The Sensual Aroma of the Tonka Bean

The sens marketing, wrinkled black seeds of the tonka bean (Dipteryx odorata) produce an unforgettable aroma that is part vanilla, part almond, with hints of cinnamon and maybe something fruity like cherry. Despite this one-of-a-kind scent, tonka bean is actually illegal to import into the United States because it contains coumarin, which can cause liver and heart damage in high quantities.

While a small amount of coumarin is found in the seeds, it is not enough to cause these negative side effects and it is diluted during cooking. In fact, the coumarin content of tonka beans decreases when roasted and even more when ground. Furthermore, it would take a very large quantity of tonka bean—more than 30 whole beans—to have any adverse health effects from the coumarin content.

“Understanding the Science of Scent: The Limbic System

In addition to its sensual fragrance, tonka bean has a range of medicinal virtues: it is considered an antiseptic, an antispasmodic, a decongestant and a sedative. It has also been used as a treatment for rheumatism and tuberculosis.

As the demand for tonka bean grows, farmers are working to cultivate these seeds responsibly and sustainably. They require a lot of sun, fertile soil and consistent watering. However, growing tonka bean is difficult because the trees are slow-growing and prone to diseases and insects. Companies that specialize in planting tonka beans help preserve the rainforest and provide income to local farmers. This sustainable cultivation helps protect the tonka bean tree, which is an endangered species, and ensures a supply of this coveted ingredient.