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三种海带多糖粗品提取条件的研究 总被引:4,自引:0,他引:4
采用复合酶解法提取高得率海带多糖,并对三种海带多糖的分离条件进行了深入探讨。结果表明,加入海带粉重2%的复合酶,在pH6.0、50℃酶解6h时总多糖得率最高,可达9.68%。复合酶(纤维素酶、果胶酶和蛋白酶)的最佳配比为2∶1∶1。氯化钙沉淀褐藻胶的最佳条件为:加入1mol/LCaCl2(其中氯化钙与滤液体积比为1.8∶8),60℃加热15min得到褐藻酸钙粗品。CTAB沉淀褐藻糖胶的最佳条件:2%CTAB与滤液体积比为1.2∶5。加入2moL/L氯化钾溶解CTAB-FPS络合物后加入乙醇至60%得到褐藻糖胶粗品。在分离除去褐藻糖胶的滤液中加入乙醇至85%,得到褐藻淀粉粗品。其中褐藻胶、褐藻糖胶、褐藻淀粉粗品的含量分别为9.76%(以褐藻酸钙计)、2.03%和0.84%。 相似文献
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以豆腐渣和海带为原料水解制备水溶性膳食纤维(SDF)和多糖,并制备复合膳食纤维固体饮品.用碱法和酶法结合提取大豆不溶性膳食纤维(IDF)和SDF,采用复合酶法制备海带多糖.结果表明:大豆IDF的提取条件为氢氧化钠浓度5%,浸泡时间60min、浸泡温度80℃;纤维素酶添加量为IDF重量的1%,纤维素与水的比例为1:12(W/V),pH为4.5,水解时间为12h,水解温度为40℃,在以上条件下,SDF的产率为36.01%.提取海带多糖条件为加入海带粉重1%的复合酶,复合酶(纤维素酶、果胶酶和蛋白酶)的最佳配比为2:1:2,在pH6.0、50℃酶解6h总多糖得率最高,可达10.71%. 相似文献
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双酶法提取蓝靛果果渣中花色苷酶解条件的研究 总被引:3,自引:1,他引:2
为研究从蓝靛果果渣中酶法提取花色苷的工艺参数,通过单因素和正交试验确定纤维素酶、果胶酶单独水解和双酶复合水解条件.结果表明:采用纤维素酶水解的最佳条件为:温度30℃,时间120 min,固液比1:8,酶用量10 mg/g,pH 4.5;采用果胶酶水解的最佳条件为:温度50℃,时间120 min,固液比1:6,酶用量8 mg/g,pH4.0.采用双酶复合水解比单独使用纤维素酶花色苷提取率提高3.05倍,比单独使用果胶酶花色苷提取率提高1.53倍;先使用纤维素酶再使用果胶酶,花色苷提取率比先使用果胶酶再使用纤维素酶提高1.06倍. 相似文献
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水酶法提取酸浆籽油工艺的研究 总被引:1,自引:0,他引:1
通过实验研究水酶法提取酸浆籽油的工艺条件.研究结果表明,当酸浆籽与水的质量比为1:5,混合酶(纤维素酶和果胶酶按1:0.6的比例混合)添加量2%,酶解时间6 h,水解温度45℃,pH在4.5~5.0,3200 r/min的离心机离心30 min,溶剂:酸浆籽粕(v/w)=(0.8~1),提取率可达96.0%.提取的油脂更易于精炼,营养成分保存率高,品质好. 相似文献
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酶法提高芋头浆中淀粉水解率的工艺条件研究 总被引:1,自引:0,他引:1
针对芋头浆中被粘多糖蛋白质和果胶等粘性物质包裹的淀粉难以水解的难题,研究采用复合纤维素酶-果胶酶和中性蛋白酶分步酶解法对芋头浆进行前处理,以提高α-淀粉酶酶解芋头浆淀粉的水解率。通过单因素实验和正交实验优化,结果表明,复合纤维素酶-果胶酶酶解最佳条件为:添加量0.2%,酶配比1∶1,pH5.8,酶解时间40min;中性蛋白酶酶解最佳条件为:添加量0.8%,pH7.3,酶解温度48℃,作用时间7.0h,该条件下,芋头浆出汁率和蛋白质水解率分别达到74.67%和40.46%。对经上述酶法预处理后的芋头浆中的淀粉进行酶水解,其水解率高达87.39%,与芋头原浆直接酶解相比提高了33.07%。 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