共查询到13条相似文献,搜索用时 15 毫秒
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Hiromi Yoshida Yuki Hirakawa Yoshiyuki Mizushina Tomoko Tanaka 《European Journal of Lipid Science and Technology》2002,104(6):347-352
Whole sunflower seeds (Helianthus annuus L.) were exposed to microwaves for 6, 12, 20 or 30 min at a frequency of 2450 MHz. The hulls were then stripped from the seeds. Molecular species and fatty acid distributions of triacylglycerols (TAGs), isolated from total lipids in the hulls, were analyzed by a combination of argentation thin‐layer chromatography (TLC) and gas chromatography. A modified argentation TLC procedure, developed to optimize the separation of the TAGs, provided 10 different groups of TAGs, based on both the degree of unsaturation and the total fatty acid chain‐length. Dilinoleolein (29.5—30.2 wt‐%), trilinolein (18.2—24.2 wt‐%), dilinoleopalmitin and dilinoleostearin (17.0—18.1 wt‐%), palmitoleolinolein and stearoleolinolein (11.4—14.0 wt‐%) and dioleolinolein (7.5—8.6 wt‐%) were the main TAGs detected after microwave roasting. However, roasting caused a significant decrease (p < 0.05), not only in TAG molecular species containing more than four double bonds, but also in the amounts of diene species present in TAGs. These results suggest that microwaves should affect TAGs in the hulls more significantly (p < 0.05) than those in the sunflower kernels. 相似文献
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Antioxidant activity of methanolic extracts of peanut hulls (MEPH) was evaluated in soybean and peanut oils after accelerated
oxidation at 60°C. Results showed that the oils with 0.12, 0.48, and 1.20% MEPH had significantly (P<0.05) lower peroxide values and acid values than the control after storage at 60°C. Moreover, oils with 0.48 and 1.20% MEPH
were significantly (P<0.05) superior to 0.02% butylated hydroxyanisole (BHA) in reducing oxidation of both oils. Negative synergism was observed
when 0.48 and 1.20% MEPH were mixed with 0.01% dl-α-tocopherol or 0.01% BHA in soybean oil compared to MEPH alone. 相似文献
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In this study, the effect of ultrasound-assisted extraction (UAE) on oil yield and content of functional food ingredients of hulled and non-hulled sunflower is discussed and compared with conventional extraction methods. The optimum extraction parameters for UAE were as follows: n-hexane as extracting solvent, average particle size 250 ± 12 µm, extraction time 2 h, solid-to-solvent ratio 1:12, ultrasound frequency 24 kHz and temperature 50°C. Furthermore, the chromatograph showed that sunflower oil extracted by the UAE was rich in α-Linolenic acid (ω-3). In addition, a marginal reduction in peroxide values and tocopherols were determined. 相似文献
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Suna Kim Jaebok Park Kyeong Hwang 《Journal of the American Oil Chemists' Society》2002,79(12):1267-1270
The FA compositions by parts of Korean red pepper (Capsicum annuum L.) were analyzed, and the changes in FA composition and antioxidative activity in pigment extracts due to processing were
investigated. The main FA in the pericarp and seeds were palmitic, oleic, and linoleic acids. Linoleic acid in the seeds was
73.9% of the total FA, or about 1.7 times as much as in the pericarp. Linolenic acid was scarcely present in the seeds. The
percentages of unsaturated FA in the pericarp and seeds were 73.3 and 83.2, respectively. The ratios among FA varied according
to the processing conditions, but the FA compositions themselves remained approximately the same. The antioxidative activity
of pigment extracts in the photooxidation of linoleic acid was measured by monitoring oxygen consumption and conjugated diene
formation. Changes in drying methods resulted in significant differences in antioxidative activity, but changes in storage
conditions had little effect. Conjugated diene formation and oxygen consumption were positively correlated. An improved drying
method could allow the antioxidative activity of red pepper pigments to be conserved. 相似文献
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ABSTRACTPhenolic compounds have been reported to show both antioxidant and pro-oxidant properties. The effects of spray drying conditions on the balance between antioxidant and pro-oxidant properties of orange peel extract have been evaluated in this work. The inlet drying temperatures (ranging between 100 and 175°C) gave no significant effect on the redox recoveries. On the other hand, the main air flow rate (between 28 and 38?m3/h) and feed pump rate (between 4 and 7?mL/min) significantly affected the pro-/antioxidant recovery ratio. The ratios of pro-/antioxidant recovery were found to be between 1.00 and 1.13, and the pro-oxidant and antioxidant recoveries in this study were found to be between 87–96 and 83–93%, respectively. 相似文献
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Multivariate model for the prediction of soluble condensed tannins in crude extracts of polyphenols from canola and rapeseed hulls 总被引:1,自引:0,他引:1
