This food doesn't taste right ... or is it me?

As I was looking for a good sangria recipe some weeks ago, I came upon this article in Gourmet about how our understanding of the scientific basis for "flavor" as changed, not to mention what sorts of implications this might have for those who prepare -- and sell -- food.

One of the interesting bits is how different the science on taste is from what you probably think it is:

[N]early everything humans think they understand about taste is wrong. For generations, textbooks have trumpeted two universal truths about taste. Truth No. 1: There are four basic tastes--bitter, sweet, sour, and salty. Some have added a fifth basic taste, umami, from the Japanese umai, which refers to the savory, meaty taste first isolated in 1908 in Tokyo by Japanese chemist Kikunae Ikeda. Truth No. 2: Different tastes are detected on different parts of the tongue. This "taste map," popularized by Harvard's Edwin G. Boring in the 1940s, has been scoffed at by scientists for years. "That's just hokum," says Jeannine Delwiche, senior sensory and psychophysics scientist at Firmenich, another industry powerhouse. "You can taste everything everywhere."

Recently, however, even the first truth has come into question. "There are no basic tastes," says Michael O'Mahony, a sensory scientist at the University of California, Davis. "The notion was arbitrary, made up by a chap named Hans Henning in 1916." The idea is misleading, O'Mahony continues. "The first question you should ask is, 'What are basic tastes?' Well, there are more than four types of taste receptors, so it can't be that. There are more than four ways a chemical can react with a receptor. There are more than four types of neural codes those receptors can send to the brain. Lots of scientists felt they had to describe tastes using one of the four categories. It's silly."

Flavor is a result of what happens with taste-receptors in the mouth (including but not exclusively those on the tongue) and with olfactory receptors. The 40 or so kinds of taste-receptors interact with the chemicals in what you're tasting (yes, all your food is made of chemicals!) and create a nerve impulse that sends a signal to the brain. Meanwhile, the 300 or so olfactory receptors send their own smell-signal based on the volatile components of your food. The taste-signal and the smell-signal are correlated in the brain to make the flavor you're experiencing.

The science behind the whole process, needless to say, is both complicated and cool.

"Taste is like a chair with four legs," explains [Cornell University flavor chemist Terry] Acree. "Before, we only had one leg--flavor chemistry. Now we're building the other three: how a chemical reacts with the receptor; how that receptor communicates with the brain; and how the brain processes that information into behavior." Once scientists have identified the chain of messages each chemical sends to the brain, they can begin to manipulate that conversation. The chemical gustducin, for example, is part of the signaling mechanism between receptor and brain. If you remove gustducin from mice, they drink bitter liquids as if they were water. If researchers can find less-invasive ways to stop taste receptors from telling the human brain, "Hey, this food is bitter," suddenly those Brussels sprouts go down a lot easier. As does a child's medicine.

Among other things, a better understanding of the receptors and of the various compounds that might interact with them (including in ways that block them from sending their usual signals) might allow food manufacturers to devise additives that block the unpleasant aftertaste of potassium chloride in low-sodium tomato juice. For the consumer who wants a V8 without racking up fully a fifth of her daily allowance of sodium (which is what you get in a serving of the regular version of V8), taking the tinny aftertaste out of the low sodium analogue seems like a good thing.

Assuming, of course, that that's all the taste-blocking additive does when ingested. Indeed, for those who like to know what they're ingesting, the article notes that such an additive "would be in such a tiny amount that it could be referenced in the 'artificial flavors' category and not be specifically listed on the label."

In a world where manufacturers are trying to producing lower sodium (or lower fat, or higher fiber, etc.) foods -- and to make these healthier foods taste good enough that consumers will buy them again -- this is clearly a line of research with a constituency. The author of the article, though, sees farther reaching implications:

As scientists begin to home in on the biological foundation of different likes and dislikes, an even more tantalizing possibility arises: In the future, each of us will likely be able to identify our genetic predispositions to food. We might even have a food type, just as we have a blood type: I'm broccoli positive, you're pumpernickel negative. To be sure, this does not necessarily equate to a like or dislike. As [CEO of Redpoint Bio Dr. Ray] Salemme cautions, we can learn to modify our responses. "There are many things you might not like the first time you taste them, such as single-malt Scotch, but you learn to like them. A lot." The direction, though, is clear: Soon each of us will carry around our own periodic table of what food chemicals we respond to. You'll no longer be able to ask dinner guests merely if they eat meat; you'll have to send them a detailed questionnaire.

I think the prospective dinner guest questionnaire is probably going overboard. If someone offers you a meal in his home, it is a gesture of hospitality, one that is not usually undone if you're served a dish that is not your favorite. Just as a gracious host does his best, so does a gracious guest. That this kind of worry even comes up points to the fact that for a great many humans, eating is not a simple matter of fulfilling a biological need. Rather, food has become a source of comfort -- or of adventure.

To date, part of the adventure has been in exploring how various foodstuffs, prepared in different ways, tickle our taste buds. With more information on how to block (or enhance) certain of the signals traveling from palate to brain, the terrain of that adventure changes. Potentially, it could be used to widen our culinary horizons, but we could also use such information to narrow them, to keep us from tasting anything out of our comfort zone.

In some ways, that might be a horrible waste of arugula or Brussels sprouts.

There are other potential uses of flavor blockers that rub me the wrong way for what I think are reasons of style. The article brings us to the kitchen of a London restaurant:

"Lots of chefs have said they don't care about this stuff," says Chris Young, a chemist who worked as a food-research manager at The Fat Duck. "They just care how the food tastes on the plate. That's fine. But this research will eventually trickle down to every level of cooking." So can he imagine using a taste blocker at a high-end restaurant? "Sure. Savory ice cream. Sugar is inherently necessary to get the particular texture that ice cream has. You need it to depress the freezing point and give you enough solids. But for a true savory ice cream, you'd need to use sugar but block the sweet taste."

Taste blockers present one solution to the problem of savory ice cream, but to me it doesn't feel like a terribly inspiring one. It's an engineered solution based on plentiful technological resources, not the kind of ingenuity you'd get from a chef who took more of a MAKE or MacGyver mindset to harnessing the qualities of her ingredients. Sugar is not the only edible substance that can lower a freezing point, and there may be other ways to boost the solids in one's savory ice cream. (If it were me, I'd investigate avocado flesh as a potentially useful component.)

Part of the adventure of eating, after all, is in the artistry of the food's preparation, and good art is often born of creative response to limitations.