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

Abstract

Goals: apply the pulsed flow of steam to a vegetal matrix, made up of orange peels (citrus sinensis), to extract the essential oil contained and to comparatively evaluate the results. Methods: it uses stainless steel experimental equipment and bench scale, based on the intensification of processes, it has accessories and relevant instrumentation, enabled to perform the pulsating flow of steam; that meets the safety requirements. Results: orange essential oil, extracted with a pulsed flow of steam, of very good quality, slightly viscous, faintly yellow, intense pleasant and astringent odor. Using GC-MS, between 22 and 28 component species were identified. The best experimental result achieved was 6.96 % (g-oil/g-DryMatter) when processing a batch of 3.9 kg of vegetable matrix in 18 minutes, with a global composition of: terpenes 98.0%, terpenoids 1.14%, and 0.86% of 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 reveals to be a clean, high-performance, intensified separation technology that can successfully replace continuous steam stripping and other inherent methods of extracting essential oils; carried out in less time and with energy savings. The essential oil obtained, valorization of discarded waste, is a valuable input for different industries.