Ohmic-assisted hydrodistillation as an effective approach for high-yield citrus essential oil extraction

In recent years, the integration of electrical heating techniques into conventional distillation systems has garnered considerable interest in the distillation of essential oils. One such approach is ohmic-assisted hydrodistillation (OAHD). This technology integrates ohmic heating and hydrodistillation (HD). This study examines the impact of various raw materials, including fresh citrus peel, oven-dried citrus peel, and sun-dried citrus peel, on OAHD and HD. Parameters evaluated included extraction time, oil yield, energy consumption, chemical composition, and sensory characteristics. The extraction time of OAHD was significantly faster than HD, with a boiling point of 8.10–9.35 min compared to 27.83–31.99 min in HD. The yield of essential oils produced by OAHD was 8.8-14.9% compared to HD, 5.8–11.9%. Energy consumption was also lower with OAHD, indicating higher process efficiency. D-limonene was identified as the predominant compound across all treatments. Sensory evaluation revealed that essential oils from fresh peels had a fresh, sweet–sour aroma, while those from dried peels exhibited stronger herbal and woody notes. Overall, OAHD emerges as an excellent method with significant implications for process intensification in the extraction process of mandarin citrus essential oils.