Frying quality and stability of low-and ultra-low-linolenic acid soybean oils

To determine effects of very low levels of linolenic acid on frying stabilities of soybean oils, tests were conducted with 2% (low) linolenic acid soybean oil (LLSBO) and 0.8% (ultra-low) linolenic acid soybean oil (ULLSBO) in comparison with cottonseed oil (CSO). Potato chips were fried in the oils for a total of 25 h of oil use. No significant differences were found for either total polar compounds or FFA between samples of LLSBO and ULLSBO; however, CSO had significantly higher percentage of polar compounds and FFA than the soybean oils at all sampling times. Flavor evaluations of fresh and aged (1, 3, 5, and 7 wk at 25°C) potato chips showed some differences between potato chips fried in different oil types. Sensory panel judges reported that potato chips fried in ULLSBO and aged for 3 or 7 wk at 25°C had significantly lower intensities of fishy flavor than did potato chips fried in LLSBO with the same conditions. Potato chips fried in ULLSBO that had been used for 5 h and then aged 7 wk at 25°C had significantly better quality than did potato chips fried 5 h in LLSBO and aged under the same conditions. Hexanal was significantly higher in the 5-h LLSBO sample than in potato chips fried 5 h in ULLSBO. The decrease in linolenic acid from 2 to 0.8% in the oils improved flavor quality and oxidative stability of some of the potato chip samples.     

Mid-Oleic/Ultra Low Linolenic Acid Soybean Oil: A Healthful New Alternative to Hydrogenated Oil for Frying

To determine the frying stability of mid-oleic/ultra low linolenic acid soybean oil (MO/ULLSBO) and the storage stability of food fried in it, tortilla chips were fried in MO/ULLSBO, soybean oil (SBO), hydrogenated SBO (HSBO) and ultra low linolenic SBO (ULLSBO). Intermittent batch frying tests were conducted up to 55 h of frying, and then tortilla chips were aged up to 4 months at 25 °C. Frying oils were analyzed for total polar compounds to determine the frying stability of the oil. Tortilla chips were analyzed for hexanal as an indicator of oxidative deterioration and by sensory analysis using a trained, experienced analytical panel. Results showed no significant differences between the total polar compound levels for MO/ULLSBO and HSBO after 55 h of frying, indicating a similar fry life. However, total polar compound levels for ULLSBO and SBO were significantly higher than for either MO/ULLSBO or HSBO, indicating a lower oil fry life. Hexanal levels in aged tortilla chips fried in SBO were significantly higher than in chips fried in any of the other oils. Tortilla chips fried in MO/ULLSBO and HSBO had significantly lower hexanal levels than in chips fried in ULLSBO. A sensory analysis of rancid flavor intensity showed similar trends to those for hexanal formation. The chips fried in SBO had the highest rancid flavor intensity, with significantly lower hexanal levels in chips fried in HSBO and MO/ULLSBO. Based on these results, MO/ULLSBO not only had a good fry life but also produced oxidatively stable fried food, and therefore would be a healthful alternative to HSBO. Names are necessary to report factually on available data; however, the USDA neither guarantees nor warrants the standard of the product, and the use of the name by the USDA implies no approval of the product to the exclusion of others that may also be suitable.     

Effect of Subcritical Carbon Dioxide Extraction and Bran Stabilization Methods on Rice Bran Oil

The extraction of rice bran oil using the conventional organic solvent‐based Soxhlet method involves hazardous chemicals, whereas supercritical fluid extraction is a costly high‐temperature operating system. The subcritical carbon dioxide Soxhlet (SCDS) system, which operates at a low temperature, was evaluated for the extraction of rice bran oil in this study. In addition, rice bran that had been subjected to steam or hot‐air stabilization were compared with unstabilized rice bran (control). The yields; contents of tocopherols, tocotrienols and oryzanol; fatty acid profiles; and the oxidative stabilities of the extracted rice bran oils were analyzed. The yields using hexane and SCDS extraction were approximately 22 and 13–14.5 %, respectively. However, oil extracted using the SCDS system contained approximately 10 times more oryzanol and tocol compounds and had lower free fatty acid levels and peroxide values compared with hexane‐extracted oil. Overall, SCDS extraction of steamed rice bran represents a promising method to produce premium‐quality rice bran oil.     

