When I ate the sponge at table, I had no idea what to expect. Atop the cloud was the granité, and around it were Creamsicle-orange gooseberry sauce and horseradish cream the consistency of crème fraîche. I was startled by the brisk, cleansing seafood flavor and the soft, foamy texture of the sponge against the fine tingle of the granité and the luxuriant, delicately hot cream. The dish was a triumph of finesse.
Achatz told me that this dish neatly and specifically illustrated the difference between him and Keller. Steaming the shellfish in a broth based on vermouth and aromatic vegetables including fennel, he said, was “straight out of the French Laundry playbook,” as are eight out of ten of the ways he “extracts flavor.” But rather than use the broth for a billi-bi, a creamy French mussel soup, or a tomato-based, saffron-seasoned Provençal stew, he strains the broth and adds Ultra-Tex 3 (a modified tapioca starch that thickens without being heated), whips it into a mousse that looks exactly like mounted egg whites, and then chills it to set like a Bavarian cream. The flavoring accompaniments (with the exception of the fairly extraneous gooseberry) are relatively standard, but the textures are not.
Achatz dates his great leap forward to 2003, when he was cooking at Trio. He decided to check out the convention of the Institute of Food Technology, a group that serves companies like Kraft (the food industry has always loomed large in Chicago: Kraft, Sara Lee, and McDonald’s are all nearby). He and a fellow Trio cook watched, rapt, as someone poured a liquid over a steel tray, sprayed some kind of mist on it, and then encapsulated spoonfuls of it like so many freestanding egg yolks. (At Minibar, in Washington, José Andrés encapsulates the dressing for a deconstructed Caesar salad; the result looks like an egg yolk but spurts dressing when pierced.) The liquid, they learned, had contained sodium alginate, and the mist was of calcium chloride. Achatz took away a one-pound sample of the sodium alginate.
Soon after, he read about a pea ravioli encapsulation in a magazine story about Adrià. It reminded him of his own “truffle explosion”–a truffle broth thickened with old-fashioned gelatin and chilled solid enough to serve as a filling for ravioli. When simmered, the filling melted; it spurted into diners’ mouths. The push to evolve the idea behind the dish (the alginate-calcium combination would be used for all manner of tricks, such as an alarming rush of hot beet juice from an innocent-seeming icy white lemon-thyme foam) was typical Achatz: the discovery and research, the time spent browsing technical websites and speaking with representatives of additive makers unused to customers who want to order in one-pound, not fifty-pound, quantities.
Truffle explosion was a Trio signature, though in his restless way Achatz soon left it behind. My visit to Alinea fell near the anniversary of its opening, a week in which Achatz brought back some of his greatest hits; I asked him to make the ravioli. The effect was interesting enough, but the salty broth and the pasta casing were lukewarm, with cold, hard grated Parmigiano-Reggiano on top. The temperatures didn’t seem intentional, showing that the execution must be flawless for many of Achatz’s effects to come off.