Whether you love or loathe cilantro, guacamole wouldn't be the same without it.
Cilantro: delightful element of delicious tacos and pico de gallo -- or horrid herb of death that smacks of soap? Like Facebook's Timeline and every episode of "Glee" ever, there's an undeniable "love it or hate it" quality about cilantro.
Actually, the haters are backed by some respected culinary tastemakers: Ina Garten (aka Barefoot Contessa) and Top Chef Fabio Viviani are the latest celebrity chefs to side with cilantrophobes, as they recently told our TODAY.com team. And Julia Child confessed to Larry King in a 2002 interview that she if she ever sees the herb in something she'd ordered, she would pick it out and "throw it on the floor." Harsh.
On Team Cilantro: behavioral neuroscientist Charles J. Wysocki, of the Morell Chemical Senses Center in Philadelphia. Wysocki has been attempting to pinpoint the polarizing nature of coriander leaves -- better known, of course, as cilantro. Wysocki has studied preferences for cilantro in twins, both fraternal and identical. In identical twins, if one twin hates the smell of cilantro, the other is more likely to hate it; the flip side is true, too -- if an identical twin loves the smell, the other will likely love it, too.
"That does not hold for fraternal twins," explains Wysocki, adding that these findings "suggest very strongly that whatever it is that people underlies the preference is genetically determined."
But what is it about cilantro that some people find so intensely offensive? To begin to find out, Wysocki has used gas chromoatography, a contraption that uses heat to separates a complex mixture of molecules -- like cilantro -- piece by piece, allowing researchers to identify each individual compound, by using both the instrument and their own noses. The GC, as it's called, warms the cilantro, and as it heats up, that "soapy" smell is released. About 10 minutes later, the pleasantly herbaceous cilantro smell is emitted -- but the typical cilantro hater still can't smell it.
"What we think might be happening is the person who hates cilantro is, in fact, detecting the soapy odor. But what they seem to be missing is the nice, aromatic, green component," says Wysocki, who thinks the smell of cilantro is quite pleasant. "It’s possible that they have a mutated or even an absent receptor gene for the receptor protein that would interact with the very pleasant smelling compound."
Hear that, cilantro haters? You're mutants, says a scientist. (We kid, we kid.)
As the theory goes -- and Wysocki is quick to remind that this is still speculative -- cilantrophobes may not be able to pick up the scent of a compound called dodecenal, which gives the cilantro that lovely fresh scent we cilantrophiles know so well. It's even possible, Wysocki allows, that those soap-smellers may have something called specific anosmia, which is the lack of perception of an odor for a specific compound, when the smell is otherwise intact.
Readers, what about you? Whether you love cilantro or can't stand it, make your case in the comments. If you hate it -- is it because of the soapy smell/taste, or something else?
- Bites: Cilantro -- love it or loathe it?
- Phantom smells may be a sign of trouble
- Sniff test: Living without a sense of smell
Follow cilantro-lover and msnbc.com health editor Melissa Dahl on Twitter: @melissadahl.