Why Does Cilantro Taste Like Soap to Some People?

Cilantro (aka the leaves of the coriander plant) is a tasty herb to most people. A pleasing combination of flavors reminiscent of parsley and citrus, the herb is a common ingredient in many cuisines around the world. However, some people find cilantro revolting, including, famously, the chef Julia Child. Of course some of this dislike may come down to simple preference, but for those cilantro-haters for whom the plant tastes like soap, the issue is genetic. These people have a variation in a group of olfactory-receptor genes that allows them to strongly perceive the soapy-flavored aldehydes in cilantro leaves. This genetic quirk is usually only found in a small percent of the population, though it varies geographically. Interestingly, places where cilantro is especially popular, such as Central America and India, have fewer people with these genes, which might explain how the herb was able to become such a mainstay in those regions. East Asians have the highest incidence of this variation, with some studies showing that nearly 20% of the population experiences soapy-tasting cilantro. There is some evidence that cilantrophobes can overcome their aversion with repeated exposure to the herb, especially if it is crushed rather than served whole, but many people simply choose to go with their genetic inclinations and avoid its soapiness altogether.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           

Can You Drink Water from a Cactus?

You may have heard that you can get water from a cactus if you are ever lost and dehydrated in a desert.* Sounds like a nice survival tip to store away, but is it really that easy? Turns out, a cactus is not actually a spine-covered basin of fresh water. Such a plant would not last long in an arid habitat filled with thirsty animals. Water is truly a precious resource in a desert, so, in addition to their intimidating spines, most cactus species further protect their spongy flesh with acids and potent alkaloids. These chemicals are usually too acrid for most humans to tolerate and are taxing on the kidneys if ingested. The flesh of some cactus species can also cause vomiting, diarrhea, or temporary paralysis—none of which is conducive to your survival in an emergency situation. The notable exceptions to this rule are the prickly pear and one species of barrel cactus, the fishhook barrel (Ferocactus wislizeni). While both of these plants are fairly unpleasant to eat raw, they have less-concentrated levels of the detrimental chemicals and could give you a bit of hydration in a pinch. Cactus fruits are a better bet, though many are also unpalatable if eaten raw.

*All of this, of course, is assuming you are stranded in a New World desert with true cacti. The cactuslike plants found in the deserts of southern Africa and Madagascar are members of the family Euphorbiaceae and are toxic. The milky sap of these plants can burn the skin and mucous membranes and can cause permanent blindness if it gets in your eyes. Definitely don’t try to eat those.