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1.
The objective of this research was to evaluate the effect of high‐intensity ultrasound (HIU) and crystallization temperature (Tc) on the crystallization behavior, melting profile, and elasticity of a soft stearin fraction of high‐stearic high‐oleic sunflower oil. Results showed that HIU can be used to induce and increase the rate of crystallization of the soft stearin with significantly higher SFC values obtained in the sonicated samples, especially at higher Tc. SFC values were fitted using the Avrami model, and higher kn and lower n values were obtained when samples were crystallized with sonication, suggesting that sonicated samples crystallized faster and through an instantaneous nucleation mechanism. In addition, the crystal morphology, melting behavior, and viscoelasticity were significantly affected by sonication.  相似文献   

2.
High‐oleic soybean oil is chemically functionalized in order to mimic the structure and physical properties of hydrogenated castor oil (HCO). The resulting wax‐like material is evaluated for use as an alternative to other commercial wax coatings for the postharvest treatment of fresh citrus fruit. The racemic nature of the material inhibits ordered crystalline arrangement and negatively affects its relative crystallinity (17.7%), hardness (0.59 ± 0.04 mm?1), and melting profile (44–46 °C), with respect to HCO oil (37.7%, 5.33 ± 0.01 mm?1, 83–87 °C). Nevertheless, compounding the new material with carnauba wax (CAR) imparts a very attractive gloss and prevents moisture loss significantly better than polyethylene, shellac, and CAR‐based coatings. Compounding the hydroxy‐functionalized high‐oleic soybean wax may potentially reduce dependence on imported CAR and other ingredients used in citrus coating emulsion formulations. Practical Applications: The soybean oil‐derived material described in this contribution provides two key performance characteristics desired by citrus growers and packing houses: an efficient barrier to moisture loss and an attractive shine. The synthesis of the hydroxy‐wax is facile and mild, and the materials can be readily formulated into emulsions as required for fruit coating applications. Use of the formulated coating can be extended to other agricultural commodities such as avocados, melons, and stone fruit.  相似文献   

3.
Oilseed plants produce huge amounts of fatty acids (FA) stored as triacylglycerols (TAG) in seeds that give a great variation in their composition. The variety and content of TAG directly affect the nutrition and function of lipids. TAG composition of 12 high‐oleic and normal peanut oil samples were profiled by two‐dimensional liquid chromatography (2D LC) coupled with atmospheric pressure chemical ionization mass spectrometry (APCI‐MS). The statistical evaluation of the TAG profiles determined was conducted on the basis of multidimensional data matrix using Principal Component Analysis (PCA). The technique enabled the differentiation of high‐oleic oils from normal peanut oils—as results illustrated TAG of high‐oleic peanut oil were clearly different from those of normal peanut oils. High‐oleic and normal peanut oils had different profiles mainly in the contents of OOO, OPO and POL. This finding provided theoretical foundation for detecting the adulteration of edible oils and analyzing the nutrition and function of high‐oleic peanut oils.  相似文献   

4.
Oil value is determined by the functional qualities imparted from the fatty acid profile. Soybean oil historically had excellent use in foods and industry; the need to increase the stability of the oil without negative health consequences has led to a decline in soybean oil use. One solution to make the oil stable is to have high oleic acid (>70%) and lower linolenic acid content in the oil. Other fatty acid profile changes are intended to target market needs: low‐saturated fatty acid and high stearic acid content in the oil. The objective of this study is to determine the interaction of the high oleic acid oil trait with other alleles controlling fatty acid profiles. Soybean lines containing high oleic acid allele combinations plus other fatty acid modifying alleles were produced, and the seed was produced in multiple field environments over 2 years. Stable high oleic acid with low linolenic acid (<3.0%) was achieved with a 4‐allele combination. The target of >20% stearic acid in the seed oil was not achieved. Reducing total saturated fatty acids below 7% in a high oleic acid background was possible with mutant alleles of both an acyl‐ACP thioesterase B and a β‐ketoacyl‐[acyl‐carrier‐protein] synthase III gene. The results identified allele combinations that met the target fatty acid profile thresholds and were most stable across environments.  相似文献   

