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1.
采用浸提法提取紫色马铃薯中的花色苷,考察了不同溶剂、乙醇体积分数、浸提温度、浸提时间、pH和液料比等因素对浸提效果的影响,确定了最佳单因素水平.通过正交试验,确定了紫色马铃薯中花色苷提取的最佳工艺条件为:乙醇体积分数70%,提取温度50℃,提取时间90 min,pH 1.00,液料比10:1(mL/g).在此条件下,紫色马铃薯中花色苷的一次提取得率为3.4%.液料比和乙醇体积分数是影响紫色马铃薯中花色苷提取率的主要因素,其中,液料比影响最大,达到极显著水平,其次是乙醇体积分数,也达显著水平,时间和温度有一定影响,均不显著.  相似文献   

2.
采用单因素试验与正交试验方法,对乙醇提取岗稔黄酮苷的工艺进行了探讨,研究了岗稔皮与乙醇的质量配比(料液比)、提取时间、提取温度以及乙醇体积分数等因素对岗稔黄酮苷提取得率的影响,结果表明最佳提取工艺条件为料液比1:40、提取时间2.5h、提取温度80℃、乙醇体积分数60%。  相似文献   

3.
优化侧柏叶生发酒的提取工艺。采用正交试验设计,以总黄酮含量、槲皮苷含量的综合评分为指标,考察乙醇体积分数、料液比和提取时间对提取效果的影响。结果表明,优选的提取工艺为乙醇体积分数60%,料液比为1∶12,提取时间12 d。该优选的提取工艺合理可行,侧柏叶生发酒各项指标符合药典规定,工艺重复性好。  相似文献   

4.
以山楂为原料,利用乙醇为浸提剂,研究了熊果酸的提取工艺,分别考察了乙醇浓度、浸提温度、料液比和浸提时间各单因素水平对熊果酸提取效果的影响,并通过正交试验确定了提取熊果酸最佳的工艺条件。结果表明影响熊果酸提取的因素主次顺序为:乙醇浓度浸提温度浸提时间料液比。最佳提取工艺参数为:用体积分数90%的乙醇浸提,料液比1∶30(g/m L),浸提温度80℃,浸提时间2 h。  相似文献   

5.
以玫瑰果实为原料,采用乙醇浸提法提取玫瑰果多酚类物质。通过单因素及正交试验研究了不同的乙醇体积分数、固液比、提取温度、提取时间和提取次数对多酚得率的影响。结果表明:各因素对玫瑰果多酚得率影响的主次顺序为乙醇体积分数>提取温度>料液比>提取时间;优化提取工艺条件为乙醇体积分数75%,固液比1∶20(g∶mL),浸提温度70℃,提取时间40 min,提取2次。在该优化条件下提取,玫瑰果多酚得率达到9.18%。  相似文献   

6.
以夏季茶树老叶为原料,利用乙醇水溶液提取茶皂素,考察液料比、乙醇体积分数、浸提温度和浸提时间对粗提物中茶皂素含量及茶叶中茶皂素得率的影响。单因素试验结果表明,液料比10︰1(mL/g)、乙醇体积分数70%、浸提温度60℃和浸提时间1.5 h时为宜。通过正交试验确定了茶皂素提取的最佳工艺:液料比20︰1(mL/g)、乙醇体积分数60%、浸提温度70℃、浸提时间2 h。试验结果为夏秋茶资源中茶皂素的提取提供参考。  相似文献   

7.
Hartley方法优化菠萝皮渣多酚化合物提取工艺   总被引:2,自引:0,他引:2  
在单因素试验基础上,采用SAS9.2中的响应曲面分析-Hartley方法对菠萝皮渣中的多酚类化合物提取工艺进行优化,建立提取温度、提取时间、乙醇体积分数和液料比4个因素与总多酚得率(Y)之间的编码水平回归模型,并得出各因素对菠萝皮渣总多酚得率的影响顺序为提取温度>提取时间>液料比>乙醇体积分数。在提取温度48.4℃、提取时间73.6min、乙醇体积分数41.6%、液料比46.8:1(mL/g)的条件下,菠萝皮渣总多酚得率最高,可达7.77mg/g,与理论值7.80mg/g基本吻合。响应面法所得的优化提取条件工艺参数可靠,可用于菠萝皮渣中多酚产品的开发。  相似文献   

