ANETHOLE AND FENNEL OIL          [home]   [topic]

Products of the plant Foeniculum vulgare. The crop below is at Fingal in North-East Tasmania..

Fennel Oil is a pale yellow oil extracted by steam distillation.

From this oil, anethole can be extracted through fractional distillation. Anethole is the molecule largely responsible for the taste of aniseed.

Principal molecules in Fennel oils. Many of these are terpenes.

alpha-pinene                turpentine        2,6,6-trimethylbicyclo[3,1,1]hept-2-ene      C₁₀H₁₆

alpha-phellandrene        2-methyl-5-isopropyl-1,3-cyclohexadiene     C₁₀H₁₆

trans-anethol           "oil of aniseed"        1-methoxy-4-propenylbenzene      C₁₀H₁₂O

gamma-terpinene               1-methyl-4-(1-methylethyl)-1,4-cyclohexadiene        C₁₀H₁₆

fenchone in much smaller quantities but gives the bitter taste          1,3,3-trimethylbicyclo[2.2.1]hept-2-one    C₁₀H₁₆O