Is there a cilantro gene? A food scientist clarifies the science.

Few leafy greens garner as many polarized opinions from adults as does cilantro (known outside the U.S. as coriander). The herb, which has been seasoning foods since around year 2 B.C.E., flavors cuisines worldwide, from fajitas to curries. It’s ubiquitous in herb gardens and garnish repertoire. But for all its staying power and goodness, there’s a question of whether there’s a genetic predisposition to dislike cilantro.

One website publishes haiku denigrating the plant. Julia Child detested it, often quoted that she would pick it out and throw it on the floor. There’s no such cultish praise or revulsion for basil or thyme, but cilantro gets special attention.

The explanation that has pervaded popular thought is that there’s a gene that makes cilantro taste ghastly. While it’s most commonly described as “soapy,” here are a few other descriptions floating around:

• bitter
• moldy
• like dead bugs
• like wet dirt

Indeed, there’s reason to believe that at least one gene variant can determine how one perceives cilantro, but it’s more nuanced. Neuroscientist Joel Mainland helps flesh out the science behind the popular explanation of cilantro hatred.

Is there a cilantro gene?

The most accurate way to put this is that there’s strong evidence for gene variants that affect how one perceives cilantro.

“A region of DNA happens to fall in the midst of a bunch of odor receptors that are highly correlated with your liking of cilantro,” Mainland says. The genomics and biotech company 23andMe surveyed about 25,000 people on whether they liked cilantro or thought it smelled soapy. They used the survey results to pinpoint the association with this region of the brain.

Researchers suspect a particular olfactory receptor gene to be the culprit. Some researchers suspect a particular olfactory receptor gene, but that’s as certain as it gets. One study from 2012 identifies the gene OR6A2 as a possibility, which binds to several molecules that give cilantro its signature scent, called aldehydes. It might not be just a single gene that contributes to this pathological dislike, but rather a combination.

How does the gene work?

Part of the soapy smell also comes from cilantro’s composition. The leaf contains aldehydes, which are organic materials with a unique chemical structure. This cilantro-negging gene likely detects these aldehydes.

The presence of aldehydes helps explain the soapy or buggy taste that so many describe. Aldehydes, for one, are a byproduct of the process of fragmenting fat molecules with alkaline lye to create soap. They also fragrant insect body fluids to attract or repel creatures. So why could some people be more sensitive to aldehyde than others?

Mainland references the late chemist George Preti, who he said surmised that it’s crucial to recognize that smells comprise many different molecules. Preti believed that everyone smells this soapy compound in cilantro, but others are more receptive to the good smell, so the soapiness isn’t overpowering.

Can I dislike cilantro without the gene?

It’s not all genetic. There’s an ethnocultural component to whether someone dislikes cilantro. People from cultures that frequently use cilantro in food, like Mexican and Indian, have far fewer people that say cilantro has this soapy taste. The soapy cilantro opinion is more likely to come from someone of European descent, the 2012 paper found.

It’s also a matter of exposure to the leafy green. For example, someone might be born with this specific olfactory reception cluster, but if they’re raised on meals flavored with cilantro, they could overcome what seems like an innate dislike. On the other hand, if somebody doesn’t like cilantro, it doesn’t mean they’re genetically predisposed to dislike it; it could mean they’re not used to its taste.

The team from a 2012 study published in the journal Flavour calculated that genetic variants determine less than 10 percent of cilantro responses.

The second study, which was published in the journal Chemical Senses, takes a similar approach. Geneticists from the Monell Chemical Senses Center asked 527 twins whether they thought fresh, chopped cilantro tastes pleasant and smells good.

Are there cilantro alternatives?

Indeed there are some alternatives if you can’t stand the green.

It’s worth crushing cilantro leaves and mixing them into food rather than eating them whole; this accelerates aldehyde deterioration, which could abate the foulness. Another option is to opt for Thai basil, parsley, lime, or other common herbs.

There’s also a recipe credited to food science writer Harold McGee that creates a mild, pesto-like sauce. It does incorporate cilantro, but may be more palatable.

CHECK, PLEASE is an Inverse series that uses biology, chemistry, and physics to debunk the biggest food myths and assumptions.

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