Variation in Scent Compounds of Oil-Bearing Rose (Rosa damascena Mill.) Produced by Headspace Solid Phase Microextraction, Hydrodistillation and Solvent Extraction

In this research, rose oil and rose water were hydro-distilled from the fresh oil-bearing rose flowers (Rosa damascena Mill.) using Clevenger-type apparatus. Rose concretes were extracted from the fresh rose flowers by using non-polar solvents, e.g. diethyl ether, petroleum ether, cyclo-hexane, chloroform and n-hexane, and subsequently by evaporation of the solvents under vacuum. Absolutes were produced from the concretes with ethyl alcohol extraction at -20°C, leaving behind the wax and other paraffinic substances. Scent compounds of all these products detected by gas chromatography (GC-FID/GC-MS) were compared with the natural scent compounds of fresh rose flower detected by using headspace solid phase microextraction (HS-SPME) with carboxen/polydimethylsiloxane (CAR/PDMS) fiber. A total of 46 compounds analysis were identified by HS-SPME-GC-MS in the fresh flower, and a total of 15 compounds were identified by GC-MS in the hydrodistilled rose oil. While main compounds in rose oil were geraniol (35.4%), citronellol (31.6%), and nerol (15.3%), major compound in fresh rose flower, rose water and residue water was phenylethyl alcohol (43.2, 35.6 and 98.2%, respectively). While the highest concrete yield (0.7%) was obtained from diethyl ether extraction, the highest absolute yield (70.9%) was obtained from the n-hexane concrete. The diethyl ether concrete gave the highest productivity of absolute, as 249.7 kg of fresh rose flowers was needed to produce 1 kg of absolute.