Hoping for a tasty, succulent Thanksgiving turkey? According to a bit of homespun research by food and science writer Harold McGee, the secret is an ice pack, a meat thermometer, and a touch of biochemistry.
Too many turkeys end up on the table as parched white meat sopped in gravy. The reason is that the breasts dry out before the rest of the bird is cooked through. Leg muscles, for example, are reinforced with connective tissue, tendons and ligaments--gristle, to the tongue. Softening this dark meat takes hours of roasting to turn the collagen into gelatin. And that leads to a culinary conundrum. "For a really nice tasting leg," says McGee, "you want to cook it to 180 degrees Fahrenheit to make sure it has fully gelatinized, but by then the breast will be dry as dust."
Why dry? The reason is that proteins in the breast muscle fibers begin to unfold and stick together even after a short time in the oven. Once denatured, the proteins no longer wrap around water molecules in the cells. By the time the tissue reaches about 140 degrees Fahrenheit, collagen surrounding the muscle cells shrinks, squeezing out the juice. That aromatic sizzle means your bird is turning into parchment.
A few years ago, McGee heard about a Portuguese recipe for a juicy turkey. A friend pointed out the key step--placing stuffing into the space between the skin and breast meat--might act as a kind of insulation to keep the white meat cooler in the oven. McGee, author of On Food and Cooking, The Science and Lore of the Kitchen, decided to investigate. "The wonderful thing about a turkey," he says, "is that it's bilaterally symmetrical, so you can do the experiment and control in the same bird."
That Thanksgiving, McGee tucked stuffing into half of his turkey, then inserted thermocouples into both breasts to take temperature readings. Indeed, the stuffing kept the breast cooler during the cooking. But the strategy backfired: Once the bird was out of the oven, the hot stuffing continued to cook the breast meat. "The recipe works as long as you immediately strip the insulation," he says. "And that's not a nice way to present your turkey."
So McGee repeated the experiment the next November. This time, instead of adding stuffing for insulation, he iced one half of the breast before putting the bird in the oven--giving the legs a head start in the cooking. And although it wasn't a double-blind trial, McGee is certain that the cold treatment resulted in a more succulent bird. "It's a little difficult at a dinner party to have people pay attention to details of texture," McGee admits, "but they did think it was juicier."
If you're game to replicate his results, McGee has a few pointers. First, don't stuff the turkey. The bird will heat up too much before the stuffing is done. Before you cook the turkey, chill the breasts down to 40 degrees with ice packs, leaving the rest at 60 degrees. (But unless you want an experiment in microbiology, make sure the turkey doesn't sit around at room temperature. See tips on cooking turkey and food safety.) Then cook the bird, letting the breast meat heat to 160 degrees and the dark meat to 180 degrees. According to the USDA, this should kill all pathogenic bacteria.
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