Supercritical fluid extraction and characterisation of oil from hazelnut

Hazelnut (Corylus avellana L.) oil was extracted with compressed carbon dioxide in the temperature range of 308—321 K and in the pressure range of 18—23.4 MPa. In addition the influence of the superficial velocity, within a tubular extractor was studied. Physical and chemical characteristics of the oil were obtained. The results including contents of free fatty acids, sterols, triacylglycerols and tocopherols were compared with those obtained when n‐hexane was used as solvent. No significant differences were found when the oils extracted by both methods were analysed. The main fatty acid was the oleic acid (83—85%), followed by linoleic acid (6—8%) and palmitic acid (5—6%). The main triglyceride found in hazelnut oils was the trioleylglycerol (OOO) (63.4—69.6%), followed by the linoleyl‐dioleylglycerol (LOO) (11.6—15.5%) and palmitoyl‐dioleylglycerol (POO) (9.9—10.4%). In terms of sterols, the main component was β‐sitos‐terol (∼83%) followed by campesterol (∼6%). The amount of cholesterol was very low (∼0.2%). The CO₂ extracted oil contained about 17% more tocopherols (458.7 μg/g oil) than the oil extracted by n‐hexane (382.8 μg/g). Oxidative stability was studied by using the induction time determined by the Rancimat method. The oil obtained by supercritical fluid extraction (SFE) was slightly more protected against oxidation (8.7 h for SFE extracted oil and 6.7 h for the hazelnut oil extracted with n‐hexane). Both oils presented high stability index values (7.81 for the oil extracted by n‐hexane and 8.7 for the oil extracted with supercritical CO₂). Oil extracted by supercritical CO₂ was clearer than the one extracted by n‐hexane, showing some refining. Besides, the acidity index was 1.6 for the n‐hexane extracted oil and 0.9 for the oil extracted with supercritical carbon dioxide. The central composite non‐factorial design was used to optimise the extraction conditions, using the Statistica, version 5 software (Statsoft). The best results, in terms of recoveries of hazelnut oil by SFE, were found at 22.5 MPa, 308 K and superficial velocity of 6.0 × 10^—4 ms^—1.     

Extraction and characterization ofDimorphotheca pluvialis seed oil

Dimorphotheca pluvialis is increasingly recognized as an interesting industrial new oilseed crop because it contains up to 60% of the unusual fatty acid dimorphecolic acid (9-hydroxy,10t,12t-18∶2) (DA) for which new applications are being developed. In this paper, the yield, composition and quality are evaluated for dimorphotheca oils (DMO) which were recovered by pressing, conventional solvent extraction and supercritical carbon dioxide extraction (SCE). Mechanical pressing of the seeds required high temperatures and resulted in an oil recovery of only 40%, whereas the extraction protocols yielded more than 95%. Oil recovery by pressing of winged seed was even more difficult than that of unwinged seeds; hence, solvent extraction of winged seeds was preferred. The dark-colored DMO, recovered by expelling or by extraction with organic solvents, needed further refining to remove pigments and gums, whereas the light yellow-colored SCE DMO did not require further refining. SCE oil had a low phospholipid content (11 mg P/kg). Pressed oil (95 mg P/kg) and hexaneor pentane-extracted DMO (200 mgP/kg) had much higher phospholipid contents. Peroxide andp-anisidine values were low for freshly recovered oils, but increased after storage, especially in the SCE oil, due to the low concentration of natural antioxidants in SCE DMO, such as tocopherols. The DA content of the oils recovered by the various techniques showed only minor differences, except that supercritical carbon dioxide had slightly decreased solubilizing power for tri- and di-dimorphecolin as compared to hexane and pentane.     

Effects of Vegetable Oil Composition on Epoxidation Kinetics and Physical Properties

In this article, we investigate the role of triacylglycerol composition on the properties of epoxidized vegetable oils and the kinetics of the epoxidation process under conditions comparable to commercial epoxidation. Commodity soybean oil (24% oleic acid, 50% linoleic acid, and 7% linolenic acid), high‐oleic soybean oil (75% oleic acid, 8% linoleic acid, and 2.5% linolenic acid), and linseed oil (11% oleic acid, 15% linoleic acid, and 64% linolenic acid) were each epoxidized to various extents. Epoxidation rate, viscosity, differential calorimetry, and X‐ray diffraction data are presented for these oils and interpreted in the context of their fatty acid profile (mostly oleic, linoleic, or linolenic). While fully epoxidized soybean oil is widely commercially available and used in an increasing array of industrial applications, information relating to partially epoxidized oils and epoxidized oils of other cultivars is less well known.     

