胡萝卜及其制品中棒曲霉素测定方法的研究

该文对胡萝卜制品中棒曲霉素的分析检测方法进行了研究,建立了以液-液萃取为前处理方法,采用高效液相色谱(HPLC)分析了胡萝卜制品中棒曲霉素.主要研究结果如下:通过对乙酸乙酯提取次数、净化次数、水分含量、干燥时间的研究,优化了传统的液-液萃取测定棒曲霉素的方法.该方法处理和测定棒曲霉素回收率好,而且对胡萝卜样品和胡萝卜浆(或汁)均适用.胡萝卜样品的回收率为86.6％～98.3％;胡萝卜汁样品的回收率为86.8％～99.1％,相对标准偏差≤4.2％.     

冷阱捕集-GC/MS法同时检测卷烟主流烟气中的环氧乙烷和环氧丙烷

为同时准确测定卷烟主流烟气中环氧乙烷和环氧丙烷,建立了冷阱捕集-气相色谱/质谱联用(GC/MS)方法。采用剑桥滤片捕集卷烟主流烟气粒相物,在低温冷阱条件下用甲苯捕集主流烟气气相物,利用GC/MS检测主流烟气气相物中环氧乙烷和环氧丙烷的释放量,对21种国内外不同焦油量卷烟主流烟气中的环氧乙烷和环氧丙烷进行了测定。结果表明:1该方法线性良好(R2≥0.999 7),环氧乙烷和环氧丙烷的检测限分别为0.03μg/支和6.8 ng/支,回收率在91.0%～101.5%之间,日内、日间精密度在2.4%～6.0%之间。221种卷烟样品主流烟气中环氧乙烷和环氧丙烷的释放量分别为1.4～17.8μg/支和158.8～1153.0 ng/支。该方法操作简单、结果准确可靠,适合于同时测定卷烟主流烟气中环氧乙烷和环氧丙烷的释放量。     

高效液相色谱串联质谱测定小麦粉及制品中的氨基脲

建立了高效液相色谱串联质谱测定小麦粉及制品中氨基脲的定性、定量分析方法.首先将样品在酸性条件下进行水解,再用邻硝基苯甲醛衍生,HLB固相萃取柱净化,最后用内标法定量.试验结果显示,小麦粉及制品中氨基脲检出限能达到0.5 μg/kg,工作曲线均呈良好线性,相关系数r＞0.99,回收率为90.0％～98.0％,相对标准偏差6.4％～8.6％,表明该方法能对小麦粉及制品中的氨基脲进行准确地定量分析.     

纺织品中苯乙酮增塑剂的检测方法

建立了测定纺织品中苯乙酮增塑剂的气相色谱-质谱法.样品使用甲基叔丁基醚在超声波中萃取,萃取液过滤、合并、浓缩后净化,进行气相色谱-质谱分析.结果显示,该方法检出限为0.3 mg/kg,定量限为0.9 mg/kg.对样品进行3组浓度水平的加标测定(N=6),平均回收率为80％ ～ 120％,相对标准偏差(RSDr)≤8％.在0.64 ～ 82 mg/kg范围内线性关系良好,相关系数r =0.9999.该方法简便、快速、准确,可应用于纺织品中苯乙酮增塑剂含量的测定.     

