In setting out to blog about food, the psychology of it, and its impact on our brains and bodies, I wanted to begin with what should be, in the best of circumstances, our first food. I'll get there in a minute, by way of a new study about the elusive fifth flavor, umami.
Until recently, the concept of a fifth flavor was not widely accepted in the United States. Outside of Japan, the word umami was virtually unheard of beyond the kitchens and tables of chefs and food fanatics. Add umami to the quartet of sweet, sour, salty and bitter. Umami is widely known to enhance all other flavors.
New research from Philadelphia's Monell Chemical Senses Center, published in The American Journal of Clinical Nutrition, proves that our tongues really do have receptors for umami. It is just that the signaling pathways are different from those of all the four other flavors.
It turns out that breast milk has a tremendous amount of umami in it. I should say, human breast milk, since cow milk seems to have only trace amounts of umami (10 to 20 times less than human milk).
Umami serves as a signaling device to alert our brains and bodies to the presence of protein. Now if you are reading this, you probably don't suffer from a shortage of protein, but much of the rest of the world still does, and we all did until quite recently in human history. (Those woolly mammoths were not quite as easy to fell as a feedlot steer.) So just as bitterness seems to serve a warning role, alerting our taste receptors and brains to a possible poison, and saltiness signals the presence of healthful minerals, umami is there, at least in part, to say, "hey, good source of protein here, get it while it's hot."
Like the four other primary flavors, umami is part of our survival equipment. In a world before the FDA and nutrition labels on foods, we had only our taste receptors to guide us. The umami taste helps us to identify—and favor—protein-rich foods. Umami is the taste quality associated with numerous amino acids, especially the amino acid L-glutamate, or glutamic acid, which also happens to be the most abundant neurotransmitter in our nervous system.
Glutamate, does that sound familiar? As in monosodium glutamate, the bad boy of take-out Chinese food? Yes, that is the very same stuff; you can find it at your local Asian market by the packet or the ten-pound bag. Most bouillon cubes are loaded with it. Accent brand "flavor enhancer" advertises that it has 60% less sodium than salt, which is true, since it is almost pure MSG. The fast-food industry uses tons of the stuff. Why? MSG is like the crack cocaine of flavor: a synthesized chemical reduction of what would otherwise be a perfectly healthy and naturally occurring substance.
Truth be told, MSG itself really does not appear to be that harmful, even in large doses. High levels of glutamate are naturally present in many protein-rich foods, including meats and cheeses, vegetables such as mushrooms, peas and tomatoes. And it is present in what is meant to be our first food, human breast milk.
Soy sauce and Worcestershire sauce are basically liquid umami in a bottle. Most meats and protein-rich foods are full of it: chicken stock, beef, miso. Shiitake and many other mushrooms are rich in umami. The word itself is on loan from Japanese, and translates to something closest to tasty, brothy, meaty, or savory. A Japanese scientist at Tokyo Imperial University coined the term more than a hundred years ago, in 1908, to describe the qualities of dashi, a broth made from seaweed, shiitake, and dried bonito fish flakes.
Parmesan cheese is loaded with umami, which is why pasta, or just about anything savory, tastes better with it sprinkled on it (save the rinds of your Parmesan wedge to add to soup or stock for a serious flavor boost). Parmesan is not alone; many hard fermented cheeses are rich sources of umami—my friends and I used to refer to these as the cheeses that made your mouth itch. Fermentation most often produces the glutamates and the richest sources of umami: wine, cheeses, yeast (think Vegemite and Marmite, too). Anchovies are loaded with umami and are incorporated into so many local dishes from Scotland to Japan and all points in between.
Southeast Asian cuisine relies heavily on fermented shrimp paste and fish sauce for its umami qualities. Thai and Vietnamese cooking wouldn't be the same without it.
I should be fair to my own culinary and genealogical heritage and note that Italians have their own version of this called Garum Colatura, which dates back to ancient Rome—literally the castings or "leakage" from the bottom of the barrel, when preserving and packing anchovies in salt. Stinky stuff. It is a principal ingredient in many dishes to be had south of Naples, along the Amalfi coast. Here in the States, it's harder to come by, but the acclaimed Zingerman's deli and their amazing food catalog have it. It's an exotic import and much more expensive than the Asian equivalent.
Even if umami is old hat to you, you might not realize how many calorie-laden and carbo-rich snack foods are loaded with it. The new findings suggest it is downright unfair, a kind of bait-and-switch played on the brain, to heavily dose empty calorie snack foods with umami, because it makes us want to eat—and eat—them.
I dare you to go look in your pantry, or stroll down the snack foods aisle, even at your gourmet organic emporium whatever. Hydrolyzed vegetable protein? Torula, autolyzed, or hydrolyzed yeast? How about the oh so healthy sounding yeast extract or soy extract? Hmmmm, what about protein isolate? These all qualify as natural flavorings, and many are even organic. They are really just MSG in its natural state. Now that is not such a bad thing in and of itself, but think about it: Glutamates are there to signal our brains and enhance other flavors so that we consume proteins.
What does it mean when we adulterate all of these high-fat snacks and carbo-rich, protein-poor foods with glutamates? Surprise: We eat tons of them, and we end up supersized. Not so smart, but don't tell that to Frito-Lay, the Colonel, or that happy clown under those smiling golden arches. What do their french fries have that yours or mine don't? "Natural beef flavor," which according to McDonald's contains hydrolyzed wheat—you guessed it, basically MSG that the FDA says does not have to be labled as such.
What is the "natural" process that yields hydrolyzed wheat? Boiling the grains in hydrochloric acid and then bathing them in a neutralizing solution of sodium hydroxide (that would be lye). I apologize, I said at the begining that this would be a blog about food. Somehow we have arrived at a less natural process than simmering mushrooms and fish flakes in broth. But you try pulling away from a drive-thru window with a steaming bowl of miso soup.