Ask The Food Lab: What The Heck is Confit?
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"What the heck is confit?"
Can you please explain the process of confit? I know the classic is duck, but there must be other foods that use this technique. I am kind of hiding in shame just not getting it when reading instructions for this. Thanks!
—Sent by finsbigfan
I understand the confusion. Cover your meat in oil and cook it? Isn't that like, deep-fat frying? Doesn't the meat dry out or turn greasy?
The process of confit differs from deep frying in one key way: temperature. While deep frying typically takes place at temperatures between 325 and 450°F, confit preparations are done much lower—an oil temperature of around 200°F, sometimes even cooler.
But before we jump there, what does the word mean, and where does it come from?
The word confit (pronounced "kon-FEE") derives from the French verb confire, which simply means to preserve. Traditionally, confit simply refers to any sort of preserved food, whether it's meat, fruit, or vegetables. This preservation takes place by slowly cooking food in a liquid that is inhospitable to bacterial growth. With fruits, this is generally a very concentrated sugar syrup*; with meats and vegetables, a pure fat. Once cooked, the food is then packed into containers and completely submerged in the liquid, creating an impenetrable barrier and preventing any further bacterial growth. Since the just-cooked food is nearly sterile as it is submerged and is cut off from any potential bacterial contamination sources, it can be thusly stored for a very long time indeed. Properly confit'ed duck legs, for instance, can last several weeks in a cool room, several months in a refrigerator. Confit fruit can last for years.
* Sugar syrups in low concentrations are a good medium for bacteria, while higher concentrations become increasingly more hostile.
With certain foods—most meats—this storage phase is nearly as important as the initial cooking phase as muscle and connective tissue slowly break down and tenderize. A well-matured piece of confit duck leg should nearly melt in your mouth, and this is largely the appeal of the cooking method.
While the method was originally created as a matter of necessity—meats needed to be preserved in the days before refrigeration—as with many such foods, the process lingers on as a matter of good taste. Originally, meats destined to turn into confit—duck legs, goose, gizzards, kidneys, pork bellies, etc.—would be cured overnight in a mixture of salt and aromatics, the salt further creating an inhospitable environment. These days, they're cured simply because, well, it tastes damn good.
Another interesting modern-day twist is that the term "confit," originally a noun, is now used as a verb in modern English-speaking kitchens. "I'm going to confit this pork belly," or, "Let's serve those lambs' tongues confit'ed." You see confit on a menu? Chances are it has not been aged and stored under its fat or syrup for more than a few days. Heck, it may have been cooked just that morning.
How it Works
So we come again to the question: If we're submerging something in fat and cooking it, how come the results are so different from deep-fat frying?
With deep fat frying, the end-game is a crisp, crunchy surface, and the means to get there? Dehydration. A high temperatures, water is very rapidly and forcefully expelled from surfaces due to evaporation. When you drop a battered cod filet or a breaded chicken finger into hot oil, its water content quickly turns into steam, bubbling up and out of the oil. Meanwhile, the high heat triggers the Maillard reaction, a series of chemical reactions that develops flavor and turns foods that delicious golden brown. Cooking times are measured in minutes or seconds, and as soon as the food is done, it's retrieved, and served.
A confit, on the other hand, is a much cooler affair. Generally, cold or room temperature fat is poured over the item-to-be-confit'ed, then it's placed in a relatively low temperature oven, say, 250 to 275°F. During the course of cooking, the fat temperature will not rise much above 190 to 200°F—hot enough to break down tough connective tissue, but not hot enough to boil water or cause much evaporation. Meats cook and tenderize with virtually no moisture loss or flavor loss. Cooking times are measured in hours, rather than minutes.
Confit is to deep fat frying what barbecue is to grilling. Low and slow versus fast and furious.
While confit is most commonly seen with duck or goose legs—it makes sense, considering it's a technique that stems from southwest France—as a cooking method, it's ideal for any number of meats that are suitable for low and slow cooking. That is, any meats with a good deal of connective tissue that begs for tenderizing. Pork belly is wonderful cooked confit, particularly if you finish it with a deep fry to crisp the exterior (like finishing your slow-cooked ribs over the grill to give it a crust). Animal tongues of all makes are great. Mexican carnitas are essentially confit'ed pieces of pork shoulder that have been shredded and crisped.
Even chicken wings can benefit from being cooked using the confit method, turning extra juicy and tender in the process.
Cooking vegetables confit will achieve similar results—ultra tender texture, concentrated flavor—but takes far less time. Alliums—garlic, onions, and the like—make for a great confit condiment, and take about an hour to prepare, for instance.
One common misperception many folks have about confit is that it is necessarily a fatty food. That food is submerged in fat for hours, so that fat must make its way inside, right? Not so. Indeed, the fat is largely a surface treatment for muscles. While it is true that it may find its way between the larger muscle groups and will cover the entire piece of meat in a thin layer of fat, it will not penetrate very far into the meat itself. This is easy to see simply by cutting open a large muscle group and examining the inside. It looks virtually the same as meat cooked through any other low-and-slow method, such as braising or steaming.
The fat's true purpose in a confit is twofold: temperature regulation, and creating an environment inhospitable to bacterial growth if preservation is the goal.
In Modernist Cuisine, Nathan Myhrvold et. al claim that using other controlled-temperature means of cooking can achieve results similar to confit. Simply by steaming a piece of meat until tender and coating it in a thin layer of fat, for instance, you can get a product that is indistinguishable from a true confit—at least, a confit that is eaten immediately after cooking. I have not replicated this end-result myself, but it seems quite logical to me.
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About the author: J. Kenji Lopez-Alt is the Chief Creative Officer of Serious Eats where he likes to explore the science of home cooking in his weekly column The Food Lab. You can follow him at @thefoodlab on Twitter, or at The Food Lab on Facebook.