For the Food Lab, Kenji Lopez-Alt debunks some old wives’ tales related to cooking steak.
Myth #2: “Sear your meat over high heat to lock in juices.”
The Theory: Searing the surface of a cut piece of meat will precipitate the formation of an impenetrable barrier, allowing your meat to retain more juices as it cooks.
The Reality: Searing produces no such barrier-liquid can still pass freely in and out of the surface of a seared steak. To prove this, I cooked two steaks to the exact same internal temperature (130^0F). One steak I seared first over hot coals and finished over the cooler side of the grill. The second steak I started on the cooler side, let it come to about ten degrees below its final target temperature, then finished it by giving it a sear over the hot side of a grill. If there is any truth to the searing story, then the steak that was seared first should retain more moisture.
What I found is actually the exact opposite: the steak that is cooked gently first and finished with a sear will not only develop a deeper, darker crust (due to slightly drier outer layers-see Myth #1), but it also cooks more evenly from center to edge, thus limiting the amount of overcooked meat and producing a finished product that is juicier and more flavorful.
If you’re serious about home-cooked steak, the “Further Reading” section at the bottom of this piece is your new best friend.