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41.
Camila da Silva Ana Paula de LimaFernanda de Castilhos Lúcio Cardozo FilhoJ. Vladimir Oliveira 《Biomass & bioenergy》2011,35(1):526-532
This work reports the production of fatty acid ethyl esters (FAEE) from the transesterification of soybean oil in supercritical ethanol in a continuous catalyst-free process using different reactor configurations. Experiments were performed in a microtube reactor with experimental simulation of two reactors operated in series and a reactor with recycle, both configurations at a constant temperature of 573 K, pressure of 20 MPa and oil to ethanol mass ratio of 1:1. Results show that the configurations studied with intermediate separation of glycerol afford higher conversions of vegetable oil to its fatty acid ethyl ester derivatives when compared to the one-step reaction, with relatively low decomposition of fatty acids (<3.0 wt%). 相似文献
42.
Unexploited Thapsia garganica,Orlaya maritima,and Retama raetam Seeds: Potential Sources of Unsaturated Fatty Acid and Natural Antioxidants
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Nizar Tlili Houda Mejri Houda Ben Lajnef Anouer Feriani Abdelhamid Khaldi Nizar Nasri 《Journal of the American Oil Chemists' Society》2015,92(8):1175-1181
Total lipid contents, fatty acid compositions, phenolic profiles and antioxidants activities of seeds from Thapsia garganica, Orlaya maritima, and Retama raetam were investigated. The oil values were more than 26 %, except seeds of R. raetam (ca. 3 %). Unsaturated fatty acids accounted for the majority of the fatty acids (more than 75 %). Oleic and linoleic acid were the predominant fatty acids. Total phenolic compounds (24–104 mg GAE g?1 DR), total flavonoids (4–102 mg QE g?1g DR), total tannins (28–85 mg GAE g?1 DR) and condensed tannins (0.62–131 mg CE g?1 DR) were also determined. The antioxidant activities using different assays were evaluated. The predominant detected classes were the phenolic acids (42–85 %) and the flavonoids (11–48 %). The major phenolic acids were caffeic, trans‐4‐hydroxy‐3‐methoxycinnamic, p‐coumaric, and gallic acid. The predominant flavonoids were quercetin, luteolin, naringin, apigenin, and kaempferol. This study brings attention to the medicinal importance of these species as a source of oil and antioxidant molecules. 相似文献
43.
Ángeles Guinda Mirela Rada Mohamed Benaissa Ibtissam Ourrach José Antonio Cayuela 《Journal of the American Oil Chemists' Society》2015,92(8):1143-1151
The suitability of using visible/near infrared spectroscopy (Vis/NIR), as a rapid and non‐destructive technique for monitoring the quality of argan seeds (Argania spinosa Skeels) was studied. The analyzed parameters were the fatty acid composition of argan seed oil, seed moisture content, seed oil content and oil stability index (OSI). The ratio between major unsaturated and saturated fatty acids (U/S) during the oxidation assay at constant temperature was studied. Values from infrared drying were used as a laboratory reference for the moisture. Argan seed oil content was determined by Soxhlet extraction. A fatty acid analysis was carried out by gas chromatography and the OSI was determined by the Rancimat test. Predictive models of argan seed moisture, ratio U/S and OSI showed good accuracy. Therefore, Vis/NIR measurements can be used for controlling several argan seed quality parameters. This procedure might be of interest to the argan oil industry, which is currently in the process of modernization and expansion. 相似文献
44.
Matthew L. Breeze Elisa Leyva‐Guerrero Grant R. Yeaman Yelena Dudin Ryan Akel Phil Brune Fred Claussen Cecil Dharmasri Jenny Golbach Rong Guo Carl Maxwell Laura Privalle Hilary Rogers Kai Liu Guomin Shan Michele Yarnall Denise Thiede Nancy Gillikin 《Journal of the American Oil Chemists' Society》2015,92(8):1085-1092
Soybean agglutinin (SBA) protein, also known as soybean lectin, is regarded as an anti‐nutrient due to its negative effect on the ability of monogastric animals to gain weight following consumption of raw soybean seed. Historically, SBA has been measured using a time‐consuming and cumbersome hemagglutination procedure. The objective of our research was to obtain a validated methodology that is precise and accurate in the measurement of SBA while allowing minimally equipped laboratories to effectively conduct the analysis, thus our focus was on evaluating an existing commercially available ELISA, an enzyme‐linked‐lectin‐assay (ELLA), and a hybrid ELISA/ELLA. A new ELLA technique that can detect and quantify lectins was chosen and modified specifically for the quantitation of SBA in soybean seed. The proposed ELLA methodology is similar to a standard sandwich ELISA, and uses polyacrylamide‐linked N‐acetylgalactosamine (Gal–NAc–PAA) for a capture phase and the biotinylated version (Gal–NAc–PAA–Biotin) for detection. Based upon the validation data, the ELLA method can precisely and accurately determine soybean lectin levels in soybean seed. The validated ELLA method was used to quantify SBA in nine commercial soybean varieties introduced between 1972 and 2008 and demonstrated that the natural variability of SBA is subject to the effects of genotype and environment. 相似文献
45.
