Dipteryx odorata (commonly known as “cumaru”, “kumaru”, or “Brazilian teak”) is a species of flowering tree in the pea family, Fabaceae. The tree is native to Central America and northern South America and is semi-deciduous. Its seeds are known as tonka beans (sometimes tonkin beans or tonquin beans). They are black and wrinkled and have a smooth, brown interior. They have a strong fragrance similar to sweet woodruff due to their high content of coumarin.
The seeds normally contain about 1 to 3% of coumarin, but rarely it can achieve 10%. Coumarin is responsible for the seed’s pleasant odor and is used in the perfume industry. Coumarin is bitter to the taste, however, and, in large infused doses, it may cause hemorrhages, liver damage, or paralysis of the heart. It is therefore controlled as a food additive by many governments. Like a number of other plants, the tonka bean plant probably produces coumarin as a defense chemical.
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