Fennel (Foeniculum vulgare) is a flowering plant species in the carrot family. It is a hardy, perennial herb with yellow flowers and feathery leaves. It is indigenous to the shores of the Mediterranean but has become widely naturalized in many parts of the world, especially on dry soils near the sea-coast and on riverbanks.
The aromatic character of fennel seeds derives from volatile oils imparting mixed aromas, including trans-anethole and estragole (resembling liquorice), fenchone (mint and camphor), Limonene, 1-octen-3-ol (mushroom). Other phytochemicals found in fennel seeds include polyphenols, such as rosmarinic acid and luteolin, among others in minor content.
The oil is steam distilled from the seeds.