《Food Control》2015
In this study, chlorpyrifos residue levels in field crops of rice, maize and soybean were investigated according to the “Guideline on Pesticide Residue Trials” of China. On the basis of the residual results, human dietary risks were further evaluated. Chlorpyrifos residues of harvest grains were firstly prepared by QuEChERS method and analyzed using Gas Chromatography Tandem Mass Spectrometry (GC–MS/MS). Dietary risks were assessed by a deterministic approach. The median residues in field trials of rice, maize and soybean were 0.617, 0.0227 and 0.0136 mg kg−1, respectively. The highest residues in field trials of rice, maize and soybean were 3.23, 0.114 and 0.102 mg kg−1, respectively. Chronic intake assessment indicated that only 39.0% of acceptable daily intake (ADI, 0–0.01 mg kg bw−1 day−1) was consumed through rice, maize and soybean. The acute hazard indexes (aHI) of adults was 26.1% of acute reference dose (ARfD, 0–0.1 mg kg bw−1) and aHI of children was 63.5% of ARfD in dietary exposure assessment through rice, maize and soybean consumption. Single pathway risk assessment indicated that chlorpyrifos application on field crops in manner of the good agricultural practices didn't pose public health risks. 相似文献
46.
《Food Control》2015
Soybean sauce, a Chinese traditional and daily condiment, is often contaminated by aflatoxin B1. An extract-free immunochromatographic assay was proposed based on fluorescent microspheres probe for the' detection of aflatoxin B1 in soybean sauce. The probe was prepared by coupling fluorescent microspheres with anti-aflatoxin B1 antibody by the 1-ethyl-3(3-dimethylaminopropyl) carbodiimides hydrochloride-mediated method. The background from the soybean sauce sample on strip was eliminated because of the optical property of the probe. The sample without extracting procedure was directly detected by diluting with 10% methanol solution. The visible detection limit for the qualitative analysis of aflatoxin B1 in the proposed method was 2.5 μg/L, which was lower than the maximum level of 5 μg/L set by the Chinese government. The results were well agreed with those obtained by liquid chromatography-mass spectrometry (LC-MS). The method showed satisfactory characteristics, such as rapid detection, easy operation, and high sensitivity, and can thus be applied for the large-scale and on-site screening of soybean sauce contaminated with aflatoxin B1. To our knowledge, this report is the first one on the qualitative detection of aflatoxin B1 in dark colored food samples directly by fluorescent microspheres probe-based immunochromatography. 相似文献
47.
Physical Properties of Soybean Oleogels and Oil Migration Evaluation in Model Praline System
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Huaguang Si Ling-Zhi Cheong Jianhua Huang Xingguo Wang Hong Zhang 《Journal of the American Oil Chemists' Society》2016,93(8):1075-1084
The present study examined the physical properties of soybean oleogels and commercial confectionery filling fats and evaluated the oil migration properties in model praline systems. Soybean oleogels were prepared using different oleogelators namely monoglyceride (MAG oleogels) and a mixture of sorbitan tri‐stearate (STS) with lecithin (50:50) (Lec‐STS oleogels). Both MAG oleogels and Lec‐STS oleogels demonstrated a flat solid fat content (SFC) profile with zero SFC at 40 °C. At low temperature, MAG oleogels and Lec‐STS oleogels demonstrated a non‐flowing gel‐like property due to the ability of the oleogelator to entrap liquid oil. In addition, oleogels also showed thixotropic behavior indicating the possible capability to prevent migration of filling fats to coatings and also good flow ability during pumping though manufacturing equipment. The textural property of oleogels also did not change significantly upon storage indicating good structural stability. When used as in a model praline system, oleogels demonstrated a migration delaying property. 相似文献
48.
