Cooking Under Pressure
WHY YOU SHOULD CARE
Even on the cheap, sous vide makes for some rich results.
Sea urchin foam and ectoplasmic olives will never make it into most home kitchens, but the most radical technique in the molecular-gastronomic bag of tricks is at last within reach. It’s sous vide, the slow-and-low method of water cooking that makes foodies swoon and radically improves the taste and texture of everything from foie gras to carrots. Sous vide is basically a warm bath. No nitrogen oxide required.
No big outlays anymore, either. Until recently, sous-viding required purchase of a high-tech tank, produced by a manufacturer of laboratory equipment, and a vacuum sealer — essentially a $1,000 mini Jacuzzi. You also had to surrender abundant counter space. But a new, ingenious design now makes sous vide bliss portable and almost affordable at just under $200 — mine is an elegant, bottle-sized number made by Sansaire. When you want to sous vide something, you fill a pot (your own) with water, immerse the Sansaire, attach it to the pot and set the temperature to within a fraction of a degree. The device will keep it exactly there, gently pumping the water past its heating coil, for as many hours or days as this very gentle technique requires to transform tough cuts of meat or drab vegetables into divine incarnations.
After some fumbling and cursing, I have solved the Great Zip-Close Bag Mystery.
Why doesn’t the food turn watery and tasteless? Because you put it in a plastic bag and force out the air before slipping it into the water. This is how sous vide got its name — “under vacuum” — in the French restaurant kitchen where it was perfected. In the dawn of the sous vide age, chefs used vacuum-bagging machines to create true vacuums in sealed bags so that water couldn’t touch the food and air in the bag wouldn’t interfere with the transfer of heat to the food from the water bath.
Then some unjustly obscure genius realized that the home cook could dispense with the vacuum-bagger and substitute zip-closing bags sold for pennies in supermarkets, letting gravity push out the air: That’s the Archimedes Principle, as channeled by some particularly enthusiastic gastrobloggers. Theoretically, Sous Vide a la Zip-Close Bag works like this: For classic Anjou carrots, you put your sliced carrots, plus some water, butter and sugar in the zip-close bag. Then close the bag almost all the way, lower it into the water and let the weight of the water force out the air on the way down. Zip the top, clip to the pot’s lip and spend the next 40 minutes reading OZY while the sous vide machine, set to 185 degrees F, does its thing. Then dump the contents of the bag into a skillet and toss the carrots in the cooking liquid until it reduces to a golden glaze. The carrots will be tender but will have retained a depth of flavor that conventional boiling and sautéing would largely eliminate.
But it didn’t work that way for me. The zip-close bags all leaked at the seams after a few minutes of immersion. Water seeped in, and food particles contaminated the water bath. All my projects were ruined by water infiltration. None of the authorities I consulted had mentioned this risk or how to avoid it. After watching me stomp, curse and fumble, my wife suggested I try some very large zip-closing freezer bags she kept in the cellar. Evidently, these gallon bags are made of a thicker, more heat-resistant plastic. They did not leak.
I had solved the Great Zip-Close Bag Mystery.
The raw salmon turned out insipid, compared to the profoundly salmony sous-vided pieces.
And so I progressed to salmon, using a recipe adapted from directions published online. The fish cooked for 35 minutes at 109 degrees — exactly 109 degrees. I seared it in butter afterwards, along with some pieces of raw salmon from the same filet. The raw salmon turned out insipid, compared to the profoundly salmony sous-vided pieces. It was as if I was getting the natural flavor of raw salmon sashimi with a tender, cooked texture that was uniform from one edge of the fish to the other.
Sous vide aficionados will tell you they get the same effect with steaks, medium rare wall-to-wall. And people willing to keep their machines pumping away for many hours report that rough cuts of meat like short ribs or bottom round emerge as tender as filet mignon but without being turned to mush or losing their spirited taste. I have enjoyed such sous-vided meat in restaurants and look forward to creating the same alchemical results at home.
Now all I need is a practical sous vide cookbook. Except for star chef Thomas Keller’s brilliant but very intricate Under Pressure: Cooking Sous Vide, the available titles haven’t made me want to put them in my Amazon shopping cart. Let us hope that some millennial Julia Child is even now at work on Mastering the Art of Sous Vide Cooking.