MENTHOL

also called peppermint camphor a crystalline organic compound with a strong, minty, cooling odour and taste obtained for centuries from the oil of the Japanese mint; it is used in cigarettes, cosmetics, and flavourings. It belongs to the isoprenoid family, the empirical formula being C10H20O. The most common of the optical isomers (identical formula but different structures) of menthol is the levorotatory form (i.e., a compound that rotates the plane of polarized light to the left) l-menthol, present in mint oil; smaller amounts are produced from citronellal. Racemic mentholi.e., a mixture of equal amounts of l-menthol and d-menthol, the latter being the isomer that rotates the plane of polarized light to the rightis not equivalent to the natural product, because the cooling effect is peculiar to the levo isomer.