Effect of fatty acid composition of oils on flavor and stability of fried foods

Effects of fatty acid composition of frying oils on intensities of fried-food flavor and off-flavors in potato chips and french-fried potatoes were determined. Commercially processed cottonseed oil (CSO) and high-oleic sunflower oil (HOSUN) were blended to produce oils with 12 to 55% linoleic acid and 16 to 78% oleic acid. Analytical sensory panels evaluated french-fried potatoes and pilot plant-processed potato chips. Initially, both foods prepared in CSO (16% oleic/55% linoleic acid) had the highest intensities of fried-food flavor; however, this positive flavor decreased with decreasing levels of linoleic acid. 2,4-Decadienal in potato chips also decreased with decreasing linoleic acid in the oils. Frying oil stability, measured by total polar compounds (TPC), and oxidative stability of potato chips, measured by volatile compounds, showed that HOSUN (78% oleic acid) produced the lowest levels of TPC and the lowest levels of hexanal and pentanal, indicating greater frying oil stability and oxidative stability of the food. However, fresh potato chips fried in HOSUN had the lowest intensities of fried-food flavor and lowest overall flavor quality. Fried-food flavor intensity was the best indicator of overall flavor quality in fresh potato chips. Volatile compounds, TPC, and oxidative stability index directly varied with increasing oleic acid, and were therefore not directly indicative of flavor quality. No oil analysis predicted flavor stability of aged potato chips. Compositions of 16 to 42% oleic acid and 37 to 55% linoleic acid produced fresh fried-food with moderate fried food flavor intensity, good overall flavor quality, and low to moderate TPC levels (chips only). However, in aged food or food fried in deteriorated oil, compositions of 42 to 63% oleic and 23 to 37% linoleic provided the best flavor stability.     

Bioactive Components of Commercial and Supercritical Carbon Dioxide Processed Wheat Germ Oil

Wheat germ oil (WGO) is a specialty product with a very high nutritional value. The chemical composition of both commercial and pilot scale supercritical carbon dioxide (SC-CO₂) processed WGO was examined. This study showed that methods used for oil extraction and refining did not have a significant effect on the fatty acid composition of the oil. SC-CO₂ extracted oil had a higher tocopherol content than that of commercially hexane extracted oil. The phospholipid content of the SC-CO₂ extracted oil was very low indicating that the SC-CO₂ extraction method could eliminate the degumming step from edible oil refining processes. Although the conventional chemical oil refining technique reduced the tocopherol content of the WGO, it was possible to concentrate tocopherols in WGO by using physical refining methods such as molecular distillation. Published with approval of the Director, Oklahoma Agricultural Experiment Station.     

Comparison of Supercritical Fluid and Hexane Extraction Methods in Extracting Kenaf (<Emphasis Type="Italic">Hibiscus cannabinus</Emphasis>) Seed Oil Lipids

The objective of this study was to investigate and compare fatty acids, tocopherols and sterols of kenaf seed oil extracted by supercritical carbon dioxide and traditional solvent methods. Fatty acids, tocopherols and sterols were determined in the extracted oils as functions of the pressure (400 bar, 600 bar), temperature (40 °C, 80 °C) and CO₂ flow rate (25 g/min) using a 1-L extraction vessel. Gas chromatography was used to characterize fatty acids and sterols of the obtained oils while tocopherols were quantified by HPLC. No differences were found in the fatty acid compositions of the various oil extracts and the main components were found to be linoleic (38%), oleic (35%), palmitic (20%) and stearic acid (3%). Extraction of tocopherols using high pressure (600 bar/40 °C, 600 bar/80 °C) gave higher total tocopherols (88.20 and 85.57 mg/100 g oil, respectively) when compared with hexane extraction which gave yield of 62.38 mg/100 g oil. Extraction of kenaf seed oil using supercritical fluid extraction at high temperature (80 °C) gave higher amounts of sterols when compared with hexane extraction.     

Effects of frying oil composition on potato chip stability

Potato chips were fried in six canola (low-erucic acid rape-seed) oils under pilot-plant process settings that represented commercial conditions. Oil samples included an unmodified canola oil and oils with fatty acid compositions modified by mutation breeding or hydrogenation. Chips were fried for a 2-d, 18-h cycle for each oil. Chips and oil were sampled periodically for sensory, gas-chromatographic volatiles and chemical analyses. Unmodified canola oil produced chips with lower flavor stability and oxidative stability than the other oils. The hydrogenated oil imparted a typical hydrogenation flavor to the chips that slightly affected overall quality. the modified canola oil (IMC 129) with the highest oleic acid level (78%) had the lowest content of total polar compounds and the lowest total volatile compounds at most of the storage times; however, the sensory quality of the potato chip was only fair. The potato chip with the best flavor stability was fried in a modified/blended oil (IMC 01-4.5/129) with 68% oleic acid, 20% linoleic acid and 3% linolenic acid.     