5.
Chickens can hepatically synthesize eicosapentaenoic acid (20:5 n‐3) and docosahexaenoic acid (22:6 n‐3) from α‐linolenic acid (ALA; 18:3 n‐3); however, the process is inefficient and competitively inhibited by dietary linoleic acid (LNA; 18:2 n‐6). In the present study, the influence of dietary high‐oleic acid (OLA; 18:1 n‐9) soybean oil (HOSO) on egg and tissue deposition of ALA and n‐3 polyunsaturated fatty acids (PUFA) synthesized from dietary ALA was investigated in laying hens fed a reduced‐LNA base diet supplemented with high‐ALA flaxseed oil (FLAX). We hypothesized that reducing the dietary level of LNA would promote greater hepatic conversion of ALA to very long‐chain (VLC; >20C) n‐3 PUFA, while supplemental dietary HOSO would simultaneously further enrich eggs with OLA without influencing egg n‐3 PUFA contents. Nine 51‐week‐old hens each were fed 0, 10, 20, or 40 g HOSO/kg diet for 12 weeks. Within each group, supplemental dietary FLAX was increased every 3 weeks from 0 to 10 to 20 to 40 g/kg diet. Compared to controls, dietary FLAX maximally enriched the total n‐3 and VLC n‐3 PUFA contents in egg yolk by 9.4‐fold and 2.2‐fold, respectively, while feeding hens 40 g HOSO/kg diet maximally attenuated the yolk deposition of ALA, VLC n‐3 PUFA, and total n‐3 PUFA by 37, 15, and 32%, respectively. These results suggest that dietary OLA is not neutral with regard to the overall process by which dietary ALA is absorbed, metabolized, and deposited into egg yolk, either intact or in the form of longer‐chain/more unsaturated n‐3 PUFA derivatives.  相似文献   

6.
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.  相似文献   

7.
The changes in the content and composition of total fatty acids, phospholipids and sterol esters, and their fatty acids, and of free sterols and tocopherols in developing seeds of a selection of high oleic acid sunflower varieties grown in Bulgaria were examined over a period of 15th to 90th day after flowering by means of various chromatographic methods. Under the climatic and geographical conditions typical for the South-East Balkans phospholipid, sterol-, sterol ester- and tocopherol- species are formed practically completely in the first 15 days after flowering. Until the 90th day, only quantitative changes were detected to give a product with 65% oil content, 1% phospholipids, 0.3% total sterols and 0.09% tocopherols. Oleic acid is the main component in all acyl derivatives, reaching 85% of the total fatty acids while palmitic and stearic acid content is about 4% each. The product is a good quality HOSO with beneficial content of FA and good prospects as a salad and cooking oil.  相似文献   

8.
以顺酐化豆油及油酸封端对腻子专用UPR进行改性,采用三步加料逐步升温催化熔聚法,研究了从多元醇、酸体系及其醇过量、顺酐化豆油的用量、油酸封端比例对UPR性能的影响。试验发现利用顺酐化豆油的用量为11.53%,采用5%的油酸进行封端时,醇过量为12.24%~15.15%,合成的UPR性能较好,其中14.94%为最佳的醇过量值,得到的新型金属腻子专用树脂性能优良。并探索调整一套适用于新型腻子树脂的填料体系,制得一种环保型的金属腻子。  相似文献   

9.
Soybeans are cultivated in the United States chiefly for cooking oil, while the residue after oil extraction (soybean meal) is mostly used in animal feed formulations. High protein content in the defatted soybean meals led to the extraction of pure protein and its application in food products. We selected 44 soybean lines to determine their moisture and protein contents, and their amino acid composition was investigated. Soybean lines with high protein content, one high yielding (R95‐1705), and two high oleic acid (N98‐4445A, S03‐543CR), were selected for protein isolate preparation, hydrolysis using alcalase and gastro‐intestinal (GI) resistance. Furthermore, the GI resistant hydrolysates were fractionated and tested for angiotensin‐I‐converting enzyme (ACE‐I) inhibition activity. The amino acid analysis showed high methionine in the high protein and fatty acid lines (R05‐4494 and R05‐5491), and high cysteine content in one of the high oleic acid soybean line CRR05‐188 in comparison to the check lines (UA‐4805 and 5601‐T). The protein isolate with the highest purity (90–93 %) was derived from the selected lines N98‐4445A and S03‐543CR, and hydrolyzed using alcalase enzyme. The protein hydrolysates (500 µg/mL) showed inhibition of the ACE‐I by 49 %. The results from this study will promote the use of high oleic acid soybeans as a source of protein and peptides with functional activities.  相似文献   

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颜杰  高瀚云 《塑料助剂》2007,(6):52-53,57
为改进豆油下脚料生产的润滑剂油酸酰胺碘值高、放置一段时间后迅速变黄等稳定性差的缺点.采用骨架镍催化剂选择性加氢油酸酰胺。使其中的亚油酸酰胺、亚麻酸酰胺等不饱和组分大部分转化力油酸酰胺而被除去,提高油酸酰胺的含量和使用性能。最佳反应条件为:反应温度160℃。反应压力0.4MPa,反应时间3.0h,催化剂用量3%。采用碘值结合放置后目测的方法进行了产品分析和评估。  相似文献   

13.
Pressure–volume relations and optical Raman and Infrared spectra of polycrystalline 1MNT have been obtained under quasi‐hydrostatic conditions up to 16 and 40 GPa, respectively, by using diamond anvil cell, synchrotron‐based angle‐resolved X‐ray diffraction, and microspectroscopy. The X‐ray measurements show that the pressure–volume relations remain smooth up to 16 GPa at room temperature, while vibrational measurements show no evidence of a phase transition to near 40 GPa. Anomalous increases of several vibrational intensities and bandwidths suggest that subtle molecular distortions and structural modifications occur in the crystal as pressure increases. Decompression experiments indicate the structural modifications are reversible.  相似文献   

