芦笋老茎中提取芦丁的研究

以芦笋老茎为原料,采用超声波辅助提取和乙醇浸提两种方法,研究提取温度、超声功率、乙醇体积分数和料液比对芦丁提取的影响,通过单因素试验与正交试验优化芦丁提取工艺条件。结果表明:超声波辅助法对芦笋老茎中芦丁得率明显高于乙醇浸提法,超声功率90 W,乙醇体积分数60%,提取温度80℃,料液比1∶25(m∶V)为最佳提取工艺。该条件下芦丁得率为4.53%。     

文冠果壳总皂苷超声波辅助提取工艺优化

采用超声波辅助提取文冠果壳中的总皂苷。在原料粒度、液料比、乙醇体积分数、超声时间、超声功率等单因素试验基础上,利用响应面法优化文冠果壳总皂苷的提取工艺结果表明:液料比和乙醇体积分数、液料比和超声功率、超声时间与功率的交互作用对文冠果壳中总皂苷提取率有显著影响;最佳提取工艺为液料比34.1∶1(V∶m)、乙醇体积分数87.6%、超声时间29.7min、超声功率117.9 W,该条件下总皂苷的提取率为0.804 8%,与模拟预测值高度吻合。     

超声波辅助提取莲子心总黄酮的响应面优化

研究超声波辅助提取莲子心总黄酮的最佳工艺条件。单因素试验考察乙醇体积分数、超声温度、超声功率、料液比、超声时间对总黄酮提取得率的影响,在单因素试验基础上,采用Box-Benhnken响应曲面法考察乙醇体积分数、料液比、超声温度及其交互作用对总黄酮得率的影响。利用软件Design Expert 6.0.1对试验数据进行回归分析,得到二次多项式回归方程预测模型。结果表明,莲子心总黄酮的提取工艺最佳条件为乙醇体积分数80%,料液比1∶16(g/m L),超声温度50℃,超声功率120 W,超声时间20 min,此条件下总黄酮的提取得率为3.071 5%,与预测值基本一致。     

超声波辅助提取栀子花中多酚类物质工艺的优化

目的:探讨多酚类物质超声波辅助提取最佳工艺。方法:采用超声波辅助提取栀子花中的多酚类物质,在选取乙醇体积分数、超声时间、超声功率和料液比4个单因素试验的基础上,再进行正交试验、极差分析、方差分析和多重比较。结论:栀子花中多酚类物质提取率的最佳提取工艺条件为:料液比为1:20,超声波功率为150W,乙醇体积分数为70%,超声时间为30min,此时提取率最大为6.905%。     

响应面优化超声辅助提取昆仑雪菊原花青素的工艺研究

以昆仑雪菊为原料,采用响应面法优化昆仑雪菊中原花青素超声波辅助提取条件.通过单因素试验和Box-Behnken Design试验研究超声功率、料液比、不同乙醇体积分数提取溶剂、盐酸用量4个变量对昆仑雪菊原花青素响应值的影响程度.结果表明,最优工艺参数为超声功率为35W、料液比为1∶20、乙醇体积分数60％vol、盐酸用量为3.5mL.昆仑雪菊原花青素平均提取率为1.76％,与理论预测值相比,其相对误差约为0.03％,且重复性很好,说明提取工艺稳定可靠.     

响应面试验优化超声波辅助提取莲房原花青素工艺

在单因素试验的基础上,采用响应面试验研究乙醇体积分数、液料比、超声波功率和超声时间对莲房原花青素得率的影响,通过建立超声波辅助提取莲房原花青素的多元回归模型,优化莲房原花青素的提取工艺参数。结果表明,乙醇体积分数对莲房原花青素得率的影响最大,其次是液料比和超声波功率,超声时间对得率的影响相对较小。在乙醇体积分数45%、液料比21∶1（mL/g）、超声波功率700 W、超声时间15 min时,莲房原花青素得率最大,为6.81%,与模型理论预测值相近,说明该模型回归性良好,试验的拟合程度高,可以用于莲房原花青素得率的预测,为莲房原花青素作为天然抗氧化剂的应用提供一定的科学数据。     

松籽壳总黄酮超声提取工艺响应面优化

为研究松籽壳总黄酮超声提取工艺,以超声波功率、乙醇体积分数、料液比、提取时间为考察因素,采用Box-Be-hnken试验设计进行工艺参数优化。结果表明,松籽壳总黄酮的最优提取工艺条件:超声波功率250W、乙醇体积分数50%、料液比1∶25(m∶V)、提取时间31min。该条件下,松籽壳总黄酮得率为15.37mg/g。     

响应面法优化白茅根总黄酮超声辅助提取工艺

以白茅根为原料,利用超声波辅助提取,响应面法优化白茅根总黄酮的提取工艺参数。在单因素试验基础上,选取乙醇体积分数、液料比、超声功率、提取时间为影响因素,用响应面分析法优化白茅根总黄酮的提取工艺条件。结果表明,在乙醇体积分数50%,液料比25∶1(m L/g),超声功率530 W,提取时间30 min的最佳提取工艺条件下,提取到2.18 mg/g的白茅根总黄酮,与理论预测值2.21 mg/g相近。说明采用响应面法优化白茅根总黄酮提取工艺具有可行性。     

响应面优化超声波提取桑叶槲皮素工艺

为优化超声波辅助提取桑叶槲皮素工艺,以桑叶槲皮素提取量为指标,通过单因素试验,探讨液料比、乙醇体积分数、超声时间、超声功率及超声温度等对槲皮素提取量的影响,利用响应面法对影响槲皮素提取量的4个主要因素进行优化,分别为乙醇体积分数、液料比、超声功率、超声温度。结果表明,最佳提取工艺条件为乙醇体积分数51%、液料比26∶1(m L/g)、超声功率200 W、超声温度70℃,在此条件下,做3次平行实验进行验证,桑叶槲皮素提取量为11.13 mg/g,与模型预测值11.31 mg/g基本相符。模型可较好地预测桑叶槲皮素的提取量,响应面法对桑叶槲皮素提取条件参数优化具有可行性。     

响应面法优化超声波辅助提取

采用超声波辅助萃取法提取文冠果种皮中的总皂苷。考察了乙醇体积分数、超声波功率、料液比、提取时间和提取温度对总皂苷提取率的影响,在单因素试验的基础上选取对总皂苷提取率影响显著的料液比、乙醇体积分数和超声波功率,利用Box-Behnken设计原理,以总皂苷提取率为响应值进行响应面试验,建立了回归方程,得到了优化的提取条件（料液比1∶30,乙醇体积分数73%,超声波功率220 W）。在提取温度50℃、提取时间90 min及优化的提取条件下,文冠果种皮总皂苷提取率达0.30%。     

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