Effects of Pulsed Electric Field on Oil Extraction Rate and Tocopherol in Peony Seeds

Abstract

Featured Application: Pulsed electric field (PEF) technology has been extensively investigated in the realm of plant oil extraction, yielding positive outcomes for various oils such as olive, rapeseed, and sunflower. Consensus has been reached that PEF can undeniably enhance oil yield. Given the low yield, yet high nutritional and economic value of peony seeds, it is imperative to improve their oil production; however, limited research exists on utilizing PEF to enhance peony seed oil yield. Conducting relevant studies will facilitate the application and popularization of PEF technology and equipment in the domain of peony seed oil extraction. Peony seed oil, known for its high nutritional value and low production yield, has become a crucial component in high-quality health products. Consequently, enhancing the extraction efficiency of peony seed oil has become an industry objective. Pulse electric field (PEF) technology, as a non-thermal extraction method, has shown promising advancements in improving plant oil yield by enhancing cell permeability. In this study, we designed a static parallel plate PEF treatment unit to process peony seed particles. By manipulating pulse voltage parameters, we investigated the effects of particle size and PEF strength on the oil yield. We also analyzed and evaluated tocopherol in the oil before and after treatment. The results demonstrated that PEF significantly increased the oil yield. Both treated and control groups exhibited gradually increased oil yields with decreasing particle size until reaching saturation at a certain particle size. Increasing voltage frequency did not have a significant impact on the oil yield; however, increasing voltage amplitude resulted in an optimal point for maximum oil yield. Analysis of oil composition indicated that PEF appropriately increased tocopherol content. These findings provide a foundation for further optimization of PEF parameters to assist in extracting peony seed oil and facilitate its industrial application.