As the leaves change color from vibrant green to warm autumnal hues, sweet seasonal flavors come to dominate menus and kitchens across North America. From pumpkin spice to apple pie, vanilla is a quintessential ingredient in seasonal and holiday baking. But for those seeking a subtle twist on tradition, the tonka bean, known scientifically as the seed of the Dipteryx odorata tree, offers an enticing alternative to the classic vanilla bean.

Celebrated for its complex aroma, the tonka bean is often described as a sweet blend of cinnamon, clove, almond, vanilla, and caramel, sometimes with hints of cherry or freshly cut hay. Its intoxicating fragrance comes from its high levels of coumarin, a chemical compound that gives the bean its signature scent and flavor. However, as a scientific panel for the European Food Safety Authority argues, coumarin also presents potential health risks to those who consume it regularly, for the compound may accumulate in the liver and cause damage over time. Largely as a result of this threat, and despite its alluring aroma, the tonka bean hasn’t risen to the ranks of the vanilla bean as a pantry staple.

The story of Dipteryx odorata is marked by a paradox: The seed is a failed global commodity, and the tree that produces it is a long-lasting commercial success. Once catapulted into international networks of trade for its desirable applications in gastronomy, perfumery, and tobacco industry, the tonka bean’s promise collapsed in the mid-1900s, when coumarin-related health concerns prompted its bans in the United States and government guidance limiting its consumption across Europe. Meanwhile, Dipteryx odorata itself, renowned for its durable, richly grained hardwood known as cumaru, flourished as a reliable export favored for flooring and furniture. This contrast between the seed’s unrealized promise and the tree’s commercial success reveals how human desire, driven by taste and utility and tempered by regulation, can define our relationship to different parts of the same plant.

The Tonka Bean: Aromatic Intrigue

Dipteryx odorata is a large tropical tree native to the Amazon basin, found in present-day Venezuela, northern Brazil, Colombia, Suriname, and the Guianas, as well as nearby islands Trinidad and Tobago. The fruit of Dipteryx odorata resembles a small mango, ripening from a dark green into yellow and mahogany, colors that indicate the final stage of maturity. Its fibrous yellow pulp encases a fuzzy, peach-like pit that holds a smooth, black seed. This seed is known as the tonka bean, a name derived from the Tupi and Galibi languages of Indigenous South America. It is also referred to in Spanish sarrapia in Venezuela and other parts of Latin America. When aged in barrels of rum and dried until they take on a shriveled, raisin-like appearance, tonka beans develop a crystallized white coating of coumarin that intensifies their sweet aroma, signaling their many uses in perfumery, cooking, and tobacco manufacturing.

Traditionally, sarrapia was used medicinally by Indigenous groups, such as the Mapoyo, and mixed-race groups like the Aripao and Jabillal. Guided by elders, one was supposed to consume no more than three fruits per day; local knowledge held that excess could cause fever or body aches. In this context, use reflected a nuanced relationship with the plant that was grounded in moderation, observation, and experience. Yet, despite being safely integrated into local healing practices for centuries, the fruit became a dangerous substance when introduced to Western markets.

Tonka first gained international attention at the beginning of the nineteenth century, when German scientist Alfred Vogel isolated the coumarin compound from the tonka bean. Later, in 1868, British chemist William Henry Perkin synthesized the first sample of artificial coumarin. This innovation allowed the sweet, sophisticated aroma of the compound to be commercialized on an unprecedented scale. By the 1940s, artificial coumarin was exceptionally cheap, making it a cost-effective substitute for natural vanilla to sweets, beverages, and tobacco products. The popularity of artificial coumarin helped expand and maintain global demand for the tonka bean’s aromatic profile, even as the synthetic compound outpaced the natural one in commercial use.

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Throughout the nineteenth and early twentieth centuries, this growing demand transformed parts of Venezuela into centers of sarrapia collection and trade. In 1882, the government of Venezuela issued a decree to “monitor and control the export of sarrapia beans” by dividing the forest into different administrative zones and assigning specific sarrapiales, or tracts of land rich in cumaru trees, to families for annual harvesting. This system, which persisted even after the decree was invalidated in 1890, created a legacy of land use that’s still observable today in families’ continued respect of these invisible boundaries in their tonka bean harvesting.

