I bet that you've read in many recipes that meat must first be "sealed" in order to be grilled properly. In essence, sear it at a high temperature on each side, and then finish cooking it at a more moderate temperature. For the same reason, when preparing boiled meat, you should first soak it in boiling water, then wait until the water returns to a boil, and submerge the meat again. Even for the classic stew recipe, it is recommended to cook the meat on high heat, then lower the temperature and leave in the sauce for several hours. The purpose of this procedure, in theory, is to make the outside of the meat nearly impermeable, so as to seal its juices inside and render it tender and full of flavor. But does it really work?
The answer, sorry to say, is no - and I know that may displease many of you. But I have good news: if we move past sealing, I can say that this technique is still useful for other purposes. First, though, let's see what happens when we seal our meat. Sealing consists of quickly searing a piece of meat on a frying pan or grill at a high temperature. According to the myth, it serves to "cauterize it" and close the pores from which it’s liquid would escape. In reality, by subjecting the meat to the high temperature, as we now all do due to habit, the Maillard reaction is activated. However, this does not "seal" anything (because, physiologically, meat does not have "pores"): rather, it gives the meat a nice brown color and generates aromatic substances that are pleasing to the nose and palate. Therefore, searing the meat at 150° C at least before cooking has nothing to do with it. Which is somewhat of a big deal!
It may be interesting to find out that the concept of "sealing" meat dates back as far as 350 BC. Aristotle was the first to discuss it. “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”.The fact that this procedure dates back more than 2,300 years ago, may raise some suspicion on the fact that it is corroborated by scientific evidence. Unfortunately, in the 19th century, Justus vn Liebig, inventor of the "bouillon cube" (actually, he did not invent it, but we'll talk about that another time), confirmed the Aristotelian theory. In fact, Liebig claimed that by immersing the meat in cold water and then cooking it, the meat's juices were extracted. On the contrary, by placing the meat boiling water, a barrier was created that kept the juices inside. In fact, in subsequent years, experiments performed in serious laboratories, have shown that the sealing done to preserve the juices is a myth. And not only that: sealing actually EXTRACTS liquids. This is for a very precise reason: the surface of the meat that comes into contact with the high temperature dries out, its salts are then concentrated and, by osmosis, the water passes from the inside of the meat to the outside. The longer that this process goes on, the more that the poor piece of meat is dehydrated. What determines, then, the juiciness of our T-bone steak? It's simple: the temperature that is reached inside. The higher it is, the drier the meat will become. Sometimes it takes very little to bust a myth.
