For years, the idea that searing meat helped prevent moisture loss was a cherished and oft-cited piece of culinary doctrine. It made sense and seemed consistent with people's experiences, so it was accepted, largely unquestioned, for nearly a century.
In recent years, however, the pendulum has swung the other way, with large numbers of people now declaring the theory to be pure nonsense — a myth, like fairies or leprechauns.
It's been "debunked," they say, by "science."
Introducing the "Debunkers"
You can easily identify one of these "debunkers" by the distinct air of superiority they adopt in chat rooms, message boards and blogs — anywhere the topic of searing and moisture loss is being discussed.
Ironically (though not, perhaps, surprisingly), they've bought into this supposed debunking with the same blind credulity they attribute to those on the other side of the argument: They've simply heard or read that searing doesn't seal in juices, found the argument to be compelling, and then just filed it away under "things I've decided to believe."
The only trouble is, they're wrong.
And we're about to see why. But before we do, let's take a more detailed look at the theory that searing yields juicier meat, so we can have a better idea of exactly what the debunkers think they've debunked, and on what basis they think they've debunked it.
To do so, we'll need to define what we mean by searing. That's the very center of the question, after all, so we should make sure we're all talking about the same thing. Let's start by quickly summarizing the attributes of dry-heat cooking.
Dry-heat cooking refers to any technique where heat is applied to the food without using any moisture.
Examples would be heating the food with hot, dry air as in an oven, or with heat conducted directly from a hot pan.
In the case of meat, dry-heat cooking also results in the formation of a thick, flavorful "crust" on the meat's surface. This is caused by a chemical process called the Maillard reaction, which is responsible for browning and flavor development, and will only happen in temperatures of at least 310°F.
Since water boils and turns into steam at 212°F, moist-heat cooking methods (such as simmering or braising) can't generate enough heat to form this outer crust. Only dry-heat cooking methods can, methods that include grilling, roasting, sautéing — and searing.
One of the most common applications of searing is with meat that's about to be braised, as a way of improving its appearance and developing the Maillard flavors that braising alone cannot. Typically, the meat's entire outer surface is browned in this way, not just the top and bottom. So with a cube of beef, all six sides of the cube would have to be seared.
But with meat we're about to braise, we don't care about "sealing in" juices. Properly braised meat is going to be moist and juicy no matter what. Searing before braising is done for reasons of appearance and flavor only.
As such, we're not concerned here with searing as it relates to the browning of meat prior to braising. For the purposes of this discussion, "searing" refers to the act of quickly browning a steak or other tender cut of meat, over a very high (i.e., 450°F or higher) heat, sometimes using a small amount of fat, as a part of a cooking procedure that uses dry-heat methods exclusively.
Claim Vs. Counterclaim
Now that we've nailed down a definition of searing, we can move on to examining the question that's at the center of this controversy. On the one hand we have The Claim:
"Searing meat seals in juices."
And The Counterclaim:
"No, it doesn't!"
Versions of The Claim can be traced as far back as 350 BC, when the Greek philosopher Aristotle wrote:
"...the parts nearer to the fire are the first to get dry and consequently get more intensely dry. In this way the outer pores contract and the moisture in the thing cannot be secreted but is shut in by the closing of the pores."
Pores? This is cooking we're talking about, not face cleanser. We'll stipulate that a New York strip steak doesn't have pores. But if this notion of meat having "pores" is the basis for The Counterclaim, the debunkers have been debunking the wrong theory. No one is seriously suggesting that searing helps prevent moisture loss by shutting the meat's pores. And anyway, give Aristotle a break. He also thought that the Sun orbited the Earth — so picking on him is a bit like doing an end-zone dance after beating your dog at checkers.
The Von Leibig Connection
The modern version of The Claim is often attributed to a 19th century German chemist named Justus von Leibig, who was concerned, among other things, with nutrition.
Specifically, he sought to understand what happened to a food's inherent nutrients under different cooking techniques. How, for example, could these nutrients be extracted and concentrated? Indeed, von Leibig would go on to found the Oxo company, which still exists today as a manufacturer of meat extracts, bouillon cubes and related food products (though it's not related to OXO International, makers of the "Good Grips" brand of kitchen utensils).
His theory was that submerging a piece of meat in cold water, then gradually heating the water to a simmer to cook the meat, would result in the meat's interior liquids (and thus, the nutrients and other essential properties such as flavors) being drawn out of the meat and into the cooking liquid.
Conversely, he thought, quickly cooking the meat by submerging it in boiling water would create a barrier that prevented any liquid from passing in or out of the meat.
So von Leibig was talking about boiling or simmering meat, not searing it. Thus the barrier he describes has nothing to do with the crust formed through the Maillard reaction. He happens to have been wrong about the barrier, but von Leibig's theory had nothing to do with The Claim at all. The fact that his theory of boiling meat has come, over the years, to be associated with The Claim, appears to be largely a misunderstanding.
So much for the strategy of "debunkage by association." Having withstood the attempts to dismiss it on a technicality, The Claim can now be judged on its own merits.
Debunking the Debunkers
The most common objections to The Claim (or the theory that searing meat helps to "seal in" juices) seem to focus on the word sealing, which the theory's opponents, the "debunkers," gleefully seize upon as proof that The Claim is bogus.
They hear the word "sealing" and suddenly turn into Perry Mason: "Aha!" they cry, as if they've just caught you in some narrow, linguistic trap they'd been carefully and painstakingly devising. It's like telling someone, "I just flew in from the coast last night," and having them they jump up and shout: "But you didn't fly at all! The plane flew. You just sat there." The debunkers don't ever seem to tire of playing this game.
