The Gastronomer: A miracle of molecules

By Andreas Viestad
Special to The Washington Post
Wednesday, March 31, 2010

The first thing you should think about if you are inventing a sauce is the name. If your invention stands the test of time, taking its place among the world's great sauces, the name ideally will stick with it. That is why Hervé This, the father of molecular gastronomy, named his invention Sauce Kientzheim, after the small village in Alsace that his family hails from.

The name doesn't exactly roll off the tongue, a la hollandaise, but Kientzheim "is the most beautiful place in the world, and the only name I found worthy of my sauce," says This.

I first came across the sauce at Pierre Gagnaire's eponymous three-Michelin-starred restaurant in Paris. It stood out, even as I was bombarded by experimental dishes and wild flavors. It felt familiar, but in an uncanny way, as if I were tasting something I had previously encountered only in a dream. It had many of the same properties as hollandaise and bearnaise, but with a thicker, firmer consistency and a rich flavor, with hints of caramel. It accompanied a simple piece of sole, which by itself tasted of very little. With the sauce, though, it was a rendition of the classic sole meuniere that was at once true to the original and a revelation.

One of the aims of This's research has been to analyze recipes. When he and the British-Hungarian scientist Nicolas Kurti coined the term "molecular gastronomy" in the late 1980s, they lambasted the lack of basic knowledge about the things we eat and cook, famously summed up in Kurti's aphorism that "We know more about the temperature in the atmosphere of Venus than we know about what goes on inside our souffles." (Kurti later became the first person to measure the temperature in a souffle, while This measured the pressure.)

But This doesn't stop there. He also wants to construct new recipes. The saying goes that necessity is the mother of invention, but that's not really the case most of the time, and certainly not with This. Instead, knowledge of how the world works enables him to think of new ways to maneuver around it, necessary or not.

In cooking, emulsion sauces are where craft meets alchemy. An emulsion is an impossibility, a combination of liquids that are unblendable: fat and water, the first in the form of oil or butter, the latter from the egg and in the form of wine, lemon juice, vinegar or the like. We may know how to make these emulsion sauces -- and with a bit of practice we might even approach them without much fear -- but very few of us know what goes on, how we make water and fat interact and become one. So we wisely stick to the rules.

Most of us haven't reflected on the difference between a mayonnaise and a hollandaise, apart from what the recipe tells us: Mayonnaise is made by gradually whisking oil into an egg yolk until the result is a thick, smooth sauce. Hollandaise and its flavored cousin, bearnaise, are made by whisking together egg and butter while gradually heating the mixture until it thickens.

Like most cooks, I was under the assumption that the real difference was that one uses vegetable oil and the other butter. In fact, more important is that they are constructed differently. In a hollandaise, the water is whisked into the fat, where it is dispersed; in a mayonnaise, the fat is whisked into and dispersed in the water. The lecithin in the egg yolks (and, to a lesser extent, in butter) makes it possible: Without it, the fat and water wouldn't emulsify. (In other sauces, the emulsifying agent can be found in garlic, as in a traditional egg-free aioli; in mustard; or in butter, as in a beurre blanc. But nothing else is as efficient as egg yolk.)

Standing in his lab at the French agronomical research institute, INRA, in the Latin Quarter of Paris, This explains the principles of his sauce. The Kientzheim is really a hollandaise turned into a mayonnaise, a warm one, made with butter instead of oil. Much like Alsace is part French and part German and altogether different from both.

It seems as simple as that. But the sauce also contains browned butter, what the French call beurre noisette. That everyday ingredient, which most of us produce to some extent every time we fry food in butter, is what This says is the challenging part, not the emulsification. "It is so difficult," he said. "The butter should be cooked so that the milk solids are caramelized. But it must not be burned. I once asked Pierre [Gagnaire] how to make a perfect beurre noisette. Pierre admits that it is something he does not fully master."

The two once spent an entire session at Madrid Fusion, the annual conference on cutting-edge cooking, talking about and demonstrating beurre noisette to an audience of chefs. "They hated it and thought we made fun of them," This said. "But it was an honest attempt to discuss one of foundations of cooking."

Beurre noisette was made slightly less risky once Gagnaire suggested some insurance. By gradually spooning in a little liquid -- water, juice or milk -- at just the right time, the cook can slow down the process while building layers of flavor. Using a flavored liquid adds yet another dimension.

The chefs at Madrid Fusion might have taken the beurre noisette demo lightly, but others are giving serious attention to This's Kientzheim sauce.

Although by no means as commonplace as the classic sauces, it has already been featured on the menus of several Paris eateries, not only at Pierre Gagnaire but also at Pascal Barbot's jazzy and luxurious 25-seat restaurant L'Astrance and at all brasseries and bistros in the Freres Blanc group, including the famous 24-hour eatery Au Pied de Cochon and the venerable La Fermette Marbeuf.

Its future will depend on whether it can get the same kind of play outside its birthplace.


Sauce Kientzheim

Viestad, author of "Where Flavor Was Born" and host of the public television series "New Scandinavian Cooking With Andreas Viestad," can be reached at or His column appears monthly.

© 2010 The Washington Post Company