Essential Oil Extraction from Orange and Lemon Peel

Department of Chemical Engineering, Vishwakarma Institute of Technology, Pune, India

^* Hemlata Karne: hemlata.karne@vit.edu

Abstract

The one-third of all food produced for human use is wasted each year which has made food waste a serious problem all around the world. Citrus juice manufacturing factories generate peel leftovers that can account for 50-60% of the weight of the fruit, contributing significantly to food waste. This study investigates the extraction of orange and lemon peel oils using the Soxhlet process and their analysis via gas chromatography. The aim is to identify and quantify key volatile compounds present in these oils, thereby putting the leftover peels to use. Fresh orange and lemon peels were transformed into zest and extracted using Hexane and Ethanol as solvent in a Soxhlet apparatus. Gas chromatography with a specialized column and detector unveiled major volatile compounds, including limonene, linalool, citral. These compounds contribute to the characteristic aroma and potential bioactivity of the oils. Orange peels displayed notably higher limonene content compared to lemon peels. This approach illuminated the chemical composition of the oils, offering opportunities in food, cosmetics, and fragrance industries. Orange peels contained 70-90% limonene, significantly more than lemon peels. The study concluded that peels harbor 28 volatile substances, with limonene responsible for their distinctive citrus scent. In sum, this research underscores the effectiveness of Soxhlet extraction, providing insights into orange and lemon peel oils’ composition using Gas chromatography and applications.