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以柴达木新鲜枸杞压榨取汁后得到的枸杞果渣为原料,应用超声波协同酶法提取、大孔吸附树脂纯化和正交试验设计,以枸杞黄酮得率和枸杞多糖得率为指标,得出枸杞果渣中枸杞黄酮和枸杞多糖的最佳制备工艺。结果表明:超声协同酶法提取枸杞黄酮的最佳条件为加酶量4mg/g、乙醇浓度75%、超声温度50℃、超声功率250 W、超声时间55 min;超声波提取枸杞多糖的最佳条件为超声温度60℃、超声时间40 min、料液比1:18、超声波功率200 W;在枸杞黄酮纯化试验中,选择大孔树脂HP-20为最佳,其中最佳吸附条件为上样量25 m L、上样p H值4.0、上样流速2.0 m L/min,最佳解吸条件为洗脱液浓度89%、洗脱液流速2.0 m L/min;纯化后总黄酮含量为64.24%、得率为0.605%,枸杞多糖含量为31.60%、得率为5.08%。 相似文献
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《轻工科技》2021,(9)
以铁皮石斛与罗汉果为原料,研究铁皮石斛罗汉果复合饮料的工艺及配方。采用单因素试验,考察不同的加水比例、提取时间、提取温度,对铁皮石斛和罗汉果汁液品质的影响。采用正交试验方法,优化铁皮石斛罗汉果提取液的制备工艺,确定铁皮石斛罗汉果复合饮料的配方。单因素试验结果,铁皮石斛加水140倍,在90℃温度下提取40min得出的铁皮石斛汁色香味俱佳;罗汉果加水130倍,在90℃温度下提取时间30min得出的罗汉果汁色香味俱佳。铁皮石斛罗汉果复合饮料的最佳工艺配方:铁皮石斛汁与罗汉果汁的比例为1∶1、白糖1.5%、柠檬酸0.04%所制得的铁皮石斛罗汉果复合饮料酸甜可口,色泽、香气俱佳。 相似文献
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讨论了荷叶天然染料提取的工艺及荷叶提取液对真丝绸的染色工艺,测定了真丝绸的染色效果,优化了荷叶天然染料提取及提取液对真丝绸染色的工艺。结果表明:碱性条件下可以提取到更多的荷叶天然染料,其优化的工艺为:碳酸钠0.150 mol/L、提取温度100℃、提取时间60 min、料液比1∶40;提取液对真丝织物直接染色的优化工艺为:染液pH 3左右、染色温度90℃、染色时间60 min、浴比1∶50。荷叶提取液直接染色真丝绸具有较好的耐摩擦色牢度和一定的耐皂洗色牢度,而媒染可以适当提高染色真丝绸的染色牢度。 相似文献
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超声辅助萃取荷叶总黄酮工艺的研究 总被引:2,自引:0,他引:2
为获取荷叶总黄酮的最佳提取工艺,采用超声波提取法对荷叶总黄酮进行提取,以芦丁标准品,在波长510nm处测定吸光度,得回归方程C=0.0925A+0.0063(R=0.9996),通过单因素试验确定出荷叶总黄酮超声提取时较佳的提取工艺为:乙醇浓度60%80%、料液比1 ∶ 251 ∶ 35、提取时间2030min、提取温度3040℃.在此基础上,采用二次通用旋转组合设计优化确定出荷叶总黄酮最佳提取工艺为:按1 ∶ 35 的料液比加入70%乙醇溶液,浸泡4h;而后在超声波清洗器中超声提取30min,超声温度40℃,荷叶总黄酮提取率为7.47%.利用超声波技术提取荷叶总黄酮具有提取率较高,节省时间和溶剂、能耗低等优点. 相似文献
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Since grapevine ( Vitis spp .) rootstock material is being traded increasingly as disbudded woody material a lack of distinctive morphological features on such material necessitates an alternative and reliable means of identification. Methods described here were developed for rapid and efficient extraction of DNA from woody samples rich in phenolic compounds and polysaccharides, and for subsequent identification of varieties by RAPD PCR. Using these methods, and with the application of only one selected RAPD primer, we were able to differentiate sixteen rootstock varieties, including the seven varieties most commonly used in Germany. Problems commonly encountered with reproducibility of RAPD patterns were avoided by choosing primers with a dinucleotide sequence and a high G/C content that allowed a rather high annealing temperature of 45°C. Methods described here should also be useful for other horticultural crops, especially those with woody tissues rich in phenolic compounds and polysaccharides. 相似文献
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John Gilbert Catherine Simoneau David Cote Achim Boenke 《Food Additives & Contaminants》2000,17(10):889-893
An internet website (http://cpf.jrc.it/smt/) has been produced as a means of dissemination of methods of analysis and supporting spectroscopic information on monomers and additives used for food contact materials (principally packaging). The site which is aimed primarily at assisting food control laboratories in the European Union contains analytical information on monomers, starting substances and additives used in the manufacture of plastics materials. A searchable index is provided giving PM and CAS numbers for each of 255 substances. For each substance a data sheet gives regulatory information, chemical structures, physico-chemical information and background information on the use of the substance in particular plastics, and the food packaging applications. For monomers and starting substances (155 compounds) the infra-red and mass spectra are provided, and for additives (100 compounds); additionally proton NMR are available for about 50% of the entries. Where analytical methods have been developed for determining these substances as residual