Kinetics of supercritical carbon dioxide extraction of borage and evening primrose seed oil

In the present work, high‐pressure extraction of borage (Borago officinalis L.) and evening primrose (Oenothera biennis L.) seed oil, containing the valuable γ‐linolenic acid (GLA), has been investigated. Extraction was performed with supercritical carbon dioxide on a semi‐continuous flow apparatus at pressures of 200 and 300 bar, and at temperatures of 40 and 60 °C. A constant flow rate of carbon dioxide in the range from 0.17 to 0.20 kg/h was maintained during extraction. The extraction yields obtained using dense CO₂ were similar to those obtained with conventional extraction using hexane as solvent. The composition of extracted crude oil was determined by GC analysis. The best results were obtained at 300 bar and 40 °C for both seed types extracted, where the quality of oil was highest with regard to GLA content. The evening primrose seed oil extracted with supercritical fluid extraction was particularly rich in unsaturated fatty acids: up to 89.7 wt‐% of total free fatty acids in the oil. The dynamic behavior of the extraction runs was analyzed using two mathematical models for describing the constant rate period and the subsequent falling rate period. Based on the experimental data, external mass transfer coefficients, diffusion coefficients and diffusivity in solid phase were estimated. Results showed good agreement between calculated and experimental data.     

Performance of Regular and Modified Canola and Soybean Oils in Rotational Frying

Canola and soybean oils both regular and with modified fatty acid compositions by genetic modifications and hydrogenation were compared for frying performance. The frying was conducted at 185 ± 5 °C for up to 12 days where French fries, battered chicken and fish sticks were fried in succession. Modified canola oils, with reduced levels of linolenic acid, accumulated significantly lower amounts of polar components compared to the other tested oils. Canola oils generally displayed lower amounts of oligomers in their polar fraction. Higher rates of free fatty acids formation were observed for the hydrogenated oils compared to the other oils, with canola frying shortening showing the highest amount at the end of the frying period. The half-life of tocopherols for both regular and modified soybean oils was 1–2 days compared to 6 days observed for high-oleic low-linolenic canola oil. The highest anisidine values were observed for soybean oil with the maximum reached on the 10th day of frying. Canola and soybean frying shortenings exhibited a faster rate of color formation at any of the frying times. The high-oleic low-linolenic canola oil exhibited the greatest frying stability as assessed by polar components, oligomers and non-volatile carbonyl components formation. Moreover, food fried in the high-oleic low-linolenic canola oil obtained the best scores in the sensory acceptance assessment.     

Frying stability of soybean and canola oils with modified fatty acid compositions

Pilot plant-processed samples of soybean and canola (lowerucic acid rapeseed) oil with fatty acid compositions modified by mutation breeding and/or hydrogenation were evaluated for frying stability. Linolenic acid contents were 6.2% for standard soybean oil, 3.7% for low-linolenic soybean oil and 0.4% for the hydrogenated low-linolenic soybean oil. The linolenic acid contents were 10.1% for standard canola oil, 1.7% for canola modified by breeding and 0.8% and 0.6% for oils modified by breeding and hydrogenation. All modified oils had significantly (P<0.05) less room odor intensity after initial heating tests at 190°C than the standard oils, as judged by a sensory panel. Panelists also judged standard oils to have significantly higher intensities for fishy, burnt, rubbery, smoky and acrid odors than the modified oils. Free fatty acids, polar compounds and foam heights during frying were significantly (P<0.05) less in the low-linolenic soy and canola oils than the corresponding unmodified oils after 5 h of frying. The flavor quality of french-fried potatoes was significantly (P<0.05) better for potatoes fried in modified oils than those fried in standard oils. The potatoes fried in standard canola oil were described by the sensory panel as fishy.     