8.
以黑米为原料,利用乙醇为浸提剂,研究了黑米色素的提取工艺,分别考察了料液比、浸提p H、浸提温度和浸提时间各单因素水平对提取效果的影响,并通过正交试验确定了醇溶法提取黑米色素最佳的工艺条件。结果表明,影响黑米色素提取的因素主次顺序为:浸提时间料液比浸提温度浸提p H。最佳提取工艺参数为:用体积分数95%的乙醇浸提,料液比1∶45(g∶m L),浸提p H3.0,浸提温度80℃,浸提时间90 min。  相似文献   

9.
柿果多酚提取工艺优化   总被引:1,自引:0,他引:1  
采用单因素试验设计,研究乙醇体积分数、料液比、提取时间和提取温度4个因素对柿果总酚及缩合多酚超声提取效果的影响,并采用正交试验设计对提取工艺进行优化。结果表明影响因素对提取效率影响顺序为:乙醇体积分数>料液比>提取时间>提取温度。最佳提取条件为:乙醇体积分数90%、料液比1:40(g/mL)、时间30min、提取温度40℃,在此条件下进行验证实验,总酚提取率为2.061%。  相似文献   

10.
为了确定乙醇浸提法提取粉色马铃薯中花色苷的最佳提取工艺条件,采用单因素和正交试验,考察温度、浸提时间、不同液料比、乙醇体积分数、p H值对花色苷提取效果的影响;同时测定了粉色马铃薯花色苷清除DPPH·能力。结果表明,粉色马铃薯花色苷在可见光范围内的最大吸收波长为520 nm;在温度60℃、浸提时间120 min、液料比10:1、乙醇体积分数50%、p H值1.0的条件下,提取花色苷效果最佳;粉色马铃薯花色苷清除DPPH·能力较强,当粉色马铃薯花色苷浓度达到50 mg/m L时,清除DPPH·能力达到98.45%。  相似文献   

11.
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   

12.
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   

13.
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   

14.
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   

15.
A 9% whey protein (WP) isolate solution at pH 7.0 was heat-denatured at 80°C for 30 min. Size-exclusion HPLC showed that native WP formed soluble aggregates after heat-treatment. Additions of CaCl2 (10–40 mM), NaCl (50–400 mM) or glucono-delta-lactone (GDL, 0.4–2.0%, w/v) or hydrolysis by a protease from Bacillus licheniformis caused gelation of the denatured solution at 45°C. Textural parameters, hardness, adhesiveness, and cohesiveness of the gels so formed changed markedly with concentration of added salts or pH by added GDL. Maximum gel hardness occurred at 200 mM NaCl or pH 4.7. Increasing CaCl2 concentration continuously increased gel hardness. Generally, GDL-induced gels were harder than salt-induced gels, and much harder than the protease-induced gel.  相似文献   

16.
Capillary electrophoresis (CE) and polarized light microscopy (PLM) were utilized in the detection of the adulteration of locust bean gum with guar gum. For CE analyses, standards of locust bean and guar gums were extracted with 30% CH3CN, removing the residual proteins from the gum matrix. A 8.75 mM NaH2PO4-20.6 mM Na2B4O7 buffer, pH 9, was used to separate these proteins and to identify marker proteins that were present in the guar gum. These markers did not co-migrate with components in the extracts of mechanically processed locust bean gum, and are used as indicators of adulteration. Using PLM with toluidine blue and iodine staining techniques, unadulterated locust bean gum samples were distinguished from mixed samples through the differential staining of components in locust bean versus guar and tara gums. These experiments in the use of CE and PLM provide orthogonal and complementary methods for the verification of 'true' positives and the elimination of 'false' positives.  相似文献   

17.
18.
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   

19.
An investigation is described in which various polyfunctional compounds were applied to wool in attempts to stabilize the temporary improvements in wrinkle-recovery brought about by ‘annealing’. Several reactive systems involving formaldehyde were found to produce the desired permanently improved wrinkle-recovery.  相似文献   

20.
《造纸信息》2014,(8):79-79
Ministr y of Industr y and Information Technology confirmed that the main expected targets for energysaving and comprehensive utilization in 2014 are:energy consumption and CO2 emissions per unit of industrial added-value decreases by 4.5%,water consumption per ten thousand Yuan of industrial added-value decreases by7%,comprehensive utilization of industrial solid waste is further improved,and pollution emissions in key industries is markedly reduced.  相似文献   

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