VEGETABLE OIL-BASED FUELS, ADDITIVES AND COPRODUCTS
Location: Bio-oils Research Unit
Title: Composition and physical properties of arugula, shepherd's purse, and upland cress oils
Submitted to: European Journal of Lipid Science and Technology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: April 15, 2010
Publication Date: July 15, 2010
Citation: Moser, B.R., Moser, J.K., Shah, S.N., Vaughn, S.F. 2010. Composition and physical properties of arugula, shepherd's purse, and upland cress oils. European Journal of Lipid Science and Technology. 112:734-740.
Interpretive Summary: This research demonstrated that arugula, shepherd’s purse, and upland cress oils, three new vegetable oils, are attractive alternatives to commodity vegetable oils for important industrial applications. Commodity vegetable oils are expensive and have numerous competing applications, so the search for more economically advantageous alternatives is important. The objectives of this study were to determine the chemical compositions of these oils and to measure a number of important physical properties in an effort to ascertain their potential as chemical feedstocks for important industrial materials. It was discovered that arugula, shepherd’s purse, and upland cress oils, in many respects, are superior to soybean oil. These results are important to the chemical and biodiesel industries because these oils may serve to augment the supply of bio-based starting materials for the production of essential industrial products. This research may, ultimately, improve market penetration and public perception of domestically produced agricultural materials, such as biodiesel, lubricants, surfactants, and greases, thus affording greater national independence from imported petroleum-based products.
The fatty acid, tocopherol and phytosterol profiles of arugula [AO; Eruca vesicaria (L.) Cav. subsp. sativa (Mill.) Thell.], upland cress [UCO; Barbarea verna (Mill.) Asch.], and shepherd's purse [SPO; Capsella bursa-pastoris (L.) Medik.] oils are reported, along with their physical properties. The tocopherol content of SPO (769 ppm) was higher than detected in AO (656 ppm) and UCO (430 ppm). UCO contained a higher concentration of phytosterols (8.47 mg/g) than SPO (7.19 mg/g) and AO (6.60 mg/g). The oil contents of AO, SPO, and UCO were 27.0, 26.6, and 24.2 wt %. The acid values of AO (0.54 mg KOH/g) and UCO (0.32 mg KOH/g) were lower than obtained for SPO (3.19 mg KOH/g). The principle fatty acid in AO and UCO was erucic acid (41.7 and 36.8 wt %), whereas SPO contained primarily linolenic (32.4 wt %) and linoleic (20.5 wt %) acids. AO and UCO were more stable to oxidation than SPO, as indicated by induction periods (110 deg C; EN 14112) of 16.5, 7.9, and 2.2 h. SPO exhibited lower kinematic viscosity and higher VI than AO and UCO. UCO displayed the lowest pour point (-29 deg C), followed by AO (-22 deg C) and SPO (-14 deg C).