CITRONELLA OIL, JAVA

Java citronella oil is obtained by steam distillation of fresh or partially dried stems and leaves of Cymbopogon winterianus Jowitt – the so-called mahapengiri – which is grown in Southeast Asia, India, China, and Indonesia, as well as in Central and South America. It is a pale yellow to pale brown liquid with a slight, sweet, floral, rose-like odor with the strong citrus note of citronellal.
d²⁰₂₀ 0.880–0.893; n²⁰_D 1.467–1.473; α²⁰_D ?5 ° to 0 °; solubility: 1 vol in not more than 2 vol of 80% ethanol at 20 °C; opalescence is sometimes observed when ethanol is continuously added; ester number (after acetylation): min. 250, corresponding to 85% acetylizable compounds (calculated as geraniol; this percentage includes citronellal, since it is converted quantitatively into isopulegyl acetate under the acetylation conditions); carbonyl number: min. 127, corresponding to 35% carbonyl compounds (calculated as citronellal).
Java citronella oil may contain up to 97% acetylizable compounds and up to 45% carbonyl compounds, depending on the time of harvesting. It is used extensively not only in perfumery, but also as one of themost important raw materials for the production of citronellal. In addition, a fractionwith a high geraniol content is obtained from the oil. Both citronellal and the geraniol fraction are starting materials for the synthesis of a large number of other fragrance compounds. The oil produced in Taiwan and in Java contains, in addition to the major components, citronellal (31–40%) and geraniol (20–25%), citronellol (8.5–14%), geranyl acetate (2.5–5.5%), citronellyl acetate (2–4%), and many other minor components.
Annual worldwide production was reported to be >5000 t in 1971 and is now ～1800 t. The main producers are China (1000 t), Indonesia (250 t), India (200 t), Vietnam (150 t), and Latin America (150 t).