http://www.seriouseats.com/2013/06/the-food-lab-7-old-wives-tales-about-cooking-steak.htmlMyth #1: "You should let a thick steak rest at room temperature before you cook it."The Theory: You want your meat to cook evenly from edge to center. Therefore, the closer it is to its final eating temperature, the more evenly it will cook. Letting it sit on the counter for 20 to 30 minutes will bring the steak up to room temperature—a good 20 to 25°F closer to your final serving temperature. In addition, the warmer meat will brown better because you don't need to waste energy from the pan to take the chill off of its surface.
The Reality: Let's break this down one issue at a time. First, the internal temperature. While it's true that slowly bringing a steak up to its final serving temperature will promote more even cooking,
the reality is that letting it rest at room temperature accomplishes almost nothing.To test this, I pulled a single 15-ounce New York strip steak out of the refrigerator, cut it in half, placed half back in the fridge, and the other half on a ceramic plate on the counter. The steak started at 38°F and the ambient air in my kitchen was at 70°F. I then took temperature readings of its core every ten minutes.
After the first 20 minutes—the time that many chefs and books will recommend you let a steak rest at room temperature—the center of the steak had risen to a whopping 39.8°F. Not even a full two degrees. So I let it go longer. 30 minutes. 50 minutes. 1 hour and 20 minutes. After 1 hour and 50 minutes, the steak was up to 49.6°F in the center. Still colder than the cold water comes out of my tap in the summer, and only about 13% closer to its target temperature of a medium-rare 130°F than the steak in the fridge.
You can increase the rate at which it warms by placing it on a highly conductive metal, like aluminum,* but even so, it'd take you at least an hour or so to get up to room temperature—an hour that would be better spent by, say, actively warming your steak sous-vide style in a beer cooler.
*protip: thaw frozen meat in an aluminum skillet to cut your thaw time in half!
After two hours, I decided I'd reached the limit of what is practical, and had gone far beyond what any book or chef recommends, so I cooked the two steaks side by side. For the sake of this test, I cooked them directly over hot coals until seared, then shifted them over to the cool side to finish.* Not only did they come up to their final temperature at nearly the same time (I was aiming for 130°F), but they also showed the same relative evenness of cooking, and they both seared at the same rate.
*Normally I'd start them on the cool side and finish them on the hot like in this recipe, but that method would have obscured the results of this test.
The cooking rate makes sense—after all, the room temperature-rested steak was barely any warmer on the inside than the fridged-steak, but what about the searing? The outer layer of the rested steak must be warm enough to make a difference, right?
It takes five times more energy to convert a single gram of water into steam than it does to raise the temperature of that water all the way from ice cold to boiling hot.
Here's the issue: Steak can't brown until most of the moisture has evaporated from the layers of meat closest to the surface, and it takes a hell of a lot of energy to evaporate moisture. To put it in perspective. It takes five times more energy to convert a single gram of water into steam than it does to raise the temperature of that water all the way from ice cold to boiling hot. So when searing a steak, the vast majority of energy that goes into it is used to evaporate moisture from its surface layers. Next to that energy requirement, a 20, 30, or even 40 degree difference in the temperature of the surface of the meat is a piddling affair.
The Takeaway: Don't bother letting your steaks rest at room temperature. Rather, dry them very thoroughly on paper towels before searing. Or better yet, salt them and let them rest uncovered on a rack in the fridge for a night or two, so that their surface moisture can evaporate. You'll get much more efficient browning that way.
