Tuesday, October 30, 2007

Understanding Foie Gras

From Fine Cooking Magazine - December 1994 / January 1995

Understanding Foie Gras
Temperature is key in cooking this delicate and luxurious ingredient
By Wayne Nish

Most people have heard of fresh foie gras, but not many people have tasted it, let alone cooked with it. Foie gras is full of romance and the promise of sensual pleasure, but it's also pretty intimidating. Not everyone knows exactly what it is, it's very expensive, and it has a reputation for being tricky to prepare. I got to know--and love--foie gras when I worked as the hot appetizer chef at the Quilted Giraffe in New York City. I must have prepared three pounds of fresh foie gras every day over the course of a year, so I became very familiar with its temperamental ways. Actually, it isn't difficult to work with as long as you understand a few simple principles. Once you taste a crisply sautéed slice, with its deep, rich, powerful flavor and startlingly silky texture, you'll know that fresh foie gras is something worth learning about and trying yourself.

What is Foie Gras?

Foie gras (pronounced FWAH GRAH), which means "fat liver" in French, is the liver from ducks or geese that have been specially fed to produce large, rich livers. This fattening process, called gavage (gah-VAHZH), takes place for a couple of weeks before slaughter. The process involves feeding the birds a rich, corn-based diet using electronic pumps. Gavage has been criticized as being unnatural and unpleasant for the animals, but producers point out that ducks and geese don't chew their food before swallowing, so the pump-feeding doesn't provoke a gag or other disturbing reflex in the bird.

Foie gras is a very rich and potent ingredient, and therefore should be served in small portions, almost always as an appetizer or as a garnish to a dish rather than as a main course. There are lots of ways to prepared foie gras-sautéed, poached, baked, or made into paté or a mousse-but the two standard methods for fresh foie gras are sautéing slices to be served hot and baking whole livers in a terrine to serve cold.

Foie gras is produced in many parts of the world, notably in the Gascony, Périgord, and Alsace regions of France, and in Eastern Europe. There was no production in the United States until the early 1980's, when the demand became strong enough to make commercial operations feasible here. Still, there are only two commercial producers in the U.S., one in the Hudson Valley of New York and the other in California's Sonoma Valley.

Duck, duck, goose.

In the U.S., only ducks are raised for foie gras, not geese. According to Ariane Daguin of D'Artagnan, a leading distributor of fresh duck foie gras, geese are more susceptible to disease and are more temperamental than ducks. They must be fed more frequently and for a longer period of time, and they demand the comfort of the same "goose girl" to aid in their daily feeding.

Nonetheless, geese are still raised for their livers in Europe. Foie gras d'oie (FWAH GRAH DWAH) is an even richer product than duck liver (foie gras de canard). This higher fat content makes goose liver less suitable for sautéing because the high heat causes more fat to melt. Conversely, the lower heat used in terrine production makes goose liver suitable and economical for this cooking method.

Recognizing Quality

Here in the U.S., there is little romance to the purchase of foie gras. There are no colorful market stalls of vendors who have personally raised their animals. The cook who wants to prepare foie gras at home can contact a mail-order distributor who sends the liver by overnight courier.

The USDA requires that fresh foie gras sold in this country be classified by size and quality. The higher the grade, the fewer blemishes the liver will have and the larger it will be. Grade-A livers must weigh at least one pound, B's are between eight and fifteen ounces, and C's are under a half-pound. The size of the liver will determine how "veiny" it will be. The basic vein network is the same in all the livers, so bigger specimens have relatively more "meat." You want a liver with few veins because if they're not removed adequately they can mar the smooth texture of the finished dish. Also, bits of blood from the veins will discolor the foie gras when it's cooked in terrine form.

Foie gras is a fresh product that is highly perishable, and it has a very high fat content. It must be kept at a constant temperature of 38° to 40° F. during its handling, packing, and distribution to keep it wholesome and fresh. In fact, the ducks themselves are chilled before the livers are removed so that the livers stay cold and firm and keep their natural shape.

Judging Texture

To the novice, a brick-hard grade-A liver would seem to be the most desirable. In fact, however, its firmness means it has an extremely high fat content, which will result in more fat melting off during cooking. With a high-fat liver, you can wind up with a small piece of sautéed liver or a smaller baked terrine. A grade-A liver with a bit of give, but not sponginess, is the most desirable. A very spongy liver will have a low fat content and will burn when sautéed. I found that out the hard way in my earlier days at the Quilted Giraffe. When I first handled one of these spongy livers I thought it felt a little different, but I decided to go ahead and cook it. The second I put a slice in the sauté pan, I knew that it was gong to burn, so I quickly threw in a knob of butter, which saved the day. If you do get a liver that feels spongy and bounces back when you press it and you have time to return it, contact the supplier, who should willingly replace it with a better one. If you don't have time, or you don't realize that you have a spongy liver, just remember the butter trick.

Handling Before Cooking

The only real preparation that fresh foie gras needs before cooking is some careful deveining. Some cooks like to let the livers come to room temperature before deveining. This softens them and makes it slightly easier to pull the veins from the livers. I prefer to devein the livers when they're cold. First of all, as with any meat, the warmer foie gras gets, the more susceptible it becomes to bacteria. Also, as the liver softens, it becomes very fragile and is more liable to break apart. It's difficult to get nice slices from a broken liver, and for terrines, more fat will be rendered off during baking. For sautéing, I don't think a lot of deveining is needed, other than removing the obvious pieces from the surface of the liver. The sautéed slices will be golden brown so you won't see any discoloration from blood. For terrines, however, a little more extensive deveining is required. You'll get the most vein with the least disintegration of the liver if you know the way the veins run.

To Devein

Unwrap the liver and blot it with a paper towel. The liver should be a pale beige; trim off any yellow or green spots. Each liver consists of two lobes, one slightly larger than the other. If there are a few bits of thin, white membrane clinging to the outside, pull them off. Gently pull apart the lobes with your hands, noting that they are connected by a vein through the center of the two lobes. Cut this vein with a knife. Hold one lobe firmly in your hand and with a pair of flat-end tweezers, grasp the end of the vein that was severed. Gently pull with a slow, even motion. In the best case, the gentle pull will cause the rest of that portion of vein hidden inside the liver to pull free. For more extensive deveining, gently probe with the tweezers, a paring knife, or you fingers to find and remove the network of veins. Sometimes a clump of white fat is nestled between the two lobes, attached to a very thin membrane, which should be peeled off with your fingers. Keep the deveined livers cold until you're ready to cook them.

Delicious Either Hot or Cold

The trend in restaurant cooking these days is to offer sautéed slices of fresh foie gras rather than the more traditional foie gras terrine. Until the early 1980's, only canned terrines were available in the U.S. due to import restrictions, so people tend to associate even freshly made terrines with the old-style canned versions. Also, sauté recipes generally require far less preparation and labor to make, so they're preferred by restaurant chefs.

Quick, High Heat for Sautéing

Sautéing foie gras is by far the most simple way to prepare it. Nonetheless, while the cooking is accomplished in a matter of minutes, you must use your sense of touch to identify the precise moment when the liver is fully cooked but not overcooked. As foie gras cooks, a lot of fat is rendered off so the slices go from cold, firm slices that are full of solidified fat to softer, springier slices that have had much of the fat cooked off. As you cut your slices for sautéing, touch them to gauge the texture when cold. During cooking, feel them again so you can monitor the transformation. Knowing exactly when foie gras is done to perfection is an acquired skill, so the best thing to do is to cook a lot of it!

When you sauté foie gras, you want to use very high heat so that the outside is quickly seared, which forms a delicious crisp surface and helps to keep the slice from completely melting away. I heat my black iron sauté pan until it's very hot. The slices cook quickly and should be served right away, so be prepared with your plates and other ingredients.

Long, Slow Cooking for Terrines

While terrines may be currently less fashionable in American restaurants, they are a wonderful way to experience the sublime flavor and texture of fresh foie gras. Making a terrine yourself is a lot less expensive than buying one from a gourmet store, too. Another advantage for the home cook is that terrines can be made up to a week ahead of serving. In fact, they need at least two days "curing" time after baking in order for the flavors to develop. Probably the most important thing to remember when making a terrine is to be gentle-handle the liver gently, use gentle heat and a water bath for cooking, give the terrine enough time to rest and cure, and take care when slicing the finished terrine.

Strategies for Gentle Cooking

The best pan to use is a heavy, enameled-iron terrine mold. Oven-proof ceramic or porcelain works too, but the heavier the mold the better so that the heat is distributed slowly and evenly. The terrine mold should be carefully wrapped in foil and placed in a bain-marie (a water bath), which can just be a roasting pan filled with boiling water. The actual cooking time will vary depending on the size of your foie gras and on the shape of your terrine, but I recommend setting your oven to 325 degrees F, which should keep the water in the bain-marie at about 160 degrees. The most important temperature to gauge is the internal temperature of the liver. You can check this during cooking by inserting an instant-read thermometer into the center of the terrine. Don't push it in so far that the tip gets close to the bottom or sides of the mold or your reading will be too high-you want to know the temperature at the heart of the livers. One hundred ten degrees produces a rosy pink terrine, which is the way I like it because the texture is very creamy and silky. Cooking it rare like I do is one more reason to be sure to keep it cool during handling.

My terrine recipe is very basic, just some flavoring from a sweet-wine marinade and salt and pepper. The seasonings really need to be impregnated in the liver. I like to dissolve the salt in the wine so that I can actually taste the saltiness before I marinate the liver, and so that the salt penetrates the liver more evenly than if I just sprinkled it on. If you unintentionally undersalt a terrine, the best remedy is to serve it with a salty-savory relish, like an onion and cranberry compote, which will help balance the flavors.

Wayne Nish changed careers in his early thirties and went to cooking school. He landed a job at the renowned Quilted Giraffe in New York and soon after became the executive chef at La Colombe d'Or. He is now the co-owner, with partner Joe Scalice, of two Manhattan restaurants, March and La Colombe d'Or.

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