M. Naczk J. Pink R. Amarowicz D. Pink F. Shahidi 《Journal of the American Oil Chemists' Society》2001,78(4):411-414
The feasibility of using ultraviolet spectrophotometry to develop multivariate models for prediction of soluble condensed
tannins (SCT) content in crude polyphenols extracts from canola and rapeseed hulls was investigated. The polyphenols were
extracted from hulls using 70% (vol/vol) aqueous acetone. Partial least squares regression was used to correlate the spectral
data of the crude polyphenols in methanol between 265–295 nm with the SCT content in hulls. Both the proanthocyanidin (P)
and the vanillin (V) assays were used to provide reference data for creating the models. The predictive ability of the models
is good, as indicated by the RPD values [the ratio of the standard deviation of data to the standard error of calibration
(SEC) of above 5. Additionally, the SEC values suggest that P is superior to V in predicting the SCT content of hulls using
this method. 相似文献
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以高分子化合物——聚乙烯醇缩丁醛(PVB)、聚氧乙烯聚氧丙烯嵌段共聚物(F68)、聚乙烯吡咯烷酮(PVP)及其分别与非离子型表面活性剂脂肪醇聚氧乙烯醚(AEO-6)复配作为分散剂,研究不同分散剂对醇溶性白板笔墨水红色颜料分散体系稳定性的影响。通过离心分离-吸光度测试、粒径分析判断其稳定性;通过流变性测试探究高分子化合物与AEO-6之间的作用关系。将稳定性好的分散剂用于制备红色白板笔墨水,并通过流变性测试、粒径分析表征墨水的稳定性能。结果表明,采用3种高分子分散剂的红色颜料分散体系稳定性好,且添加质量分数为1%PVB的体系稳定性最佳。在高分子分散剂与AEO-6复配分散的颜料体系中,高分子分散剂对体系稳定性起主导作用,AEO-6并没有起到明显的作用。在红色白板笔墨水中,PVB分散的墨水体系稳定性最佳,此结果与红色颜料分散体系相一致。 相似文献
9.
Styrene‐maleic acid copolymers were synthesized by free radical polymerization. Encapsulated pigment red 122 dispersions were prepared by sedimentation with these copolymers. Effects of copolymer structure such as molar content of maleic acid, molecular weight, and the amount of copolymers on stability and particle size of dispersion were investigated. The results showed that encapsulated pigment dispersion with higher stability, smaller particle size, and narrower particle distribution could be achieved when the molar content of maleic acid was at 0.43 and the intrinsic viscosity was at 79.65 ml/g with amount of copolymers 10%. The encapsulated layer was about 5 nm which could be observed by TEM. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007 相似文献
10.
Anil Kumar 《Chemical Engineering Communications》2019,206(8):1072-1086
A novel green synergistic reactive extraction technique for the removal of lactic acid (LA) from aqueous solution was explored. Response surface methodology (RSM) was applied to optimize the process variables for LA synergistic reactive extraction using a mixture of trioctylamine and Aliquat336 as extractants. During this present investigation, 2-butanol and sunflower oil were used as organic and green diluent. Systematic investigation has been carried out to obtain the optimum process conditions viz. initial LA concentration, pH of aqueous solution, extractant ratio, extractant concentration, solvent ratio, phase ratio, temperature, stirring speed, and contact time for maximizing the LA distribution coefficient (KD) and extraction efficiency (%, η). The highest experimentally achievable LA distribution coefficient (KD) and extraction efficiency (%) at optimized process conditions were found to be in close agreement with those predicted by numerical optimization using RSM. Thus, the results of present finding have been shown a great ability of sunflower oil as an economic and environmentally friendly green solvent for LA extraction. 相似文献
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Amit Keshav Kailas L. Wasewar Shri Chand 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2009,84(4):484-489
BACKGROUND : Propionic acid is widely used in chemical and allied industries and can be produced by biocultivation in a clean and environmentally friendly route. Recovery of the acid from the dilute stream from the bioreactor is an economic problem. Reactive extraction is a promising method of recovering the acid but suffers from toxicity problems of the solvent employed. There is thus a need for a non‐toxic solvent or a combination of less toxic extractants in a non‐toxic diluent that can recover acid efficiently. RESULTS: The effect of different extractants (tri‐n‐butylphosphate (TBP), tri‐n‐octylamine (TOA) and Aliquat 336) and their mixed binary solutions in sunflower oil diluent was studied to find the best extractant‐sunflower oil combination. Equilibrium complexation constant, KE, values of 4.02, 3.13 and 1.87 m3 kmol?1 were obtained for propionic acid extraction using Aliquat 336, TOA and TBP, respectively, in sunflower oil. The effect of different modifiers (1‐decanol, methylisobutyl ketone, butyl acetate and dodecanol) on the extraction was also studied and it was found that modifiers enhance extraction, with 1‐decanol found to be the best. CONCLUSION: The problem of toxicity in reactive extraction can be reduced by using a non‐toxic diluent (sunflower oil) or a modifier in a non‐toxic solvent, with the extractant. The addition of modifiers was found to improve the extraction. Copyright © 2008 Society of Chemical Industry 相似文献