A COMPARISON OF METHODS FOR THE EXTRACTION OF THE FRAGRANCE FROM YLANG YLANG

摘要

Ylang Ylang is an essential oil traditionally extracted from the flowers of the tree Canaga odorata. It is used both in high-class perfumes as well as in basic toiletries e.g. soaps and shampoos, the traditional means of extraction being by steam/hydrodistillation. The major objective of the work described in this paper was to evaluate the potential for using Supercritical Fluid Extraction (SFE) with Carbon Dioxide, as an alternative to the traditional technique. A bench scale SFE Extractor equipment was used in the experimental programme, the results being compared with those from steam distillation and hydrodistillation. The SFE programme also incorporated a study on the effect of flower maturity. Extraction performance was based on yield of oil, and chemical composition using Gas Chromatography. Steam distillation tended to produce a product of the 'floral water' type, but hydrodistillation gave a clear oil with a yellow tinge, yields being up to 1.7% by weight. SFE was carried out over a range of temperatures varying from 100 to 400 bar (temperature 45℃) and a range of temperatures varying from 35℃ to 75℃ (pressure 300 bar). These results showed yields generally to increase with pressure but with no significant temperature effect. Maximum yields were similar to those for hydrodistillation i.e. ～ 1.8%. Application of mass transfer theory showed that the bulk of resistance to mass transfer was external with calculated mass transfer coefficients being ～1x10~(-6) m~3m~(-2)s~(-1). The chemical analyses of the two types of oil products showed some differences, with the oil from hydrodistillation showing slightly more of the quality defining esters such as benzyl acetate and benzl benzoate. The SFE products however showed relatively high percentages of eugenols (～24%). It is concluded that there is potential for the use of SFE, technology in producing ylang ylang oils.