顶空–气相色谱法测定芝麻和茶叶中环氧乙烷的残留量

环氧乙烷常用于食品杀菌剂,且极易在食品中造成残留,目前我国暂无可用于食品中环氧乙烷含量测定的相关标准。为解决进出口食品中环氧乙烷残留量测定问题,建立了顶空–气相色谱法测定食品中环氧乙烷的残留量的快速方法。对芝麻、茶叶等食品基质中环氧乙烷的提取条件参数进行正交优化,结果表明：使用二甲基乙酰胺溶剂超声提取方法最佳,提取温度对环氧乙烷的回收率影响最为显著,超声功率和时间次之,最佳提取条件为温度40℃,超声功率200 W,时间30 min,回收率最高为89.25%。使用HP-PLOTQ气相色谱柱,在载气最佳流速为2 mL/min时环氧乙烷的分离效果最好,且峰形对称无拖尾。在方法测定条件下,环氧乙烷在0.01～1.0mg/L浓度范围内线性良好,相关系数为0.999,相对标准偏差RSD≤2.96%,总体回收率介于76.9%～91.6%之间,能够满足食品中环氧乙烷含量检测的要求。该方法实验流程简单,可快速对食品中的环氧乙烷进行检测及定量。     

ICP-MS法测定纺丝油剂中总铅含量的研究

文章利用ICP-MS建立了纺丝油剂中总铅含量检测方法,得到了测试浓度范围为4～200μg/L,相关系数R为0.9999的标准曲线,测得方法回收率大于80％,4种纺丝油剂样品中总铅含量为0.25～7.0 mg/kg.本测试方法可为环保、纺织及印染等企业测定纺丝油剂中总铅含量提供一定的参考.     

微波消解—原子荧光光谱法同时测定皮革中的砷和锑

建立了皮革及其制品中砷和锑的微波消解-原子荧光光谱测定方法,方法准确、灵敏,快速.在优化的试验条件下,砷浓度在0.5～150 ng/mL范围内成线性关系,相关系数r=0.9995,检出限为0.22 ng/mL,回收率为99.4％～104.2％:锑浓度在0.5～ 120 ng/mL范围内成线性关系,相关系数r=0.9998,检出限为0.16 ng/mL,回收率为101.1％～106.7％.相对标准偏差(n=5)均小于5％.方法应用于皮革及其制品中砷和锑的测定,结果满意.     

钛胶RP-HPLC法测定食用油及其制品中的TBHQ、PG和BHT

建立了反相钛胶柱高效液相色谱法同时测定油脂及其制品中特丁基对苯二酚(TBHQ)、没食子酸丙酯(PG)和2,6-二叔丁基对甲酚(BHT)的方法.色谱条件:分离柱为Titania Sachtopore-RP柱(250 mm×4.6 mm i.d.,5μm);流动相采用1.0％的磷酸-甲醇-水梯度洗脱;流速为0.8 mL/min;检测波长为290 nm;TBHQ、PG的线性回归范围为0.5～50 μg/mL;BHT线性回归范围为0.5～ 100 μg/mL;TBHQ、PG和BHT的最低检出限分别为0.2、0.1和2.0 μg/mL;样品的加标回收率范围为91.61％ ～ 114.11％.该方法操作简单易行,方法精密度和准确度高,用于食用油及其制品中TBHQ、PG和BHT的同时测定,取得满意结果.     

纺织品中邻苯二甲酸酯类增塑剂含量的测定

采用固相萃取方法（SPE）净化样品，用GC．MSD法测定及确证纺织材料中邻苯二甲酸酯类增塑剂含量。纺织材料试样经三氯甲烷超声波提取，提取液浓缩后用固相萃取净化，采用气相色谱-质谱仪（GC-MSD）测定，外标法定量，选择离子监测进行阳性确证。当添加邻苯二甲酸酯类增塑剂浓度为100～1000mg／kg时，该方法回收率为78％～108％，相对标准偏差为4．26％～9．89％，测定低限为10-50mg／kg，各项指标均满足有关要求。     

纺织制品及助剂中禁用乙二醇醚类物质的测定

建立了纺织制品及助剂中乙二醇醚有机溶剂的测定方法。采用气相色谱-质谱联用仪和DB-Wax色谱柱进行分析，各组分分离效果较好，8种乙二醇醚呈现良好的线性关系。该方法的平均回收率为79.58%～87.77%，相对标准（RSD）为3.07%～6.99%，具有灵敏、准确、分离效果好的优点，适用于纺织制品及助剂中禁用乙二醇醚类物质的检测。     

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