The influence of pulsed electric fields and microwave pretreatments on some selected physicochemical properties of oil extracted from black cumin seed

Abstract

Application of novel technologies such as microwave and pulsed electric fields (PEF) might increase the speed and efficiency of oil extraction. In the present research, PEF (3.25 kV/cm electric field intensity and 30 pulse number) and microwave (540 W for 180 s) pretreatments were used to study the process of oil extraction from black cumin (Nigella sativa) seeds. After applying the selected pretreatments, the oil of seeds was extracted with the use of a screw press and the extraction efficiency, refractive index, oil density, color index, oxidative stability, and chemical components of oil and protein of meal were evaluated. The achieved results expressed that PEF and microwave pretreatments increased the oil extraction efficiency and its oxidative stability. Different pretreatments didn't have any significant influence on the refractive index of black cumin seed oil (p>.05). When microwave and PEF were used, the oil density showed an enhancement as the following: 1.51% and 0.96%, respectively in comparison with the samples with no pretreatments. Evaluation of the extracted oils, using GC/MS analysis indicated that thymoquinone was the dominant phenolic component in the black cumin oil. Finally, the SEM analysis revealed that microwave and PEF can be useful in the extraction of oil from black cumin seeds since these treatments damaged cell walls and facilitated the oil extraction process.

Optimized extraction and quality evaluation of Niger seed oil via microwave‐pulsed electric field pretreatments

“…Further decrease in oil extraction efficiency at higher microwave irradiation time and PEF intensity could be explained by more destruction of internal structures of cells and blocking of oil extraction pores/routes. Bakhshabadi et al () demonstrated that application of high PEF intensity may lead to a decrease in oil extraction efficiency which were in agreement with the obtained results of the current study. Increase in screw press rotational speed led to a decrease in oil extraction efficiency possibly due to a reduction in applied pressure onto the seeds which is similar to the data reported by some other researcher groups (Deli, Farah Masturah, Tajul Aris, & Wan Nadiah, ; Evon, Vandenbossche, Pontalier, & Rigal, ).…”

“…Further decrease in oil extraction efficiency at higher microwave irradiation time and PEF intensity could be explained by more destruction of internal structures of cells and blocking of oil extraction pores/routes. Bakhshabadi et al (2018) demonstrated that application of high PEF intensity may lead to a decrease in oil extraction efficiency which were in agreement with the obtained results of the current study. Increase in screw press rotational TA B L E 2 Analysis of variance (ANOVA) for determined parameters in oil extraction by microwave-PEF pretreatment…”

“…PEF processing includes short-term pulses (µs) with a high intensity in a strong electrical field on food materials. The application of PEF due to enhancements of cell permeation might increase oil extraction efficiency and there have been some reports on the positive effects of this process on the qualitative and sensory properties of the extracted oil (Bakhshabadi, Mirzaei, Ghodsvali, Jafari, & Ziaiifar, 2018;Boussetta, Soichi, Lanoiselle, & Vorobiev, 2014;Sarkis, Boussetta, Tessaro, Marczak, & Vorobiev, 2015). For instance, PEF has been applied for fat/oil production from microalgae (La et al, 2016).…”

Optimization of producing oil and meal from canola seeds using microwave − pulsed electric field pretreatment

“…Eventually, they stated that it's possible to use this process in extracting oil from sunflower seeds in higher scales (Shorstkii et al, 2017). Zeng et al (2010) and Bakhshabadi et al (2018) were some other researchers who had used PEF for oil extraction (Zeng et al, 2010;Bakhshabadi et al, 2018). Researchers showed that application of combined pretreatment of hydrothermal-MW leads to increase in the efficiency of oil extraction (Cortese et al, 2019).…”

Efficient extraction of black cumin ( Nigella sativa L.) seed oil containing thymol, using liquefied dimethyl ether (DME)

“…Several methods exist for the extraction of the oil from the raw seeds (Babar et al, 2018). These include the use of: petroleum ether (Mai Lea et al, 2004), hexane (Mai Lea et al, 2004), ethanol (Hosseinzadeh, Tafaghodi, Jalal, & Taghiabad, 2013), hydrodistillation (Benkaci-Ali, Baaliouamer, Meklati, & Chemat, 2007), electric fields/microwave (Bakhshabadi et al, 2017a(Bakhshabadi et al, , 2017b, supercritical carbon dioxide (sCO 2 ) (Machmudah, Shiramizu, Goto, Sasaki, & Hirose, 2005), with cold pressing however, being the most popular (Cheikh-Rouhou et al, 2007). Each of these models has their characteristic advantages but several drawbacks exist, including: the use of toxic and hazardous solvents, low extraction yields, application of heat in some cases which can compromise the integrity of extracts, the use of costly apparatus and time consuming methodologies (Kiralan, Ozkan, Bayrak, & Ramadan, 2014;Soto, Chamy, & Zuniga, 2007).…”