The Tonka Bean Is Revered for Its Superb Flavor, But It's Illegal and Might Kill You

All the best stuff is illegal. You're thinking about tonka beans too, right? This flavorful little bean is the golden goose of sweet, haute culinary creations, but you don't want to be caught with the treat in the U.S. Not just because the FDA will put you on their most wanted list, but because, well, the bean may kill you. Honestly, death by world-class dessert might be worth it.

Related Video: 10 Deadly Foods from Around the World

It Will Be Mine. Oh Yes, It Will Be Mine.

The tonka bean is a wrinkly, raisin-like legume from South America. The transcendent flavor and aroma of the bean (it's huge in the perfume world) has been described as having notes of vanilla, cherry, almond, spicy cinnamon, cloves, and probably the dust of unicorn horns. It's so potent that the shavings (how it's usually prepared for consumption) from one bean are enough to top 80 plates. BBC reports that tonka is "the most delicious ingredient you've never heard of."

But if you're an American, you're outta luck — the FDA banned the chemical found in tonka beans in 1954. Any foods containing added coumarin (the chemical in tonka beans) or tonka extract is deemed "adulterated" by the FDA. (It's legal in Canada, though, so have at it!)

Delicious Death

Despite tonka being illegal in the U.S., you'll find it on fancy-shmancy restaurant menus across the country. In fact, the United States is the biggest importer of tonka on the planet. What's going on here?! The spice is apparently so good that top chefs are willing to smuggle it in. Chef Grant Achatz, of Chicago's world-class Alinea, told the Atlantic about a warning call from his tonka supplier: "They said, 'Don't be surprised if the FDA shows up soon.' [...] Two days later, they walked in: Can we look at your spice cabinet?" That's right, the FDA means business, and is out to bust tonka code violators. But should they?

Tonka Bean Creme Brulee with Balsamic-Poached Strawberries, Black Olive Syrup & Vanilla Ice Cream

The big claim is that tonka beans, or coumarin, more specifically, is highly toxic. "As long as you don't use a copious amount of it – obviously a copious amount could cause death – it really is delicious," Thomas Raquel, head pastry chef at the Michelin-starred Le Bernardin in New York, told the BBC.

Wild amounts of anything will likely end up hurting you, but how much coumarin is too much? In studies, relatively low levels of the chemical have proved to cause liver damage in dogs and rats in a few weeks. But, to be fair, there's coumarin in the common type of cinnamon (cassia) that's sitting in your spice cabinet too. Coumarin has also been added to tobacco, e-cigarettes, cosmetics, deodorants, hand soap, shower gels, and detergents. To date, there have been no reported cases of human deaths caused by coumarin, and people have even called to lift the ban.

That's not to say the stuff isn't dangerous. Pinpointing just how dangerous the stuff is seems to be an elusive task. According to the Atlantic, tonka beans were perhaps unfairly subjected to an FDA ban, saying that the agency mistook coumarin for the similarly named trademarked blood-thinner Coumadin. BBC reports that, for most people, the current coumarin consumption limit is probably "ultra-conservative." According to the European Food Safety Authority, 0.1 milligram of coumarin per kilogram body weight (an "ultra-conservative" limit, according to the Atlantic) can be ingested daily over a lifetime without posing a risk to health. But seeing as a single tonka bean is more than enough for dozens of dessert plates, well, accidentally overdosing on tonka is likely not in the cards.

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Written by Joanie Faletto September 20, 2017

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