The effects of different drying methods on essential oil content and composition of three genotypes of Rosa damascena Mill.

Rosa damascena Mill. commonly known as rose plant belonging to the family Rosaceae, is an important cultivated aromatic plant. This plant has been cultivated in Iran from many years ago. Due to literature, distillation of rose and obtaining rose water was done in Iran for the first time. In this investigation, the effect of different drying methods (shade, oven 30, 40 and 50°C) on quantity and quality of essential oils of three genotypes of Rosa damascena were studies for the first time. The oils of all samples were obtained by hydro-distillation and analyzed by GC and GC/MS. The results showed no significant difference between the oil yields of fresh and dried petals, but there was significant difference between percentages of main aromatic compounds. The oil of fresh petals had the highest percentage of geraniol and citronellol and the lowest percentage of stearoptens (heavy hydrocarbons). Therefore the best time for extraction of essential oil from Rosa damascena, is right after collection. Comparison of oil content and composition of dried samples showed drying in shade was better and produce higher percentage of oil and aromatic compounds.