Do certain physiological traits make some wine critics better than others? In a three-part series this week, Mike Steinberger examines the physiology of the oenophile. On Wednesday, he examined the age-old stoner's question: Do you taste what I taste? Yesterday, he set out to discover whether or not he's a "supertaster." Today, he'll examine whether being a supertaster helps you evaluate wine.
Being a nontaster, albeit an anomalous one, looked like bad news. What wine writer would want to own up to having a genetically inferior palate? What prudent consumer would take wine tips from a certified nontaster? But after numerous e-mail exchanges with (the very patient) Reed, a follow-up conversation with Tim Hanni, and some additional research, I discovered that maybe I didn't need to curse my ancestors and cut out my tongue, after all. For one thing, being a nontaster was not the career death sentence it appeared to be. For another, being a supertaster turned out to be not nearly as good as it sounded; in fact, to the degree that it matters at all, it is probably more of a liability for a wine critic than an asset.
How so? To begin with, supertasters do not particularly enjoy the flavor of alcohol and often complain that it leaves a burning sensation in their mouths. They are also sensitive to astringency and acidity, which can be equally problematic as wine goes. (Evidently, eating is no joy for them, either; according to Linda Bartoshuk, they can't abide spiciness, they don't like fatty foods, and they tend to find all sorts of vegetables overly bitter. All in all, a fun bunch.) The British wine writer Jamie Goode, in his excellent book The Science of Wine, calls attention to the work of Gary Pickering, a professor of oenology at Canada's Brock University. Pickering has been investigating the relationship between PROP sensitivity and wine appreciation and believes that being a supertaster is no blessing when it comes to wine. "I would speculate that supertasters probably enjoy wine less than the rest of us," Pickering told Goode. "They experience astringency, acidity, bitterness, and heat (from alcohol) more intensely, and this combination may make wine—or some wine styles—relatively unappealing."
As wine writing goes, supertasters may also be at a disadvantage demographically. Researchers believe that just 25 percent of Americans are supertasters; around half are tasters, and the remaining 25 percent are nontasters. The categories also divide along racial and gender lines: It is estimated that 35 percent of Caucasian women are superstars, but only 15 percent of Caucasian men fit that bill.
If, as a wine critic, the aim is to appeal to the biggest possible audience, being a supertaster could be a serious problem. As Bartoshuk tells it, supertasters live in a completely unique world of flavor sensations, which suggests that their opinions about wine wouldn't be of much value to anyone except other supertasters. Even being a taster might not be ideal. By far the biggest consumers of wine criticism are male Caucasians, who according to Bartoshuk are also disproportionately represented among nontasters—35 percent of white males fall into this category. So it could be that, from a purely demographic standpoint, the ideal wine critic would be a low-sensitivity taster. (Hanni suspects that some of the more prominent wine critics are indeed low-sensitivity tasters, given their fondness for heavily extracted, high alcohol wines.)
However, engaging in this kind of speculation gives the supertaster-taster-nontaster trichotomy more weight than it deserves at this point. When it comes to understanding sensory perception, we are literally at the tip of the tongue. Here's what we think we know about supertasters: They show extreme sensitivity to PROP and have high fungiform papillae counts. We also know that fungiform papillae are a reliable indicator of sensitivity to the five basic taste sensations: People with very dense concentrations of these structures are more sensitive to bitter, sour, sweet, salty, and savory flavors than people with average or with sub-average concentrations. But while fungiform papillae have been studied exhaustively, much less is known about the papillae on the side of the tongue (foliate papillae) and those toward the back of it (circumvallate papillae)—except we know they also affect how tastes and textures are perceived.
As for the genetic dimension, TAS2R38 is one of 35 bitter receptor genes that have been identified thus far; there may be others. There appears to be little if any correlation between PROP/PTC sensitivity and sensitivity to other bitter compounds. There is considerable debate about whether the TAS2R38 genotype is indicative of overall taste sensitivity; it might be, and it might not be. Most people who show extreme sensitivity to PROP have the two dominant alleles for TAS2R38, but that is not true in all cases. Meanwhile, scientists have identified receptors for sweetness and umami but have no idea which chemical stimuli, like PROP and PTC with bitterness, can reliably test these receptors. Sourness and saltiness are largely uncharted territory. Reed told me that for all these reasons, and also because the concept has been so often misunderstood and misrepresented in the media, many geneticists are reluctant to even use the term supertaster.