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15.
In an effort to develop alternatives for harmful trans fats produced by partial hydrogenation of vegetable oils, oleogels of high‐stearic soybean (A6 and MM106) oils were prepared with sunflower wax (SW) as the oleogelator. Oleogels of high‐stearic oils did not have greater firmness when compared to regular soybean oil (SBO) at room temperature. However, the firmness of high‐stearic oil oleogels at 4 °C sharply increased due to the high content of stearic acid. High‐stearic acid SBO had more polar compounds than the regular SBO. Polar compounds in oil inversely affected the firmness of oleogels. Differential scanning calorimetry showed that wax crystals facilitated nucleation of solid fats of high‐stearic oils during cooling. Polar compounds did not affect the melting and crystallization behavior of wax. Solid fat content (SFC) showed that polar compounds in oil and wax interfered with crystallization of solid fats. Linear viscoelastic properties of 7% SW oleogels of three oils reflected well the SFC values while they did not correlate well with the firmness of oleogels. Phase‐contrast microscopy showed that the wax crystal morphology was slightly influenced by solid fats in the high‐steric SBO, A6.  相似文献   

16.
A range of bio‐based rubbery thermosets have been synthesized by the cationic copolymerization of conjugated soybean oil, styrene, and 1,5‐hexadiene or isoprene as flexible crosslinkers. The thermal, and mechanical properties, as well as the wear behavior, of these new bio‐rubbers are reported. The amount of styrene and the type of diene incorporated have the greatest influence on the properties of the final materials. The largest variations are found in glass transition temperature, storage modulus, tan δ values, crosslink density, and abrasive wear depth, while thermal degradation and extraction analyses showed minimal variations with changes in composition.

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17.
不同饱和度环氧大豆油的合成与性质表征   总被引:1,自引:0,他引:1  
戴宏海  杨丽庭  林博  石光 《广东化工》2007,34(10):31-34
本文用无溶剂法制备环氧大豆油(ESO),研究了反应温度和反应时间对产物环氧值的影响。通过研究环氧大豆油的环氧值与反应时间以及反应温度的关系,选择最佳反应条件。在75℃下,大豆油和过氧乙酸分别反应1、2、3和4 h,分别获得环氧值为0.243、0.317、0.356和0.383 mol/100 g的环氧值不等的环氧大豆油,并研究不同饱和度对环氧大豆油的理化性质的影响。  相似文献   

18.
The role of glycolipids in vegetable oil refining and production of bio‐based fuels has not been disclosed so far. Such investigations required a reliable and reproducible quantitative determination of these compounds. Fundamental data were therefore established on the quantitative determination of glycolipids in vegetable oil gums by means of high‐performance thin‐layer chromatography (HPTLC). Concentrating on five abundant natural glycolipid classes found in these oils, identification of a suitable separation method for the employed glycolipid mixture and those parameters relevant for successful detection were considered in detail. The special importance of sample volume when employing quantitative HPTLC was discussed. Acetone/chloroform/water 6:3:0.4 (v/v/v) was identified as a convenient mobile phase for the investigated issue. A derivatization reagent comprising methanol, copper(II)sulfate pentahydrate, sulfuric acid 98 %, and phosphoric acid 85 % was identified. Subsequent heating at 135 °C for 10 min finished the derivatization and enabled detection at λ = 370 nm. Calibration curves ranging from 1500 to 31.25 ng/mL, regarding both peak area and peak height, were determined. The good correlation of parameters enabled the application of the method to real oil gum samples from sunflower and soybean oil. This revealed that digalactosyldiglycerides in combination with either sterylglucosides or acylated sterylglucosides represented the major glycolipid classes in these oils.  相似文献   

19.
以环氧大豆油(ESBO)、油酸(OA)为主要原料,在无溶剂无催化剂的条件下合成了环氧大豆油-油酸多元醇(P-OA-ESBO),通过红外(FT-IR)和核磁(1H-NMR)对环氧大豆油-油酸多元醇(P-OA-ESBO)的结构进行了表征。然后以P-OA-ESBO、异氟尔酮二异氰酸酯(IPDI)、甘油为主要原料在无催化剂条件下合成了环保型包装用聚氨酯胶黏剂。利用热重分析(TGA)、差示扫描量热法(DSC)、拉伸力学性能测试、PE/OPP复合膜的剥离强度测试及剪切强度测试考察了不同R(NCO/OH)比聚氨酯胶黏剂涂膜的耐热、机械和粘接性能。结果表明:大豆油-油酸多元醇成功改性聚氨酯胶黏剂,相比于传统的大豆油基多元醇改性聚氨酯,该方法更为绿色经济环保,且当R值为1.3-1.5时合成的聚氨酯胶黏剂的力学拉伸和剪切能较好,R值在1.7时合成的聚氨酯胶黏剂剥离强度较优异,可满足PE/OPP膜的基本复合要求。  相似文献   

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