Taste: Surprising Stories and Science About Why Food Tastes Good (7 page)

“Are you sure you want to know?” he asked me of this mysterious fact he possessed.

“Of course I do,” I said, not at all sure at this point if I did.

“You must know that I’m only going to tell you this for your own good. I mean, since you’re writing this book about taste and all.”

Then he said, “When you went to the bathroom while I was in the taste tasting lab with Jennifer, she told me something about you.”

My heart stopped beating. I held my breath.

“She told me I have more taste buds than you,” he said, looking somewhat sheepish, somewhat swaggering. The worst part about it was I knew he was right. Household taste bragging rights belong to Mr. Meat and Potatoes.

The third factor for taster type is genetics, which is also responsible for the traits you get from Mom and Dad. You may have the genes that allow you to taste something such as the bitter chemical PROP. Or you may not. It’s simple genetics
at work. For each trait, such as blue eyes or the ability to taste PROP, you get one gene from your mother and one from your father. If PROP tastes extremely bitter to you, it’s likely that both your PROP-tasting genes (one from Mom and one from Dad) are turned on. If you can’t taste it at all, it’s likely that both your PROP-tasting genes are turned off. And if you have a mild reaction to PROP, you may have one gene that’s on (the one from Mom or Dad) and one that’s off (the other one, from the other parent). In other words, you need at least one “PROP on” gene to react to the compound at all, but two copies of the gene in order to have a HyperTaster reaction to PROP. Keep in mind, however, that your reaction to PROP is not a universal indication of your reaction to other compounds. Just because you can’t taste PROP doesn’t mean you can’t taste PTC (phenylthiocarbamide, another bitter chemical), the bitterness in Brussels sprouts, or the bitterness in beer. In fact, “There are PROP nontasters who are Supertasters [HyperTasters],” says Bartoshuk, just to confound the matter.

Your unique tongue anatomy and genetics combine in an interesting way that results in your own unique experience of food. If you have the genetic ability to taste PROP but a low density of taste buds, you may taste food very differently from someone with a high density of taste buds who cannot taste PROP. And how these traits affect your food choices is even more complicated when you layer on life experiences.

Because of all this complexity, Bartoshuk defaults to a more straightforward test for identifying a HyperTaster: she simply asks how intense some things taste. When we were in Florida, we sampled popcorn, lasagna, peanut butter, and grape jelly. But herein lies the rub. How in the world do you measure this? What would happen if you gave both Roger and me a plate of roasted butternut squash (with sage and brown butter, please) and asked us to rate it? How would you know that his perception of bitterness is the same as my perception of bitterness? Or sweetness? Or saltiness?

The fact is that perception occurs in the mind. As a result, it is virtually impossible to measure accurately. Take the perception of beauty. How pretty is Angelina Jolie? How beautiful is the city of Paris? There is no definitive answer to either of these questions. The answer varies with the individual. Asking about someone’s perception of food is similarly complicated. Each person is biased
(and informed) by his own anatomy, genetics, and life experience. Taste perception is in the mouth and brain of the beholder.

The solution, says Bartoshuk, is to peg taste intensity to something that we
can
measure, such as sound. She conducted an experiment that started with a can of Coca-Cola, a product with a standardized recipe (or formula, as we say in the food development business) for the United States market. Because of this, a Coke in your neighborhood, city, or state will taste exactly the same as a Coke in mine (though it is different in Mexico, where Coke is sweetened with sugar instead of high fructose corn syrup). This wouldn’t be the case if she had used tomatoes or berries or beef, which vary by location, variety, season, and how they’ve been stored. Bartoshuk asked consumers to rate the sweetness of Coke on a scale in which the bottom of the scale is “no sweetness at all” and the top of the scale is “the sweetest you’ve ever tasted.” In this first test, almost everyone put the sweetness at the same place: about two-thirds of the way up.

“You look at that and you think,
Wow! People’s senses of taste are really very similar,
” says Bartoshuk. But this is where things get interesting. In a second phase of the test, she outfitted the testees with earphones and a sound dial. In this round of testing, Bartoshuk used a technique called
crossmodality matching.
Here, a
modality
is a sense. Crossing modalities means using one sense (hearing) to gauge another (taste). She asked the tasters to adjust the volume of the sound they heard through their earphones to match the sweetness of the Coke. The results showed that the group of HyperTasters adjusted the sound up to the level of a train whistle, or about 90 decibels. Conversely, the group of Tolerant Tasters adjusted the sound level down to that of a telephone dial tone, about 80 decibels. A difference of 10 decibels equates to a factor of two. In other words, “That tells us through this matching technique that people with the most taste buds experience twice the sweetness,” says Bartoshuk. Maximum sweet for a HyperTaster is twice as intense as maximum sweet for a Tolerant Taster.

“PROP remains a very good way to identify taster types; if you taste PROP and you are one of the individuals who get a very strong bitter taste, you know that you are an anatomical Supertaster. However, some of those who cannot taste PROP can also have the anatomy of Supertasters; they just don’t taste PROP.” This is all to say that there’s no litmus test for determining your taster type. It’s confusing, to say the least.

What’s also confusing is that the food choices of HyperTasters and Tolerant Tasters are highly unpredictable. If at this point you’re starting to wonder if you are doomed to a life of blandness because you may or may not be a HyperTaster,
fear not. Being a HyperTaster is as much a curse as it is a blessing. Think of all the amazing bitter foods Roger and others like him simply can’t eat. In times of famine or shortage, Tolerant Tasters would be able to sustain themselves on bitter roots and plants while Roger would wither away and die without his meat and potatoes, unable to tolerate the bitter greens he’d be forced to subsist on.