During the sarrapia boom, harvesters known as sarrapieros traveled each year to their allotted sarrapiales to live and work from February to May. Entire families joined this seasonal migration, living in temporary forest settlements where every member of the household performed a specific, gendered role in the collection, processing, and sale of tonka beans to their commercial center in northern Venezuela’s Ciudad Bolivar. Men surveyed the state of the harvest at the beginning of every season, often venturing deep into the Caura River Basin to reach remote groves. Once the family came together to gather the sarrapia, men split the fruit open, while women and children extracted the beans inside. In just a month of work, a single laborer could collect between 150 to 240 kilograms of beans, a testimony to the intensity of the trade.

“Can We Look at Your Spice Cabinet?”: Fall from Global Prominence

While the sarrapia industry was a major source of profit for many Venezuelans, the industry saw its demise in the 1940s and ’50s after medical concerns and government regulation deflated demand. When scientific studies proved that coumarin caused liver damage in animals, the US Food and Drug Administration moved to ban the tonka bean as a food ingredient in 1954. The FDA’s decision, however, has long been criticized by chefs, gastronomists, and tonka bean lovers as inconsistent. Tonka beans contain coumarin levels comparable to those found in everyday ingredients such as cinnamon, lavender, and licorice, none of which are banned in the US. Critics also note the exaggerated scale of the perceived risk: As reported by Ike DeLorenzo for The Atlantic, to reach toxic levels of coumarin, one would need to consume twenty-five to thirty whole tonka beans, or around 250 servings, in one sitting. In contrast, as food chemists Andreaa Claudia Toma, Simone Stegmüller, and Elke Richling write, European regulators have adopted a more measured approach, recommending a tolerable daily intake (TDI) of 0.1 milligrams of coumarin per kilogram of body weight as a conservative limit to minimize the health risks.

Despite, or perhaps because of, its controversial status, the tonka bean has gained a reputation as a “forbidden fruit” in culinary spaces. Chefs have spotlit the bean in desserts, cocktails, and savory dishes, using its rarity and semi-legal status to entice diners. At Chicago’s Alinea restaurant, Chef Grant Achatz famously incorporated tonka into his menu, spurring exaggerated interest from both the public and federal authorities. As a result, writes DeLorenzo, in 2006 the FDA asked Achatz “Can we look in your spice cabinet?” before conducting a raid of Alinea’s kitchen in search of the illicit ingredient, bringing attention to the restaurant and the bean as flavor worth breaking the law for. The tonka bean’s return to kitchens after the collapse of the industry, and despite the looming FDA ban, shows how human desire and taste continue to shape the history of this plant species.

The Cumaru Tree: “The Hardest Wood Known to Man”

In contrast to the tonka bean’s rapid rise and fall as a global commodity, the Dipteryx odorata tree itself has a stable presence in both the Amazon rainforest and the industries that have come to depend on it. Known as the cumaru or kumaru tree, it has a commanding presence, standing at an average height of between 20 and 30 meters with trunks that measure between 50 and 70 centimeters in diameter. Its size and longevity mirror its stability in the context of the world economy, as its wood has long been celebrated for its density, durability, and rich grain, and its sometimes referred to as “the hardest wood known to man.” As a result, cumaru wood, also known as Brazilian teak, has remained a valuable lumber for applications in flooring, furniture, and construction.

Recent expansions of botanical knowledge regarding the cumaru tree underscore the rainforest giant as both symbolically and physically stable. According to a 2025 study conducted in Panamanian forests, the cumaru tree is uniquely resilient to lightning. Biologists observed that the trees remained unscathed after several lightning strikes, and some even appeared to benefit from these incidents, as the strikes damaged parasitic vines and competing vegetation surrounding the trunk. In this way, the Dipteryx odorata tree embodies a combination of ecological resilience and commercial reliability, while the seed remains a reminder of how regulation and risk can curtail even the most alluring of natural commodities—standing (tall) as a living testament to the divergent fates of its seed and its wood.

Dipteryx odorata reminds us that a single plant can carry a multitude of stories: tales of local tradition and global appeal, medicinal uses and potential threats to human health, and small seeds producing celebrated giants of an industry. Together, these narratives show how human preferences, judgments, and practices shape the ways we value and interact with the natural world. The Plant Humanities Initiative at Dumbarton Oaks seeks to explore plant-human relationships like these, and to underscore the intricate connections between plants and human society.