ellen's midnight train: thanksgiving chemistry

Last Thursday, I sat in on an American Chemical Society webinar on the chemistry of Thanksgiving cooking. It featured Harold McGee, a contributing columnist for the Times. It was one of the more interesting ACS webinars I've signed up for, and I thought I'd share with you some of the tips Dr. McGee mentioned:

When cooking poultry, you're dealing with different types of muscle between the breast and leg meat, so you want a temperature differential between the two to achieve optimal results. For legs, you want an internal temperature of about 160-165, and for breast meat you want it not much higher than 150 degrees for it to be still moist (though food safety people would say 165 would be safest). Dismembering the bird and cooking the parts at different temperatures at different times would be the way to go to get the best results, but if you are intent on serving the bird in its entirety, then McGee recommends placing ice packs on the breast when defrosting the bird. This helps achieve an initial temperature differential. Clever! (do this several hours before cooking.)

McGee mentioned that brining keeps the meat tender, but it tends to also make it overly salty. It's a matter of personal preference, though brining is especially good if you plan on deep frying the bird.

As for defrosting the bird, he recommends defrosting it naked (i.e. no plastic wrap, foil, etc) in the fridge.

To stuff or not to stuff? Epidemiologists would suggest not stuffing the bird for food safety reasons, and it turns out McGee's answer agrees, though he just says for optimal cooking of the meat, just don't stuff the bird.

He recommends not getting a bird more than 12 pounds.

Why let the bird rest before carving? This is a no-brainer, but he provides an answer that elaborates on moisture loss and retainment on the micro level: when you cook meat, proteins are denatured. Moisture is squeezed out as the temperature rises, but can be reabsorbed when the temperature drops, so let the bird cool down a little, allowing some of the juices to be reabsorbed into the meat.

Don't baste the turkey when it's done cooking. Basting the bird while it's resting just makes the skin less crispy.

McGee recommends not using digital, 'instaread' thermometers, but rather, use those that have detachable, thin probes. The thinner the probe, the better.

As for gravy, McGee discussed a little on the thickeners. Corn starch vs flour? Well corn starch is a pure starch that gives you a cloudy gravy, as opposed to the opaque gravy flour gives you (no mention on if the two taste different). If you're feeling techy, you can try using xanthan gum, which doesn't change the flavor of the juices and thickens more effectively, meaning you can use less of it to achieve the same viscosity. McGee mentions that he tends not to thicken meat juices because think gravies tend to just sit on top of the meat, whereas unadulterated juices seep into the meat.

...and in case you want to watch/listen to the entire webinar yourself, have at it: