Namely
Coumarin is an aromatic substance that is one of 24 allergens regulated by Europe. Its name comes from "cumaru" which is the name of the Tonka tree (in an Amazonian language). Indeed, its beans contain 1 to 3% coumarin. It was W.H. Perkin in 1868 who first succeeded in synthesizing the compound (Perkin reaction). It is also found in honey, green tea or cinnamon. Its scents are reminiscent of smells of freshly cut hay with however many notes and nuances (hazelnut, almond, vanilla...).