Quality assessment of menthofuran rich essential oil of Mentha piperita (cimap-patra) stored at different temperatures and containers

Abstract

The storage of the menthofuran rich essential oil of Mentha piperita (cv. CIMAP-Patra released by CSIR-CIMAP) is the major problem for its market sustainability. In the present study, the best storage conditions were optimized without degradation in menthofuran content and quality of essential oil. The quality of the essential oil was evaluated in two storage conditions (temperature: 25±2 °C and 4±0.5 °C), three types of storage containers (transparent glass, amber color glass, and aluminium bottles), and six storage periods (3, 6, 9, 12, 15, and 18 months). The results indicated that maximum degradation (52.45%) was reported in the oil sample which was stored in transparent vial at 25 °C. At 4 °C, degradation in menthofuran content was not pronounced irrespective of different containers, however, lowest degradation was reported in amber color bottle. Apart from the menthofuran, pulegone and isomenthone, minor fluctuations in other chemical constituents were recorded, but not in the proper pattern. The refractive index of the essential was not altered with storage condition and time, while optical density was decreased with the storage time. Results suggest that the storage of the menthofuran rich essential oil of Mentha piperita in amber color glass container at 4 °C is the best way to reduce the oxidation and degradation/conversion of menthofuran for a longer period of time.