Performance evaluation of hexane-extracted oils from genetically modified soybeans

Soybeans produced by induced mutation breeding and hybridization were cracked, flaked and hexane-extracted, and the recovered crude oils were processed to finished edible oils by laboratory simulations of commercial oil-processing procedures. Three lines yielded oils containing 1.7, 1.9 and 2.5% linolenic acid. These low-linolenic acid oils were evaluated along with oil extracted from the cultivar Hardin, grown at the same time and location, and they were processed at the same time. The oil from Hardin contained 6.5% linolenic acid. Low-linolenic acid oils showed improved flavor stability in accelerated storage tests after 8 d in the dark at 60°C and after 8h at 7500 lux at 30°C, conditions generally considered in stress testing. Room odor testing indicated that the low-linolenic oils showed significantly lower fishy odor after 1 h at 190°C and lower acrid/pungent odor after 5 h. Potatoes were fried in the oils at 190°C after 5, 10 and 15 h of use. Overall flavor quality of the potatoes fried in the low-linolenic oils was good and significantly better after all time periods than that of potatoes fried in the standard oil. No fishy flavors were perceived with potatoes fried in the low-linolenic oils. Total volatile and polar compound content of all heated oils increased with frying hours, with no significant differences observed. After 15 h of frying, the free fatty acid content in all oils remained below 0.3%. Lowering the linolenic acid content of soybean oil by breeding was particularly beneficial for improved oil quality during cooking and frying. Flavor quality of fried foods was enhanced with these low-linolenic acid oils.     

Frying performance of genetically modified canola oils

The frying performance of low linolenic and high oleic canola oils was compared to regular and hydrogenated canola oils. The antifoaming agent dimethylpolysiloxane (2 ppm) was added to all frying oils. Potato chips were fried in the four oils over a 5-d period for a total of 40 h of frying. Oil samples were collected each day and analyzed for conjugated dienoic acids, free fatty acids, polymers, oxidation products, and polar components. Polar components were determined by the gravimetric method and by thin-layer chromatography with flame-ionization detection. The initial quality of the four oils was similar except in the amount of tocopherols present. All oils deteriorated after 5 d of frying but differences were not as anticipated, possibly as a result of observed differences in tocopherol levels.     

Quantitative extraction of pecan oil from small samples with supercritical carbon dioxide

A procedure to determine total oil content of pecan was developed for samples weighing 500 and 10 mg by supercritical fluid extraction (SFE) with carbon dioxide as the extraction solvent, and chilled hexane as the trapping solvent. Fatty acid methyl esters (FAMEs) were prepared from the total lipid fraction by using either an aliquot (500 mg starting weight) or the entire extract (10 mg starting weight). Total oil content obtained for either sample size with SFE was similar to that obtained with an organic solvent extraction technique. The fatty acid composition for the total lipid fraction of oils extracted with SFE was the same as for oils extracted with organic solvents, and oil composition did not change during SFE. Both oil yield and fatty acid composition were similar to those reported previously for pecan. Samples could be extracted and placed into FAME-derivatizing reagents in one day, and fatty acid composition of the total lipid fraction could be determined by gas-liquid chromatography the next day. The procedure, as demonstrated for pecan, should be suitable for other oilseeds, especially those containing low amounts of water.     

Method for characterization of triacylglycerols and fat-soluble vitamins in edible oils and fats by supercritical fluid chromatography

This study demonstrates the usefulness of capillary supercritical fluid chromatography (SFC) for the characterization of triacylglycerols of edible oils and fats. Triacylglycerols were separated according to the acyl carbon number and the degree of unsaturation on a 25% cyanopropyl/25% phenyl/50% methylpolysiloxane stationary phase. Valuable information concerning the triacylglycerol composition of berry oils was obtained, despite the overlapping of certain triacylglycerol peaks. Simultaneous analysis of fat-soluble vitamins and triacylglycerols is not practical by capillary SFC with flame-ionization detection because of the low concentration of naturally-occurring fat-soluble vitamins in edible oils. Therefore, higher loading of the sample, which led to overloading of triacylglycerols, was required to get reasonable peaks for fat-soluble vitamins. The method was applied to the characterization of triacylglycerols and tocopherols in sea buckthorn pulp and seed oil, and cloudberry seed oil without any sample purification prior to SFC. In addition, the stationary phase proved useful for separating the more complex mixtures of triacylglycerols found in milk fat and in fish oil.     

