A recent trip to visit a friend at the Cape Cod Hospital proved interesting from a culinary standpoint. See, i'm kind of a compulsive recipe collector, and it turns out that catering behemoth Sodexho, who operates the CCH's cafeteria with a surprisingly high level of quality, publishes recipe cards for patients. Pretty sensible, i think -- people frankly eat like crap in this country, so a hospital cafeteria providing healthy recipes is a pretty obvious step. (Pay no attention to the burger bar i'm writing this in.) Anyway, the first card is a listing of "alternate" cooking techniques. I quotate "alternate" because other than deep-frying and grilling, it's pretty much a roadmap to Cooking 101. Well, except for one thing -- it's 2008 and this supposedly-informative card is telling me that searing "seals in juices."
So let's talk about
Justus von Liebig for a bit. He was one of the 19th century's big pioneers of kitchen science, and a contemporary, more or less, of Louis Pasteur. He was an interesting fellow -- a generalist chemist (in fact one of the founders of modern organic chemistry), a university professor, and an entrepreneur; among other accomplishments, he was the discoverer of nitrogen-based fertilizer and one of the three responsible for discovering chloroform, as well as the founder of one of the most important chemistry journals in the world (
Liebigs Annalen der Chemie, later incorporated into the
European Journal of Organic Chemistry) and the creator of a process for industrial manufacture of beef extract that led to the creation of the modern bouillion cube. But after all this, he's probably best remembered for the idea that searing meat sears in the juices. Yeah... not so much.
Not that long ago I acquired a copy of Paul Aratow's translation of
La bonne cuisine de Mme. E. Saint-Ange (Ten Speed Press, 2005, ISBN 9781580086059), one of the great French home cookbooks of the early 20th century, which through its influence on people such as Aratow (the original chef de cuisine at Chez Panisse), Julia Child, and Madeleine Kamman, may have been the biggest influence on recent American cuisine of any book of its time. Mme. Saint-Ange mentions it. Escoffier supposedly mentioned it. Lots of cookbooks still do. I have no bloody idea why -- as Harold McGee pointed out in the oft-cited-here On Food and Cooking, this is a total falsehood. To explain why, we have to understand a little about the structure of skeletal muscle, which after all makes up the overwhelming majority of American meat consumption. (We, as a country, are not fond of organ meats. That's just how it is.)
Skeletal muscle is made up of a bundle of fibers in which each fiber is a further bundle of long, multinucleate cells containing networks of two proteins, known as actin and myosin, which interact in a sort of telescoping manner (you can check the Wikipedia article). When cooked, many of the proteins within the meat denature and coagulate in very much the same process as I explained in
my last article on eggs; in the particular case of actin/myosin bundles, however, they don't denature so much as contract. This response to heating causes the cell fluids to leak out and move towards the surface of the cut meat; as a result, the overall process causes the meat to physically shrink as it cooks. When these juices reach the surface on a grill or a frying pan, they hit the incoming heat and, essentially, caramelize like sugar in a
Maillard reaction. The resulting dark, crusty substance is what becomes known as fond when it sticks to the frying pan (and is sometimes deglazed with wine or stock to create a pan sauce). Liebig believed that the fond was actually waterproof and was capable of keeping the meat's juices inside rather than having them gush out onto the pan.
Well, modern cookbooks do still recommend the sear, but solely because of its flavor-building properties -- the simple fact is, if you throw a steak in a frying pan, the juices will continue to exude from the meat as it cooks, a point that's readily observed just from the sizzle (i.e. boiling water) you keep hearing up until the moment the steak comes out of the pan. That juice will keep coming out of your steak until it has the approximate consistency of a hockey puck, at which point you will be savagely attacked by a professional chef for wasting the life of an innocent animal on an inedible meal. So what does one do, if Liebig's technique doesn't work?
The easiest way with steaks is just not to cook them past medium if you can at all help it. Even my well-done-loving mother is just fine with a medium-cooked steak if it's got a nice pan sauce on it. But there's other things you can do if you're not making steak. For example, with a roast, the accepted technique is to cook the meat (beef or otherwise) at a relatively low temperature for a long period of time, creating fond at the beginning or end with either a pan searing or a blast of high heat from the oven element. (Poultry can take this a step further; Chinese cooks actually steam chicken and especially duck (in this case it helps render duck's copious amounts of subcutaneous fat) before finishing off with high heat, and Chinese-American cooks have even adapted it to the Thanksgiving turkey. I did it once by accident -- easily one of the best turkeys ever.) Some meats (particularly pork, turkey, and chicken) can be brined -- the salt water is absorbed into the meat by osmotic pressure. A braise or stew begins with a sear, but incorporates the meat juices into its own sauce, which can be used as a gravy for serving. It's in barbecue, though, that we find the cleverest trick of all: collagen.
Meat connective tissue has two major proteins in it -- collagen (the same as in skin) and elastin. Elastin you can't do anything with -- it's rubbery, plasticky stuff that makes up a large part of what butchers refer to as silverskin, and it only toughens with cooking. Collagen is something different though -- give it enough heat, and it denatures into gelatin, which drastically changes the whole picture. While you normally think of gelatin as a wobbly solid, usually fruit (and possibly vodka) flavored, it turns out that for braises and barbecues, gelatin is a critical part of the final mouthfeel, retaining fluid within the meat and lubricating the dried-out muscle fibers that would otherwise go the hockey puck route. In fact, French pot roasts (often referred to as "daubes") often add extra gelatin, usually in the form of a calf's or pig's foot, but also just straight out of the envelope in some recipes, for precisely this purpose. Many older recipes add "larding" -- threading of sticks of pork fat (lardons) through a piece of cheap or low-quality meat to replace fat marbling that would be in a higher-quality cut, producing similar results to gelatin as the fat melts. This is not usually necessary in American meat, which is generally of much higher quality than European, though rumor has it kids are far more likely to dig in when you tell them that the lardons are actually worms. And in extreme cases, like pulled pork, you can punt on the issue entirely -- shred the meat and douse it in some kind of sauce.
So Liebig was flat out wrong, and for some mysterious reason, even though his hypothesis was discredited decades ago, it continues to be propagated in both home kitchens and in the literature. But it doesn't mean it's a bad idea -- the flavor-building attributes of searing are vitally necessary to a palatable piece of grilled, roasted or sauteed (or even braised) meat. Liebig made a great many contributions to modern science, but this is one area he probably should have done just a bit more work.
I close with a story. There's a restaurant in my town (I won't name names as they've changed management since this happened and have apparently gotten better) that used to advertise a T-bone steak special. It was a cheap special and a thin steak, but a half-inch T-bone is still a good-sized piece of meat, so I tried it once on a day when I was feeling rich. It was terrible -- the meat was the same grey color I associate with meat tenderizer, and the side of sauteed onions were barely any more cooked than the onions on top of a pizza get, and not even close to the seductive sweetness of the fairground onions they throw on sausage subs. The meal was edible, but considering it was a local joint with a reputation to uphold, the utter incompetence of the grill person produced something barely worthy of a low-rent steakhouse chain like the Ponderosa. I've no idea how they lasted as long as they did under that management.
