大蓟籽总黄酮及总多酚含量的测定及提取工艺研究

以芦丁和没食子酸分别作为测定总黄酮和总多酚含量的对照品,对大蓟籽中总黄酮及总多酚的含量进行了测定,测得大蓟籽中总黄酮含量5.02%,总多酚含量4.63%。采用超声波辅助提取,通过正交试验,确定了大蓟籽中总黄酮和总多酚的最佳提取条件:乙醇体积分数80%,超声波时间30 min,提取次数3次,料液比1︰15 g/m L,其总黄酮含量达到4.07%(提取率81%),总多酚含量达到3.64%(提取率78.6%)。此提取方法简单易行,提取效率高、稳定性好,适用于工业化生产。     

响应面法优化青海产树莓中总多酚的超声提取工艺研究

对超声辅助提取青海产树莓中总多酚的工艺进行了研究。在单因素试验的基础上选择提取次数、超声时间、乙醇体积分数、料液比4个因素为自变量,以树莓中总多酚的提取率为响应值,进行Box-Behnken中心组合试验设计,采用响应面法(RSM)优化了树莓总多酚的提取工艺。结果表明,超声辅助提取树莓中总多酚的最佳工艺条件为:超声提取2次,乙醇体积分数51%,料液比1︰22(g/m L),超声时间30 min,在此条件下预测总多酚的得率为1.023%。     

超声萃取乌饭树叶多酚及在卷烟中的应用

以一定比例的丙酮溶液为提取溶剂,以乌饭树叶多酚的得率为指标,对超声波萃取乌饭树叶多酚的工艺进行考察,并对所得乌饭树叶多酚进行了卷烟加香试验。以丙酮溶液体积分数、超声功率、固液比、超声温度和超声时间为考察因素,采用单因素和响应面分析试验法同时对乌饭树叶多酚提取工艺进行优化。试验结果确定了采用体积分数为40%的丙酮溶液提取效果最佳,从而得到了40%丙酮提取-超声波萃取的最佳工艺参数为:超声功率116 W、40%丙酮固液比1︰63(g/m L)、超声温度75℃和超声时间15 min。超声波萃取乌饭树叶多酚的最佳得率为2.11%。乌饭树叶多酚卷烟加香应用结果表明,乌饭树叶多酚能掩盖杂气,改善余味,降低刺激感。     

酸浆果实中多酚的提取及其抗氧化能力研究

以酸浆果实为研究对象,对其多酚提取工艺进行优化并分析其(Ferric reducing antioxidant power,FRAP)还原亚铁离子的能力)。采用响应面法对乙醇体积分数、料液比、温度、提取时间进行优化,确定酸浆果实多酚的最佳提取条件,并采用FRAP对多酚提取物的体外抗氧化能力进行分析。结果表明:酸浆果实多酚的最佳提取条件为乙醇体积分数61.5%、料液比1∶15(g/m L)、浸提温度59℃、提取时间102 min,所得多酚得率为0.899%DW,与预测值偏差不大。酸浆多酚10 mg/m L时FRAP值为0.495 mmol/L。研究表明酸浆果实中含有多酚类物质,且具有一定的还原亚铁离子的能力。     

微波辅助提取安梨皮渣中多酚类物质工艺优化

试验以安梨皮渣为原料,研究了微波辅助和常规溶剂法浸提安梨皮渣中的多酚物质的工艺条件。通过单因素试验和正交试验,研究了微波功率、微波处理时间、溶剂浓度、料液比及浸提时间等因素对多酚浸提量的影响,结果表明,按料液比1︰30(g/m L)加入50%乙醇,微波功率540 W处理50 s,再于60℃水浴浸提20 min,安梨皮渣中多酚类物质的提取量可达9.322%,比直接采用50%乙醇60℃提取40 min所得多酚类物质量5.227 mg/g高出78.43%;对两种方法提取的多酚类物质紫外扫描结果显示,微波处理对多酚类物质的分子结构无破坏作用。     

鸡油菌中多酚含量测定的研究

利用溶剂浸提法对鸡油菌中的多酚物质进行提取,采用福林法测定鸡油菌中多酚含量。结果表明,当福林试剂与10%Na2CO3体积比为1︰2,福林试剂体积为4 m L,反应温度为25℃,反应时间为120 min时,鸡油菌多酚的含量为14.04 mg/g,回收率为99.87%,RSD为0.494%,有较好的精密度和准确度。     

