Storage of Essential Oils: Influence of Presence of Water for Short Periods on the Composition of Major Constituents of the Essential Oils of Four Economically Important Aromatic Crops

Appropriate storage of essential oils is important to retain their quality until their marketing by the producers or their utilization in flavour and fragrance consumer products by the industry. Water, air, light are reported to influence the composition of essential oils during prolonged storage, if they are improperly stored. In India, aromatic crops are cultivated largely by small and marginal farmers with limited resources and traders often report that farmers bring essential oils mixed with different proportions of distillation water. A laboratory experiment was therefore, conducted to investigate the influence of presence of varying quantities of water for short storage periods, on the composition of major chemical constituents of the essential oils of four economically important aromatic crops namely, palmarosa {Cymbopogon martinii (Roxb.) Wats. var. motia Burk., Family: Poaceae}, lemongrass {Cymbopogon flexuosus (Nees ex Steud) Wats., Family: Poaceae}, citronella (Cymbopogon winterianus Jowitt., Family: Poaceae) and lemon-scented gum (Eucalyptus citriodora Hook., Family: Myrtaceae). Principal chemical constituents of the essential oils of palmarosa (geraniol: 80.1 – 84.2 %, geranyl acetate: 10.3 – 11.3 %, linalool: 3.4 – 3.5 %), lemongrass (citral: 73.3 – 75.9 %, geraniol: 5.3 – 5.6 %), citronella (citronellal: 35.1 – 37.9 %, citronellol: 18.0 – 19.0 %, geraniol: 16.8 – 17.5 %, linalool: 1.4 – 1.5 %) and lemon-scented gum (citronellal: 73.9 – 76.3 %, isopulegol: 4.9–6.8 %, citronellol: 5.0 – 5.5 %, linalool: 1.0 – 1.3 %) did not significantly differ during the short storage periods of 1 to 15 days in the presence of 10 % or 20 % (by volume of the essential oils) of water.