Predictably, the main thrust of the debunkers' objection to claims of "sealing" is that anything short of being literally waterproof fails to meet the standard. At best, it's an argument indicative of someone who isn't even trying to be reasonable. They're just arguing with you for the fun of it. We're not talking about encasing the meat in Lucite. We're cooking it, not making paperweights out of it.
In fact, we'll gladly stipulate that cooking meat leads to moisture loss. No question about it. But The Claim has nothing to do with creating waterproof meat. All it says is that searing meat — cooking it quickly over high-heat with a little bit of fat — helps to prevent moisture loss. It "seals in," or "prevents the loss of," moisture. No, not totally — just more than cooking it any other way.
And that's the only relevant measurement anyway: whether searing results in a juicier steak than any other method of cooking. Otherwise, someone could claim that not cooking meat at all "seals in juices," a statement that clearly does not make a useful contribution to a discussion on cooking methods.
Is it Time for the "Science" Yet?
So far, The Claim is still alive and well. Meanwhile, the debunkers have absolutely been dying to talk about science. It's their trump card — or at least they think it is. And we've probably made them wait long enough, so let's do it. What about all that "science?"
As it turns out, there's not much real science the debunkers can turn to for help. The best they've come up with is some version of the following "experiment:"
- Begin with two similar steaks. Call them Steak "A" and Steak "B."
- Weigh each one and make a note of its weight.
- Sear Steak "A" only.
- Now place both in an oven and cook each one until its internal temperature reaches some predetermined level — 135°F, let's say.
- Weigh each steak again.
- Determine how much less each one weighs now compared with before cooking, and express the difference as a percentage of its original weight.
We're then asked to imagine (which is, after all, so much easier than actually conducting the experiment, what with the hassle of having to do it over and over again, under laboratory conditions and all) that the seared steak has lost a greater percentage of its original weight than the unseared one.
They pause expectantly, perhaps waiting for you to collapse at their feet from the sheer, relentless force of their science.
So Much for the "Science"
Instead, the only thing collapsing is the experiment itself. By assuming that water loss is the only reason a steak might weigh less after it's cooked, the exercise exits the world of science and veers into the realm of nonsense. We're not told why we should accept this assumption. We're not even told that it is an assumption. Maybe we weren't supposed to notice.
But since the experiment's conclusions are based solely on weight, wouldn't it be reasonable to ask if cooking might cause a steak to lose something besides water? Like fat, maybe? Unfortunately, the experiment doesn't take the fat variable into account.
That's quite a significant error, because fat is a lot less dense than muscle. Therefore, a pair of uncooked steaks might weigh exactly the same, yet have different fat-to-muscle ratios. When cooked, the fattier one might lose more weight than the leaner one — even if they're both cooked the same way. In other words, the different post-cooking weights might be more a function of fat content than water content. But without controlling for the fat variable, we'll never know.
By positing a model in which fat doesn't exist, only protein and water, the experiment proves nothing at all — at least not to anyone in the reality-based community. Ultimately, by failing to meet even the most minimal standards of experimental validity, it's the experiment itself that ends up being debunked.
With the evidence for its supposed "debunking" now in tatters, The Claim (or the theory that searing meat helps to "seal in" juices) faces one last test — the taste test. The theory's opponents, the "debunkers," are invited to participate.
The Taste Test
Imagine you're a contestant on one of those TV chef competitions. As your final challenge, you're given a steak — a beautiful, thick ribeye or strip steak. Your task: Prepare that steak the best way you know how. It should be juicy, flavorful and visually appealing. And no, you're not competing against your dog this time. You're up against professional chefs who know a thing or two about cooking a steak. Will you:
- Quickly sear the steak at a high temperature to produce a brown, outer crust, before finishing the cooking at a lower temperature, either in the oven, or using a grill, broiler or sauté pan? Or,
- Employ some other method of cooking that you think would produce a better result? Poaching, perhaps? How about cooking it en papillote? Then again, maybe a turn in the microwave would be best.
Or, to put it another way: You must serve the judges one of the two steaks from the experiment we described earlier: Steak "A," which was first seared to form a nice outer crust before finishing it in the oven, or Steak "B," which was cooked in the oven with no searing. Quick! What's it going to be — Steak "A" or Steak "B?"
Your instinct tells you that superior cuts of beef like those that come from the rib or short loin primal cuts need to be cooked quickly, using dry-heat and high temperatures, to preserve tenderness and juiciness; and that searing helps develop flavor and texture while enhancing appearance.
Meanwhile, a glance at the steak that was cooked in the oven without first searing it shows a finished product that is tough, gray, flavorless, and not especially juicy. That's because oven cooking alone takes longer than oven cooking preceded by a high-temperature sear. This longer oven time means that those vast lagoons of juices you sought to preserve by forgoing the searing have spent that extra time slowly simmering the surrounding muscle fibers. We're talking shoe leather here. Surely you're not going to serve that steak, are you?
Or to put it yet another way: Which of those two steaks would you rather eat? Are you willing to put your theory where your mouth is?
Conclusions & Wrap-Up
In the end, this may be the best way of distinguishing those who really believe in what they're arguing for, from the ones who are just being ornery. It also suggests a way to dampen the debunkers' enthusiasm for their claim that searing doesn't yield a juicier steak: If you're so sure that an unseared, oven-baked steak is so superior, then from now on, that's the only kind of steak you get to eat.
Too bad it could never be enforced. It would be fun to hear the debunkers go silent for a while.