Qualitative Variations of Lavandin Essential Oil under Various Storage Conditions

Abstract

Essential oils (EOs) are widely used in products related to human health. Thus, providing an optimum storage condition to preserve their quality and stability is very important. The effects of various duration and storage conditions on lavandin (Lavandula × intermedia L.) EO was investigated as used the raw material of aromatherapy and health products. The watery and dehydrated samples were stored in laboratory temperature (24±2°C), refrigerator (+4°C) and freezer (-18°C) for 100 and 200 days. Also, a sample of watery and a sample of dehydrated EO were exposed to air at laboratory temperature. GC/FID-MS analyses were performed to determine the variations in the components of the stored EOs. Linalool (39.49-45.81 %) was the major component in all samples. The other main components were camphor (9.95-14.68 %), borneol (8.77-12.45 %), 4-terpineol (6.12-9.51 %), 1,8-cineole (1.27-6.79 %), linalyl acetate (3.45-4.02 %), cis-linalool oxide (0.30-4.39 %) and trans-linalool oxide (0.19-4.03 %). Due to the evaporation and conversion processes, most of the components had a decreasing or increasing tendency during the storage period. Also, components such as α-pinene, camphene, β-myrcene, γ-terpinene, α-terpinolene, trans-sabinene hydrate and D-carvone disappeared during the oxidation process. Based on observations, storage time and temperature, water presence, atmospheric gases and possibly light had destructive effects on the concentration of lavandin EO components. It can be estimated that the molecular weight, molecular structure and boiling point caused the oscillation of lavandin EO constituents under various storage conditions. According to the findings, the best storage conditions for lavandin EO were low temperature and the absence of atmospheric gases and water.