This is just an ordinary strip of paper, coated in a chemical known as phenylthiocarbamide,
or PTC.
As an experiment, we’re going to have different people around the office each lick a strip.
You might’ve noticed that Hank’s reaction was intense.
Well, that means that chances are he’s a supertaster, with a higher sensitivity to
the five flavors we know as salty, sour, sweet, bitter, and umami.
It’s a genetically-inherited trait -- and dominant, meaning that only one parent has
to have the supertasting allele, or version of the gene, for their child to feel its effects.
If the kid gets one copy of the allele, they’re what’s called a medium taster, with a slightly
higher sensitivity.
With two copies, they’re a true supertaster.
It’s difficult to measure taste sensitivity, and scientists still aren’t totally clear
how taste is read by the brain, but we do know that supertasters exist because they
can taste things others can’t -- especially bitter substances -- and they have up to twice
the number of taste buds as average tasters.
Each taste bud is composed of between 50 and 150 taste receptor cells, and they sit on
small, mushroom-shaped tongue bumps called fungiform papillae.
If you want to see if you’re a supertaster, you can count the density of your papillae
by swishing around blue food coloring.
The color sticks to the base of your tongue, so you can see the pink bumps better.
Cut a small ring of paper about the size of a hole punch, place it on your blue-and-pink
tongue, and count the number of big papillae within the hole.
Compare with your friends!
Or you can just try these little PTC-coated strips of paper, which taste horribly bitter
to supertasters, slightly weird to medium tasters, and just kinda bland to everybody
else.
Scientists found out about supertasters’ sensitivity to PTC after some of the chemical
exploded in an accident at a Du Pont lab in 1931.
Some workers complained about how bitter it tasted, but others couldn’t taste a thing.
Today, researchers often use a chemical called PROP, which is also more bitter to supertasters.
Both PTC and PROP have similar properties to compounds found in dark green vegetables
like kale and spinach, and with their highly-sensitive tongues, supertasters detect the bitterness.
But it’s not just bitter substances; many supertasters also can’t stand the taste
of overly sweet things like ice cream or acidic drinks like coffee.
The sensory overload on the taste buds is just too much.
So, if you’re one of those people who can’t stand the taste of broccoli and brussel sprouts,
it might just be that they taste a lot worse to you than to your vegetable-loving friends.
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