花菇多糖的提取工艺优化

采用中心组合实验对花菇水溶性和碱溶性多糖的提取工艺进行了优化。实验结果表明：花菇水溶性多糖的最佳提取条件为提取温度94．34℃，提取时间为3．5h，料液比为1：61．88，在此条件下花菇中水溶性多糖得率最高达到6．78％；花菇碱溶性多糖的最佳提取条件为碱NaOH浓度为1．816mol／L，提取时间为1．7h，料液比为1：60，此时花菇中碱溶性多糖得率最高可达到3．95％。     

响应面法优化牛大力碱溶性多糖的提取工艺

以牛大力为原料提取碱溶性多糖,比较NaOH浓度、浸提温度、浸提时间、液料比以及提取次数对碱溶性多糖提取率的影响,并以NaOH浓度、温度、时间、液料比为考察因素,基于单因素试验结果,采用RSA响应面分析法优化提取工艺。结果表明,液料比对牛大力碱溶性多糖提取率影响最大,其次是浸提时间和NaOH浓度,浸提温度对牛大力碱溶性多糖提取率影响最小。确定碱溶性多糖提取的最佳工艺参数,即NaOH浓度5.2%、温度61℃、时间2.3 h、液料比34∶1 (mL/g)。在此优化工艺下碱溶性多糖提取率为15.91%,与响应面预测值15.76%拟合良好。     

响应面法优化赤灵芝中碱溶性多糖的提取工艺

以赤灵芝为原料提取碱溶性多糖,比较了浸提时间、温度、NaOH浓度、液料比及提取次数对碱溶性多糖提取率的影响,并以浸提时间、温度、NaOH浓度以及液料比为考察因素,采用RSA响应面分析法,确定了碱溶性多糖提取的最佳工艺参数,即液料比20mL/g,浸提温度60℃,浸提时间2h,NaOH质量浓度5%。在此优化工艺下碱溶性多糖提取率预测值为19.63%,验证实验中实际测得碱溶性多糖提取率为19.61%,预测值与实际值无显著差异。     

碱溶性油茶籽饼粕多糖的提取工艺研究

采用油茶籽饼粕为原料,先用热水浸提,再进一步用减法提取碱溶性油茶籽饼粕多糖,应用正交试验优化碱溶性油茶籽饼粕多糖的提取工艺。在单因素分析的基础上,研究不同料液比、温度、碱浓度、时间对多糖得率的影响。结果表明：碱溶性油茶籽饼粕多糖提取的最佳工艺条件是料液比为1：30,提取温度为90℃,碱浓度为0.4mol.L-1,提取时间为2h。在此条件下多糖得率达到8.25%。     

米糠多糖的提取条件及其沉淀特性研究

研究不同的提取温度，提取时间和提取pH值等对米糠多糖提取率的影响。采用响应面分析的方法得到米糠多糖的最佳提取条件为：温度80．5℃，时间1.3h,pH值4．93。并在此基础上，比较了乙醇质量分数和提取液pH对米糠多糖沉淀特性的影响。     

米糠半纤维素提取工艺参数的研究（Ⅰ）

以工业脱脂米糖为原料提取米糠水溶性半纤维素及碱溶性半纤维素，是米糠综合利用的又一有效途径。提出了适合于工业化生产的分步提取途径。研究结果表明：水溶性半纤维素的最佳提取工艺参数为：料液比为１：１０，３ｈ，６０℃；碱溶性半纤维提取工艺参数为：料液比为１：１０，４ｈ，２５℃，碱液浓度为１．０Ｎ。在上述工艺条件下，水溶性半纤维素和碱溶性半纤维素的提取率分别为１．４３％和９．０２％《     

碱溶性菜籽多糖的提取条件优化及体外抗氧化活性研究

本实验采用氢氧化钠提取菜籽饼粕中的多糖,选定提取温度、浸提液浓度、提取时间三因素三水平进行中心组合试验,建立了菜籽多糖提取的二次回归方程。通过SAS软件做响应面分析以及岭嵴分析得到菜籽多糖氢氧化钠提取的最佳条件。试验结果表明,当提取工艺条件为:提取温度93.7℃,浸提液浓度1.124mol/L,提取时间2.3h,其多糖含量为11.59%。并对碱溶性菜籽多糖进行了体外抗氧化活性研究,表明菜籽多糖有一定抗氧化生物活性。     

茯苓多糖的提取及其结构表征

比较水提、酶解水提等提取方法对水溶性多糖提取率的影响;以提取温度、碱浓度、酶活力作为影响因素进行正交试验设计,并用苯酚－硫酸法测定所提多糖的多糖含量,确定茯苓碱溶性多糖的最佳提取方法。采用纸层析分析、红外光谱等方法表征所提多糖的结构。     

碱溶性银耳粗多糖的提取及其清除自由基作用的研究

本实验研究了碱溶性银耳粗多糖(crude alkai-soluble tremella polysaccharide,CATP)的提取及其清除自由基的作用。利用响应面软件进行实验设计,确定最佳提取方案为:提取时间3.56h,NaOH浓度0.76mol/L,液固比81.89。同时考察了碱溶性银耳粗多糖和水溶性银耳粗多糖(tremella polysaccharide,TP)对DPPH(二苯代苦肼基自由基)、羟基自由基、超氧自由基的清除作用。结果表明,碱溶性银耳粗多糖具有良好的抗氧化能力,并且随着多糖浓度的增高抗氧化性增强。     

猴头菌细胞壁多糖的提取和其结构特征

以猴头菌子实体残渣为试验材料,研究了残渣粉粹时间及提取用溶剂对其细胞壁多糖提取得率和结构特征的影响。研究发现粉碎时间延长可增加水溶性细胞壁多糖的得率,但多糖含量会降低,粉粹时间对水溶性细胞壁多糖的绝对重均分子质量分布及单糖组成影响较大,最佳粉碎时间为15 min。Na OH浓度的增加可提高碱溶性细胞壁多糖的得率和含量,但免疫活性降低,最适的Na OH浓度为0.5 mol/L。粉碎水提、碱提两种方式得到的细胞壁多糖均能够显著刺激小鼠巨噬细胞释放NO,具有较好的体外免疫活性;比较水溶性细胞壁多糖与碱溶性细胞壁多糖的结构差异,发现水溶性细胞壁多糖绝对重均分子质量远大于碱溶性细胞壁多糖。碱溶性细胞壁多糖只含有葡萄糖,而水溶性细胞壁多糖还含有一定量的半乳糖,且葡萄糖与半乳糖之间的摩尔比值约为4∶1。优选获得了猴头菌细胞壁多糖的高效制备方法,明确了猴头菌水溶性与碱溶性细胞壁多糖结构特征间的差异。     

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