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1.
Folin-Ciocalteu比色法测定大麦提取液中总多酚的含量   总被引:13,自引:1,他引:13  
刘清  李玉  姚惠源 《食品科技》2007,32(4):175-177
采用Folin-Ciocalteu(FC)比色法测定大麦提取液中总多酚的含量,确定以没食子酸为标准的最佳反应条件。结果表明,FC试剂浓度为0.2mol/L,Na2CO3溶液浓度为15%,在室温下反应60min,浓度在1~9μg/mL时与其吸光值有良好线性关系。方法操作简单、结果重现性好,可用来测定大麦提取物中总多酚的含量。  相似文献   

2.
研究Folin-Ciocalteu 比色法测定沙苑子中多酚含量的优化条件,并以优化的条件测定沙苑子不同溶剂提取物中多酚的含量。结果表明:Folin-Ciocalteu 显色剂(经稀释10 倍)用量1.00mL、7.5g/100mL Na2CO3 用量3.00mL、反应温度25℃、反应时间120min、测定波长647nm 为沙苑子中多酚含量测定的最佳条件,所用没食子酸标准品在10~100μg/mL 范围内与吸光度呈良好的线性关系(y=0.0081x - 0.0249,R2=0.9996);沙苑子甲醇、乙醇和丙酮溶液提取物的质量浓度为1g/100mL 左右时较适合测定其多酚的含量。  相似文献   

3.
以没食子酸为标准品,探究福林-酚(Folin-Ciocalteu)比色法检测核桃青皮果蔬酵素总多酚含量的最优条件,对检测波长、碳酸钠和Folin-Ciocalteu试剂用量、显色温度及显色时间进行了优化,并对该分析方法进行了评价。结果表明,总多酚含量测定的最优条件为检测波长696 nm、样品液1 mL、10% Folin-Ciocalteu试剂2.5 mL、12%碳酸钠溶液1 mL、显色温度45 ℃,显色时间0.5 h。多酚含量在0~6 μg/mL范围内与吸光值呈良好的线性关系(y = 0.072 43x-0.000 91,R2 = 0.999 67),该法平均回收率为102.2%(RSD=2.35%)。该方法准确度高、重复性好,适于核桃青皮果蔬酵素总多酚含量的测定,此条件下测得核桃青皮果蔬酵素总多酚含量为3.26 mg/mL。  相似文献   

4.
采用Folin-Ciocalteu法测定黑莓提取液中总多酚含量,确定以没食子酸为标准的最佳测定条件。结果表明:在5 mL的反应体系中,吸取0.5 mL样品,先加入2.5 mL 0.1 mol/L Folin-Ciocaltou试剂振荡后,再加入2 mL 7.5%Na2CO3溶液,摇匀,25℃显色120 min,在765 nm波长下测定吸光度,没食子酸浓度在5 mg/L~60 mg/L范围内与吸光度存在较好的线性关系。此方法操作简单、稳定性及结果重现性好。利用Folin-Ciocalteu法测定黑莓样品液中没食子酸的平均添加回收率达到100.2%,RSD为1.40%。  相似文献   

5.
赵红  马尚玄  钟涛  徐荣  付镓榕 《食品工业》2022,(12):294-298
以没食子酸为标准品,对Folin-Ciocalteu比色法测定澳洲坚果青皮中多酚含量的条件进行优化。结果表明,最优检测条件为:检测波长762 nm, Folin-Ciocalteu试剂加入量1 mL, 15%的Na2CO3溶液加入量3 mL,加蒸馏水定容至10 mL,显色温度40℃,显色时间60 min,多酚质量浓度在20~80μg/mL范围内与吸光度呈良好的线性关系(R2=0.999 0)。该方法的平均回收率为100.65%,相对标准偏差为1.27%。该方法操作简便,重复性、稳定性好,精密度、回收率高,可用于澳洲坚果青皮多酚含量的测定。  相似文献   

6.
摘要:对Folin-Ciocalteu法测定果酒中总多酚含量进行了研究。经过一系列优化实验,提出Folin-Ciocalteu法的最适测定程序为1.0mL样品提取液中依次加入4.0mL水、2mL显色剂和3mLl5%碳酸钠溶液,摇匀,30℃下显色30min,在760nm波长下测定吸光度。采用此方法对水蜜桃果酒中添加没食子酸,平均回收率为97%-99.5%.  相似文献   

