slaving over the stove, cooking dinner with your girlfriend or boyfriend, and you get
into a heated discussion about the dish needing more salt. To you it’s not salty enough,
while to her (or him), it’s already way too salty. What’s going on? Why can’t you
ever agree on the seasoning?
As it turns out, some of us really do taste things differently. Just like variations
in eye color, there are variations in our taste buds. What one person senses and
perceives can differ from what another person experiences. In terms of taste, there are
a number of known differences, one of the most prominent being
Supertasting was accidentally discovered in the 1930s when a DuPont chemist, Arthur
Fox, unwittingly spilled phenylthiocarbamide (PTC) powder. He didn’t notice, but a
colleague complained of a bitter sensation from the dust kicked up in the air. Curious,
Fox started testing on friends and family (this was clearly in the days before internal
review boards) and found that about one in four couldn’t discern any bitterness.
More recent research by Dr. Linda Bartoshuk has shown that those of us of who can
sense PTC can be broken down into two groups: a supertaster group
that detects these compounds as unbearably bitter (~25% of the general population of
European heritage) and a second group of medium tasters who find
the compounds bitter, but not overwhelmingly so (50%).
If you’re looking at the percentages and thinking “Mendelian trait?,” you’re right:
you’re a supertaster if you’ve inherited both dominant alleles from your parents. As
with other Mendelian traits, the percentage breakdowns do differ by ethnicity and
gender. For example, white females have a 35% chance of being supertasters, while white
males have only a 10% chance. Asians, SubSaharan Africans, and indigenous Americans have
a much higher chance of being supertasters.
If you’re wondering if you’re a supertaster, there are a couple of ways to
Method #1: PTC or PROP test strips
The best way to tell if you’re a supertaster is to see if you can taste the chemical
directly. Two chemical compounds are commonly used to test for taste differences:
phenylthiocarbamide (PTC) and 6-n-propylthiouracil (PROP).
Place the test strip on your tongue and let it rest there for 10 seconds. You’ll
know if you’re a supertaster if you experience an extremely bitter taste. Supertasters
will generally yank the piece of paper out of their mouths really fast. Medium tasters
(individuals with only one dominant allele) will sense a mild but tolerable bitter
taste, and nontasters will enjoy the pleasant sensation of, well,
Method #2: Taste bud count
If you don’t have test strips, you’ll have to stick your tongue out (all in the name
of science, of course). Because supertasters generally have more taste buds on their
tongues than medium tasters, the low-tech (and low-accuracy, unfortunately) way of
checking to see if you’re a supertaster is to count the fungiform papillae, which
contain taste buds and are correlated to the number of taste buds you have. You’ll need blue food coloring, a cotton swab or spoon,
and a sheet of binder paper (i.e., three-hole punched paper that has a 5/16″ /
Place a drop of the food coloring on the cotton swab, and then stain your tongue
with it. Place the paper on top of your tongue such that you or a partner can see the
tongue through one of the holes. Choose the area that is densest with spots, usually the
front portion of the tongue. Count the number of pink dots visible (fungiform papillae
aren’t stained by the food coloring). If you count more than 30 papillae, you’re
probably a supertaster. Normal tasters tend to have between 15 and 30 papillae, while
nontasters have fewer than 15, on average. These numbers are only broad generalizations,
so it’s hard to say for sure which group you fall into based on the counts.
Counting the number of fungiform papillae visible in a
three-hole-punch-sized area of the tongue takes a bit of dexterity and good
lighting. Look for the densest area, the location of which varies among people.
Count the lighter dots in the circle. This image shows approximately
Being a supertaster or a nontaster isn’t necessarily good or bad. Supertasters might
find some foods—especially dark-green leafy vegetables such as kale, cabbage, broccoli,
and Brussels sprouts—to be overly bitter, because of phenylthiourea-like compounds that
their tongues can sense. Supertasters generally also find astringent, acidic, and spicy
foods to be stronger, due to the higher number of taste buds and thus larger number of
cells experiencing oral irritation. Researchers have found that in addition to bitter
tastes (tested using quinine), supertasters also experience sweet (sucrose), sour
(citric acid), and salty (sodium chloride) tastes as being more intense. Nicotine is
more bitter to supertasters, and sure enough, supertasters are less likely to smoke.
Caffeine also tastes more bitter, and researchers have found that supertasters are more
likely to add milk/cream or sugar to coffee and tea.
Keep in mind that supertasting is just one of many factors that impact our sense of
taste and our food habits. Physiological factors and disease can affect our sense of
taste, as can our experiences. Stress leads to an increase in the hormone cortisol,
which, among other things, dampens the stimuli strength of taste buds. Our environment
can also impact our taste buds. For example, drier conditions change the amount of
saliva in the mouth, resulting in a decrease of taste sensitivity.
As we touched on earlier, temperature also impacts taste sensation, just as it
impacts our sense of smell: foods served warmer (by some accounts, above 86°F / 30°C)
will be detected as stronger by the taste buds than colder dishes, due to the heat
sensitivity of at least one of the receptors (TRPM5) responsible for taste. Foods served
below body temperature won’t register as warm, so if you want a dish—say, a spinach and
bacon salad—to taste stronger, serve it on the warmer side (but below body temp). If you
want a dish to carry milder tastes—e.g., to moderate the bitterness of beer or sweetness
of ice cream—serve it colder.
Finally, if you’re a cilantro hater—if it tastes like dish soap and you can’t stand
it—you’re not alone; even Julia Child hated cilantro. While there’s no known scientific
mechanism or genetic marker for determining this reaction, preliminary research based on
differences between identical and fraternal twins does suggest that a distaste for
cilantro is genetic.