挤压改性小扁豆全粉营养蛋糕的研制

小扁豆富含优质植物蛋白质、膳食纤维、多酚等营养物质。以挤压物理改性小扁豆全粉代替部分小麦粉为原料开发营养蛋糕。采用正交试验研究了改性小扁豆粉、泡打粉、白砂糖和鸡蛋添加量对蛋糕焙烤品质的影响。通过感官评定和质构分析,确定了改性小扁豆全粉营养蛋糕制作的最佳配方为粉料100%(挤压小扁豆粉40%、低筋粉60%)、鸡蛋200%、糖60%、牛奶25%、黄油15%、泡打粉3.5%、盐1.5%。     

荞麦米多酚物质的提取及其抗氧化特性

为了获得乙醇提取荞麦米多酚物质的最佳工艺参数,以提取温度、时间、乙醇浓度及料液比为实验因子,以多酚物质得率为响应值,采用响应面设计进行实验。并对优化后荞麦米提取物粉末的抗氧化特性进行了分析。结果表明,影响荞麦米多酚物质得率因素强弱顺序依次为:料液比乙醇浓度提取温度提取时间,荞麦米多酚物质提取最优条件为提取温度56℃、提取时间6.0h、料液比1∶12g/m L、乙醇浓度65%。2mg/m L荞麦提取物对羟自由基在反应时间为20min时具最强清除活性,其清除率为26.88%;对DPPH·的清除在反应时间为30min时,清除率最高,为43.65%;在反应时间为10min时,3mg/m L荞麦提取物表现出最大的还原力,其值为2065.39。     

山竹多酚匀浆的提取条件优化及抗氧化活性

以山竹果皮为原料,采用匀浆提取的方法提取山竹皮中的植物多酚物质,并对其抗氧化活性进行研究。为了确立最佳的提取条件,以提高山竹多酚的得率,采用单因素和正交实验对提取条件进行优化探讨,最终确定了最佳工艺参数:乙醇体积分数为80%、料液比1:8、匀浆时间6 min。山竹果皮中植物多酚物质清除DPPH·自由基IC_(50)值为0.1569 mg/m L,山竹果皮多酚浓度与清除DPPH·自由基效用呈线性关系,且山竹多酚具有一定的抗氧化能力。为山竹多酚提取及抗氧化活性研究提供一定的理论依据,使山竹果皮中的植物多酚物质得到更好的开发利用。     

基于响应面分析方法的超声萃取黑胡椒子多酚工艺条件的优化

研究了以一定比例的乙醇溶液为提取溶剂,以黑胡椒子多酚的得率为指标,对超声波萃取黑胡椒子多酚的工艺进行考察。以乙醇溶液体积百分数、超声温度、料液比、超声时间和超声功率为考察因素,采用单因素和响应面分析试验法同时对黑胡椒子多酚提取工艺进行优化。试验结果确定了采用体积百分数为60%的乙醇溶液提取效果最佳,从而得到了60%乙醇提取-超声波萃取的最佳工艺参数为:超声温度60.60℃、料液比1︰28.18(g/m L)、超声时间13.82 min、超声功率193.81 W,在此条件下得到最高的理论提取率为12.70 mg/g,实际提取率为12.68 mg/g;试验方案及试验结果可显著提高黑胡椒子多酚的得率,显示了超声辅助萃取方法的优越性。     

Reliable identification of grapevine rootstock varieties using RAPD PCR on woody samples

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.     

An internet compendium of analytical methods and spectroscopic information for monomers and additives used in food packaging plastics

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.     

Aroma characterization of various apricot varieties using headspace–solid phase microextraction combined with gas chromatography–mass spectrometry and gas chromatography–olfactometry

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.     

Tests of potential functional barriers for laminated multilayer food packages. Part I: Low molecular weight permeants

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.     

Analysis of benzo[a]pyrene in spiked fatty foods by second derivative synchronous spectrofluorimetry after microwave-assisted treatment of samples

A simple, rapid and inexpensive method has been developed for the determination of benzo[a     

The development of reference materials for paralytic shellfish poisoning toxins in lyophilized mussel. II: Certification study

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.     

Announcing a new international peer-reviewed journal:Food Science and Human Wellness now accepting manuscript submission in English

<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     

Chinese CTP Market

According to Printing and Printing Equipment Industries Association of China（PEIAC）＇s statistics to the plate manufucturer in China, in 2013, the actual offset plate production has reached 346 million square meters in China. Among them, the CTP production volume was 245 million square meters, up by 11% than that of last year; the total sales of the CTP plate was 239 million square meters, up by 13%.     

Preparatory Work of Print China 2015 is Going Smoothly

正Held at Guangdong Modern International Exhibition Center,Print China 2015 will cover 7exhibition halls,besides the original Hall No.3,4,5,6,7,the newly built F zone of Hall 3 will be used too.The total area will be140,000 square meters.Hall 3:Offset and large printing equipment,package printing equipment,post press