, so no, I don’t see an application,” Milz says. “But in casual dining, I do.”
Milz and Yates believe both technologies will be used increasingly in fast-food and casual dining as corporate chefs better understand them. High-volume casual restaurants can receive factory produced, par-cooked pieces of seafood stored sous vide, refrigerated and shipped by the case. Kitchen staffs would start the shift with a few portions of the fish in the water bath and when ordered, they’ll be ready for finishing with a garnish or sauce.
And as Yates says, Cvap’s original use as a holding cabinet for fried chicken works just as well for fried seafood in a QSR or casual environment.
“There’s great potential for that application, but too few people know about it,” says Yates, adding that Cvap is already in use in three fast-casual chains that use it to hold par-cooked fish for tacos. “To have something that will hold a cooked product at that finished temperature without overcooking it is perfect for that environment. But the truth is much of our growth will come from education over time.”
Contributing Editor Steve Coomes lives in Louisville, Ky.