You can’t change the anatomy of your tongue, just as you can’t change your genetic makeup or height. But a height limitation doesn’t mean that you can’t teach yourself to be an excellent basketball player. And everyone—including you—can teach himself to be an excellent taster.

HyperTasters are characterized by an excess of taste buds on the tongue that results in excessive sensitivity. A logical question is whether this might correlate with an excess of any other sensitivity. It makes some sense to me that this might be true. If taste buds hold nerve endings that poke out on the tongue to receive input, it would stand to reason that some other nerve endings might be poking out somewhere else to receive different inputs at excessive levels of sensitivity. Some scientists noticed an interesting correlation in animals, so they set out to test it in humans. Their hypothesis was that an increased sensitivity to bitter tastes (like PROP and Brussels sprouts) might be indicative of more emotional behavior.

The researchers recruited more than a hundred people and split them into three groups based on their sensitivity to PROP: HyperTasters, Tasters, and Tolerant Tasters. To eliminate the influence of personality traits, the participants were asked to complete a questionnaire assessing their characteristics, which were then normalized. The experiment entailed watching movie clips chosen to elicit emotions.

One clip was a three-minute scene from
The Champ
, a 1979 movie about a championship boxer. The scene shows a young Ricky Schroder distraught over the death of his father, trying in vain to wake him up. I’ve seen
The Champ
a handful of times and each time I’m reduced to sobbing out loud. To call this scene heart-wrenching is to understate how hard it is for me to watch. (This will be important!) After being exposed to the movie clip, the participants then rated their emotional state for comparison. At a later date they did the same thing for a clip from
Pretty Woman
, one that’s difficult to watch, in which a man tries to rape
a woman, chosen to elicit anger. A third clip, from a documentary on the processing and usage of copper, which contained no human interaction, was thrown in as a control. It was pretty emotionless and didn’t incite any feelings.

The scientists found significant differences among the HyperTasters’ response to the content that induced anger. Other studies have shown a link between PTC-tasters and depression. The conclusion drawn by the scientists is that HyperTasters may be more prone to emotions such as anger and tension because these emotions provoke reactions at the basic survival level. A sensitivity to bitter tastes also requires action for survival, namely rejecting bitter, possibly toxic food.

As a HyperTaster I totally embraced these findings, since I am highly emotional in both positive and negative ways. But Roger is not. In fact, the reason we work as a couple is that his rock-solid stability anchors my roller-coaster psyche. So these results confused me once again.

Ultimately, this type of conflicting data—two of the same taster types with totally different behavior—is the trouble with statistics. You may be a Hyper-Taster and not recognize Roger’s behavior as your own. In fact, Paul Rozin, owner of the “beautiful tongue” depicted earlier, makes food choices very different from Roger’s. He, too, finds many bitter foods almost unbearable, but he has come to like many of them, mostly through repeated exposure and coming to appreciate the strong sensation they give him. He considers himself an omnivore, and has traveled the world seeking out unique food experiences. I, too, am a HyperTaster and almost an omnivore. I seek out bitter foods like the aforementioned Brussels sprouts. Bitter foods taste bitter to me, but I love the sensation. Roger avoids it. I have to be superattuned to flavor nuances for my job and I’m pretty good at detecting these subtle flavors, lemon zest possibly excepted.

I asked Bartoshuk how scientists are able to make correlations between types of tasters and the food choices we make. Trying to answer this question, Bartoshuk seemed to share my exasperation as she gave reasons why two people of the same taster type might choose very different diets. For example, I may have put a lot more time and thought than Roger into the concept of Brussels sprouts, eventually developing an appreciation of them. People who are brought up in cultures that believe bitter foods are good for them generally end up liking bitter foods. Conversely, if someone has a terrible experience with Brussels sprouts, such as vomiting right after eating them, that person may tend to avoid them because that experience conditioned him to do so, consciously or unconsciously.

“The truth is, you just can’t make predictions for one person,” said Bartoshuk,
“It’s just too complicated. We can statistically do a very good job. You give me a hundred subjects in one group and a hundred in another and I will be able to tell you some things about their
average
behavior that will be right on. But I will miss by a mile with individuals.”

This is the ultimate problem with these groupings of taster type. After people learn about taster types, they seem to want their type to explain why they eat what they eat. But we are complex creatures, each of us living in our own individual sensory world, each of which is colored by a combination of anatomy, medical history, genetics, culture, and life experience. The best way to describe the type of taster I am is that I am a Barb Taster. And Roger is a Roger Taster. That makes you a [insert your name here] Taster.

The bottom line is that your taster type is just one factor among many in why you make the food choices you do.

Everything you’ve just read is barely the tip of the iceberg of what we casually refer to as
taste
.

Taste, taste buds, and the tongue represent a tiny amount of what you experience when you eat food. A smidgeon. An itsy bit. Not a whole heck of a lot.

This is because of the fact that your tongue can taste only a few things, namely sweet, sour, bitter, salt, and savory. There’s absolutely no way to prove how much information the tongue contributes. Many professionals I talked to gave me their own estimates for how much input our sense of taste provides. Some say that only about 5 percent of what we experience when eating is input from our sense of taste. They think that the remaining sensory input—the vast majority—is aroma, which we detect with our nose. Yes, most of what you think you taste is actually smell.

I think 10 percent for taste and 90 percent for smell is a better estimate, but only if you’re dividing the entire experience of eating between just the two senses of taste and smell. What about the other three? When you add the influence of touch, hearing, and sight, things get really interesting. Our experience with food—which we simply call
taste
—is actually a multisensory adventure.

First, I’m going to teach you how the senses work. From there we’ll explore each of the Basic Tastes, the nuances of flavor, and finally, how everything comes together. Deliciously.