amounts in plastics or as trace amounts in food simulants these methods are also on the website. All information is provided in portable document file (PDF) format which means that high quality copies can be readily printed, using freely available Adobe Acrobat Reader software. The website will in future be maintained and up-dated by the European Commission's Joint Research Centre (JRC) as new substances are authorized for use by the European Commission (DG-ENTR formerly DGIII). Where analytical laboratories (food control or other) require reference substances these can be obtained free-ofcharge from a reference collection housed at the JRC and maintained in conjunction with this website compendium. 相似文献
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Sophie Guillot Laurence Peytavi Sylvie Bureau Renaud Boulanger Jean-Paul Lepoutre Jean Crouzet Sabine Schorr-Galindo 《Food chemistry》2006
The characterization of the aromatic profile of several apricot cultivars with molecular tracers in order to obtain objective data concerning the aromatic quality of this fruit was undertaken using headspace–solid phase microextraction (HS–SPME). Six apricot cultivars were selected according to their organoleptic characteristics: Iranien, Orangered, Goldrich, Hargrand, Rouge du Roussillon and A4025. The aromatic intensity of these varieties measured by HS–SPME–Olfactometry were defined and classified according to the presence and the intensity of grassy, fruity and apricot like notes. In the six varieties, 23 common volatile compounds were identified by HS–SPME–GC–MS. Finally, 10 compounds, ethyl acetate, hexyl acetate, limonene, β-cyclocitral, γ-decalactone, 6-methyl-5-hepten-2-one, linalool, β-ionone, menthone and (E)-hexen-2-al were recognized by HS–SPME–GC–O as responsible of the aromatic notes involved in apricot aroma and considered as molecular tracers of apricot aromatic quality which could be utilized to discriminate apricot varieties. 相似文献
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Jesus Simal-Gandara Miguel Sarria-Vidal Arjen Koorevaar Rinus Rijk 《Food Additives & Contaminants》2000,17(8):703-711
The advent of the functional barrier concept in food packaging has brought with it a requirement for fast tests of permeation through potential barrier materials. In such tests it would be convenient for both foodstuffs and materials below the functional barrier (sub-barrier materials) to be represented by standard simulants. By means of inverse gas chromatography, liquid paraffin spiked with appropriate permeants was considered as a potential simulant of sub-barrier materials based on polypropylene (PP) or similar polyolefins. Experiments were performed to characterize the kinetics of the permeation of low molecular weight model permeants (octene, toluene and isopropanol) from liquid paraffin, through a surrogate potential functional barrier (25 μm-thick oriented PP) into the food simulants olive oil and 3% (w/v) acetic acid. These permeation results were interpreted in terms of three permeation kinetic models regarding the solubility of a particular model permeant in the post-barrier medium (i.e. the food simulant). The results obtained justify the development and evaluation of liquid sub-barrier simulants that would allow flexible yet rigorous testing of new laminated multilayer packaging materials. 相似文献
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Yoko Uematsu Keiko Hirata Kumi Suzuki Kenji Iida Kazuo Saito 《Food Additives & Contaminants》2001,18(2):177-185