7.
多酚化合物的种类和含量是反映食醋营养功能和品质的重要指标之一。紫外可见分光光度法是目前食品中总多酚含量检测研究中应用最广泛的方法之一。通过试验分析了Folin-Ciocalteu试剂测定食醋总多酚含量方法中样品制备、显色剂用量、显色条件和测量时间等因素对分子吸收光谱的影响,基于此,确定了食醋总多酚含量的测定方法,并对中国四大名醋中总多酚含量进行了分析。以没食子酸为校正标准品,配制1%的食醋样品水溶液,取1 mL于10 mL容量瓶中,于8 min内加入0.5 mL Folin-Ciocalteu试剂和1.5 mL 20%的碳酸钠溶液,暗处显色2 h后,在20 min内于760 nm测量其吸光度值。方法验证结果表明,没食子酸标准溶液在2.0~10.0μg/mL范围内线性关系良好,线性回归方程为Y=0.1148X-0.2087,相关系数R~2=0.9992,平均回收率为97.2%,RSD为1.37%。该方法操作简易、检测成本低、重复性良好、测定精度较高,可以为我国食醋中总多酚含量测定行业标准的建立提供有效的技术参考。  相似文献   

8.
Folin-Ciocalteu 比色法测定苹果渣中的多酚   总被引:6,自引:0,他引:6  
韩菊  魏福祥 《食品科学》2010,31(4):179-182
采用超临界CO2 萃取技术从苹果渣中提取多酚,以没食子酸为标准物质,系统研究了Folin-Ciocalteu(FC)比色法测定多酚的条件,建立了Folin-Ciocalteu 比色法测定苹果渣中多酚的方法。适宜的显色条件为FC 试剂用量0.3mL、饱和碳酸钠溶液用量1.5mL、反应时间20min、反应温度25~35℃。结果表明:在1~10μg/mL 范围内,没食子酸吸光度与其质量浓度呈良好的线性关系,r = 0.9994;并进行了高、中、低3 个不同加标水平的加标回收率测定实验,相应的回收率分别为99.66%、98.79%、98.20%,平均值为98.82%,RSD 为1.93%。该法测定样品快速、准确,重复性好,可应用于实际样品的测定。  相似文献   

9.
改良的Folin-Ciocalteu比色法测定核桃外果皮中总多酚含量   总被引:1,自引:0,他引:1  
目的:建立核桃外果皮中总多酚含量的比色测定方法。方法:以没食子酸为对照品,对测定核桃外果皮中总多酚含量的比色条件,包括检测波长、碳酸钠溶液用量、Folin-Ciocalteu试剂用量、反应温度及时间对吸光值的影响进行了研究。结果:对照品标准曲线在1~7μg/mL范围内为y=0.1031x+0.0793,R2=0.9996,线性关系良好,测定方法为采用核桃外果皮中总多酚提取液1.0mL,Folin-Ciocalteu试剂1.0mL、15%的碳酸钠溶液4.0mL、30℃显色1.5h,平均回收率为100.2%(RSD=0.91%)。此条件下测得核桃外果皮中总多酚含量为3.306mg/g。结论:该方法简便快速、结果准确、重现性和稳定性好,可用于核桃外果皮中总多酚含量的测定。  相似文献   

10.
建立酱香型酒糟中总黄酮及总多酚含量测定方法。以槲皮素为对照品,采用紫外分光光度法测定酱香型酒糟中总黄酮含量;以没食子酸为对照品,用Folin-Ciocateu比色法测定酒糟中总多酚含量,并对其测定条件进行了优化。结果表明,Folin-Ciocalteu比色法最优的测定条件为:加入Folin-Ciocalteu试剂2.5 mL、10% Na2CO3溶液4 mL,在室温下显色80 min。槲皮素和没食子酸质量浓度分别在0.021 0~0.105 0 g/L(R2 = 0.997 6)和0.000 5~0.005 7 g/L(R2 = 0.999 7)范围内与吸光度值线性关系良好,平均回收率分别为99.12%、99.82%,相对标准偏差(RSD)分别为0.61%、0.33%;茅台酱香型酒糟中总黄酮及总多酚含量分别为20.40 mg/g和4.78 mg/g。此方法操作简单,稳定性以及重复性良好,结果准确可靠,适用于酱香型酒糟总黄酮和总多酚含量的测定。  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.
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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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   

20.
<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   

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