Chemical Composition and Physical Properties of High Oleic Safflower Oils (Carthamus tinctorius,Var. CW88-OL and CW99-OL)
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Florencia Salaberría Diana Constenla Amalia A. Carelli María E. Carrín 《Journal of the American Oil Chemists' Society》2016,93(10):1383-1391
Chemical composition and physical properties of CW88‐OL and CW99‐OL cultivars of high oleic safflower seeds and their hexane‐extracted oils were determined. Dry‐based seed composition of CW88‐OL and CW99‐OL was: moisture = 4.29 and 4.23 %, oil = 42.29 and 46.44 %, Crude protein = 20.94 and 16.41 %, neutral detergent fiber = 28.11 and 28.49 %, ash = 1.55 and 2.01 %, phosphorus content = 2033 and 3995 mg/kg, respectively. Major fatty acids in oils were ~78 % oleic (O), ~13 % linoleic (L), ~5 % palmitic (P) and ~2 % stearic (St) acids, for both cultivars. The main triacylglycerols were OOO (~50 %), OOL (~20 %), SOL + OPO (~10 %), and LLP (~5 %). The oil composition of CW88‐OL and CW99‐OL in main minor components was: α‐tocopherol = 582 and 551 mg/kg, total sterols = 3996 and 3362 mg/kg, phospholipids = 22 and 21 mg/kg and wax content = 70 and 74 mg/kg. For both cultivars, density and viscosity of the oils between 25 and 55 °C varied from 903.4 to 912.6 kg/m3 and 63 to 23 mPa.s showing linear and exponential behaviors, respectively. The refractive index was 1.4694. The CIELab color parameters were: 89.69 and 89.53 (L*), ?3.72 and ?3.07 (a*), and 47.28 and 47.78 (b*) (CW88‐OL and CW99‐OL, respectively). Thus, the high oil content of the seeds and nutritional quality of the oil accompanied by low levels of waxes and phospholipids makes the cultivars studied promising for producers and consumers. 相似文献
49.
以200 t/d的豆制品废水处理工程为研究对象,采用气浮-ABR-生物接触氧化组合工艺对其进行处理。结果表明:当进水COD为8 409~14 501 mg/L、BOD5为3 246~6 894 mg/L、NH4+-N为41~111 mg/L、TN为187~365 mg/L、TP为21~39 mg/L时,组合工艺出水水质达到了当地污水处理厂纳管标准。该组合工艺对COD、BOD、TN、TP平均去除率分别达到98.31%、98.30%、91.23%和95.36%。该组合工艺具有工程费用低、运行费用少、耐冲击负荷能力强等优点。 相似文献
50.
Sang-Ik Han Jong-Hyun Chae Kristin Bilyeu J. Grover Shannon Jeong-Dong Lee 《Journal of the American Oil Chemists' Society》2014,91(2):229-234
Soybean [Glycine max (L.) Merr] with increased oleic acid is desirable to improve oxidative stability and functionality of soybean seed oil. Recently, soybean genotypes with high oleic acid (≥70 %) were developed by breeding programs. Efficient and effective identification of high oleic acid soybean genotypes using non-destructive near infrared reflectance (NIR) on whole seeds would greatly enhance progress in breeding programs. The objective of this study was to develop a calibration equation for NIR determination of high oleic acid from single soybean seeds. A total of 600 intact, single F2 seeds were scanned by NIR. Spectral data were collected between 400 and 2,500 nm at 2 nm intervals. The relationship between NIR spectral patterns of each soybean seed and its oleic acid content was examined. The best predicted equations for oleic acid were selected on the basis of minimizing the standard error of cross-validation and increasing the coefficient of determination. Validation demonstrated that the equations for determining total oleic acid and over 50 % oleic acid content had high predictive ability (r 2 = 0.91 and r 2 = 0.99, respectively). To validate the newly developed equation, F2 seeds from a different genetic background were tested. Again, high oleic acid from single soybean seeds was accurately predicted from various genetic backgrounds. Therefore, applying the calibration equations to NIR will be useful to rapidly and efficiently select high oleic acid soybean genotypes in breeding programs. 相似文献