BADGE.2HCl and BFDGE.2HCl were determined in 28 samples of ready-to-drink canned coffee and 18 samples of canned vegetables (10 corn, 5 tomatoes and 3 others), all from the Japanese market. HPLC was used as the principal analytical method and GCMS for confirmation of relevant LC fractions. BADGE.2HCl was found to be present in one canned coffee and five samples of corn, BFDGE.2HCl in four samples of canned tomatoes and in one canned corn. No sample was found which exceeded the 1mg/kg limit of the EU for the BADGE chlorohydrins. However the highest concentration was found for the sum of BFDGE.2HCl and BFDGE.HCl.H2O at a level of 1.5mg/kg. A Beilstein test confirmed that all cans containing foods contaminated with BADGE.2HCl or BFDGE.2HCl had at lest one part coated with a PVC organosol. 相似文献
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A strong science base is required to underpin the planning and decision-making process involved in determining future European community legislation on materials and articles in contact with food. Significant progress has been made in the past 5 years in European funded work in this area, with many developments contributing to a much better understanding of the migration process, and better and simpler approaches to food control. In this paper this progress is reviewed against previously identified work-areas (identified in 1994) and conclusions are reached about future requirements for R&D to support legislation on food contact materials and articles over the next 5 or so years. 相似文献
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M. S. Garcí a-Falc n J. Simal-G ndara S. T. Carril-Gonz lez-Barros 《Food Additives & Contaminants》2000,17(12):957-964
A simple, rapid and inexpensive method has been developed for the determination of benzo[a 相似文献
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H. J. Van Den Top A. Boenke P. A. Burdaspal J. Bustos H. P. Van Egmond T. Legarda A. Mesego A. Mourino W. E. Paulsch C. Salgado 《Food Additives & Contaminants》2001,18(9):810-824
This paper describes the second part of a project undertaken to develop certified mussel reference materials for paralytic shellfish poisoning toxins. In the first part two interlaboratory studies were undertaken to investigate the performance of the analytical methodology for several PSP toxins, in particular saxitoxin and decarbamoyl-saxitoxin in lyophilized mussels, and to set criteria for the acceptance of results to be applied during the certification exercise. Fifteen laboratories participated in this certification study and were asked to measure saxitoxin and decarbamoyl-saxitoxin in rehydrated lyophilized mussel material and in a saxitoxin-enriched mussel material. The participants were allowed to use a method of their choice but with an extraction procedure to be strictly followed. The study included extra experiments to verify the detection limits for both saxitoxin and decarbamoyl-saxitoxin. Most participants (13 of 15) were able to meet all the criteria set for the certification study. Results for saxitoxin.2HCl yielded a certified mass fraction of <0.07 mg/kg in the rehydrated lyophilized mussels. Results obtained for decarbamoyl-saxitoxin.2HCl yielded a certified mass fraction of 1.59+/-0.20 mg/kg. The results for saxitoxin.2HCl in enriched blank mussel yielded a certified mass fraction of 0.48 +/- 0.06 mg/kg. These certified reference materials for paralytic shellfish poisoning toxins in lyophilized mussel material are the first available for laboratories to test their method for accuracy and performance. 相似文献
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《肉类研究》2014,(2)
<正>We are pleased to announce the launch of a new international peer-reviewed journal-Food Science and Human Wellness,ISSN 2213-4530,which is an open access journal,produced and hosted by Elsevier B.V.on behalf of Beijing Academy of Food Sciences.Food Science and Human Wellness is an international peer-reviewed English journal that provides a forum for the dissemination of the 相似文献