The pulsating flow of steam: eco-friendly technology for extracting essential oil from Citrus sinensis Osbeck peels

Abstract

Objective: To extract the essential oil of orange peels (Citrus sinensis) with the pulsed steam flow to compare the results to other inherent methods. Methodology: A bench scale stainless steel experimental unit was used, based on the intensification of processes, with accessories and pertinent instrumentation, enabled to perform the pulsed steam flow; it complies with the operational safety requirements. Results: The orange essential oil, extracted with the pulsed steam flow was of good quality, slightly viscous, weakly yellow, with a pleasant intense odor and astringent. Between 22 and 28 component species were identified by GC-MS. The best experimental result achieved was 6.96 % (g-oil/g-dry matter) when processing a 3.9 kg batch of plant matrix in 18 minutes, with an overall composition of 98.0% terpenes, 1.14% terpenoids, and 0.86% oxygenated compounds; the most relevant components are: limonene 92.64 %, β-myrcene 3.3%, α-pinene 0.95%, β-linalool 0.74%, remaining identified species 2.33 % and unidentified species 0.04%. Conclusions: pulsed steam flow is an intensified, clean and high-performance separation technology, which can successfully replace continuous steam flow entrainment hydro extraction and other inherent methods of essential oil extraction; performed in less time and with energy savings.