Chemical and physical analyses and sensory evaluation of six deep-frying oils

The performance of three high-oleic canola oils with different levels of linolenic acid [low-linolenic canola (LLC), medium-linolenic canola (MLC), and high-linolenic canola (HLC)], a medium-high-oleic sunflower oil, a commercial palm olein and a commercial, partially hydrogenated canola oil, was monitored by chemical and physical analyses and sensory evaluation during two 80-h deep-frying trials with potato chips. Linolenic acid content was a critical factor in the deep-frying performance of the high-oleic canola oils and was inversely related to both the sensory ranking of the food fried in the oils and the oxidative stability of the oils (as measured by color index, free fatty acid content, and total polar compounds). LLC and sunflower oil were ranked the best of the six oils in sensory evaluation, although LLC performed significantly better than sunflower oil in color index, free fatty acid content, and total polar compounds. MLC was as good as palm olein in sensory evaluation, but was better than palm olein in oxidative stability. Partially hydrogenated canola oil received the lowest scores in sensory evaluation. High-oleic canola oil (Monola) with 2.5% linolenic acid was found to be very well suited for deep frying.     

Tunisian Pistacia atlantica Desf. Extraction Process: Impact on Chemical and Nutritional Characteristics

Plant materials have been used in different fields such as therapeutics, cosmetics, and energy for ages. Several studies have investigated seeds, whether common or not, in order to ensure a better valuation of natural resources. Among these, Pistacia atlantica Desf. has been the subject of several works on its characterization and valorization. Among the current trends in sustainable development and environmental protection, valorizing natural wild plants via green chemistry has become prevalent. One of these plants, Pistacia atlantica Desf., is a tree that grows in arid and semi-arid areas, notably in Tunisia, and produces seeds rich in oil. In this study extracting the oil from its seeds is tried by three methods (supercritical carbon dioxide (CO₂), pressure, and hexane), and the efficiency of these extraction processes is compared in order to obtain the best yield and maximize its valorization in a variety of industrial fields. The obtained oil is found to be rich in polyunsaturated fatty acids, namely linoleic and oleic acids, with a similar acidic composition among all extraction methods. The tocopherol composition of the oil is determined using high performance liquid chromatography. The total polyphenol content is determined using the Folin-Ciocalteu colorimetric analysis method. The results show that the seed oil of Pistacia atlantica Desf. extracted by supercritical CO₂ gives the highest extraction yield (25%) and the lowest acidity and peroxide values with a high degree of oxidation at 232 and 270 nm. This method also gives the highest content of alpha, gamma, and delta tocopherol as well as total phenolic content compared to the other extraction methods. The composition of chlorophylls and carotenes in the seed oil of Pistacia atlantica Desf. is determined. Besides, the analysis of the sterol composition reveals that β-sitosterol is still prevailing. Among all the tested extracts, the supercritical CO₂ extract demonstrates the best antioxidant performance against the tested radicals. The oil extracted by supercritical carbon dioxide (CO₂) is of a higher quality compared to that extracted by pressure and by hexane. Practical applications : The Pistacia atlantica Desf. oil exhibits interesting physicochemical and biological characteristics. The type of extraction affects the quality of the major and minor components in the seeds. However, the supercritical CO₂ method produces a better oil quality with the presence of antioxidants such as tocopherols and polyphenols. In fact, it is found that the oil extracted by the three methods has an important sterolic profile with the predominance of β-sitosterol. According to the classification of vegetable oils, unsaturated fatty acids of atlas pistachio oil can be categorized as oleo linoleic oil, which enhances its nutritional value. Having these characteristics, the use of this oil can be considered in agrifood products.     

Extraction and Characterization of Seed Oil from Naturally Grown Chinese Tallow Trees

Seeds were collected from locally and naturally grown Chinese tallow trees (CTT) and characterized for general physical and chemical properties and fatty acid composition of the lipids. The effects of four different solvents (petroleum ether, hexane, diethyl ether, and 95 % ethanol) and two extraction methods (supercritical carbon dioxide (SC-CO₂) and conventional Soxhlet) on the properties of the CTT seed oil, including Chinese vegetable tallow (CVT) and stillingia oil (SO), were also investigated. In general, the yields of CVT and SO did not vary based on solvent for Soxhlet extraction and solvent-free SC-CO₂ extraction, except that the yield of CVT from SC-CO₂ extraction was substantially lower. Nevertheless, the CTT seed oil, extracted by SC-CO₂ displayed better quality than those extracted by Soxhlet extraction in terms of color, residual precipitation, and acid value of the oils. The pretreatment of CTT seed by 3 % aqueous sodium bicarbonate solution likely promoted the hydrolysis of triglyceride and caused the high acid value in the CVT samples. The iodine value at around 180 indicated that the SO is a highly unsaturated drying oil. Palmitic (76 %) and oleic (23 %) are two dominant fatty acids in CVT while linolenic (43 %), linoleic (31 %), and oleic (13 %) are the dominant fatty acids in SO.