EFFECT OF DIFFERENT DRYING AND STORAGE METHODS ON THE QUALITY OF SOME MEDICINAL PLANTS: I- EFFECT OF DIFFERENT DRYING AND STORAGE METHODS ON THE QUALITY OF LEMONGRASS OIL (Cymbopogon citratus).

This study was carried out on lemongrass in Agriculture Research Station, Department of Vegetable and Floriculture, Faculty of Agriculture, Mansoura University in two successive seasons (June 1993 and 1994), for evaluation of the effect of different drying, storage methods and periods on properties of lemongrass plant. The essential oil percentage was determined in addition to its physical and chemical properties. The highest percentage of essential oil was obtained from drying plant in shade and storing in cotton bags for three months (1.85%), while the lowest one was obtained from drying in sun and storing in plastic bags for 12 months (0.42%). The lowest values of acid number (5.87) was observed in the drug, dried in shade and stored in cotton bags, while the highest value (11.8) was obtained from the plant which dried in oven and stored in plastic bags for 12 months. The lowest value of refractive index (1.37) detected was when the plant dried in shade and stored in cotton bags for three months, While the highest value (1.48) was noticed in the drug dried in oven and stored in plastic bags for 12 months. The highest percentage of citral (the main component of essential oil) was obtained (67.7%) by shade drying and storing in cotton bags for three months, while the lowest (52.9%) was obtained by oven drying and storing in plastic bags for 12 months.