Effect of Drying Methods and Drying Days on Essential Oil Content and Physicochemical Properties of Basil (<i>Ocimumbasilicum</i>) Varieties in Ethiopia

Abstract

Basil (Ocimumbasilicum L.) is an herbaceous annual aromatic herb that belongs to the Lamiaceae family. This study aimed to analyze the essential oil content and physicochemical properties of basil varieties stored under different drying methods and dried on different drying days. The fresh leaf of basil varieties was collected from the Wondo Genet Agriculture research center experimental field and subjected to open sun and shade drying methods and four drying days (0,5, 10, and 15). The sample was subjected to oven and hydrodistillation methods on each four particular drying days. The obtained essential oils were analyzed for physical properties (specific gravity and refractive index) and chemical composition using GC-MSD. As shown in the result of all-cause drying methods and drying days significantly affect the essential oil content and physicochemical properties of Basil Variety. In the case of Variety, Basil 02 has a high essential oil content than Basil 05 in the chemical composition, and different chemical compositions exist in both. In the case of drying methods, the sample dried under the shade is higher than in the open sun in essential oil content and physicochemical properties. In the case of different drying days, as the drying days increase, the essential oil content is significantly affected. The essential oil content and physicochemical properties of essential oil decrease as drying days increase for both basil varieties. Drying affects the chemical composition of the two variables, which means, as in the cause of open sun drying, affects the chemical composition more than shade drying as the drying days increase, and the chemical composition decrease. Therefore, this study provides evidence that drying herbs on different drying days and under drying conditions affect the essential oil content and physicochemical properties of essential oil.