This study aimed to evaluate the effects of different pretreatment methods on the yield and chemical composition of Nigella sativa L. (i.e., black cumin) cold-pressed oil. Different pretreatment methods used included convection heating, microwave, ultrasound and pulsed electric fields (i.e., PEF); we investigated their effects on key parameters, including oil yield, fatty acid composition, total phenol and flavonoid content, peroxide value, acidity and antioxidant activity. However, no single pretreatment method was found to be better than all others. Instead, ultrasonication and pulsed electric fields (PEF) showed significant advantages. Ultrasonication showed the highest total phenolic content and improved oxidative stability, while PEF improved flavonoid content and antioxidant activity. Therefore, these findings suggest that a combination of several pretreatment options should be considered depending on specific industrial goals related to quality improvement and sustainability. This research also contributes to the existing knowledge on Nigella sativa L. oil processing and provides additional insights for optimizing extraction technique.
Keywords: antioxidants; fatty acids; oil extraction optimization; phenolic content; pulsed electric fields; ultrasonication.