ICP-MS法直接测定氢化植物油中的重金属元素

建立了煤油稀释样品,电感耦合等离子体质谱(ICP-MS)法直接测定氢化植物油中Cr、Ni、Cu、As、Cd、Sb、Hg、Pb等8种重金属元素的分析方法。通过向等离子体气中混入20%的氧气以消除有机样品中高碳的影响,详细地研究了在加氧情况下载气流速、等离子体功率和样品提升量对等离子体稳定性的影响,采用碰撞/反应池(CRC)技术校正了多原子离子质谱干扰,选择内标法校正了基体效应。结果表明,8种重金属元素定量标准曲线的线性相关系数不小于0.999 8,检出限在0.13~2.06 ng/g之间,RSD为2.26%~4.81%,加标回收率在91.23%~106.55%之间。方法能满足氢化植物油中重金属元素的分析要求。     

ICP-MS法直接测定食用黄油中的重金属元素

建立了电感耦合等离子体质谱(ICP-MS)法直接测定食用黄油中Cr、Co、Ni、As、Cd、Sb、Hg、Pb等8种重金属元素的分析方法。黄油经正丙醇+二甲苯(70:30,V/V)稀释后直接进入ICP-MS进行分析,有机样品可以长时间保持稳定以满足多元素的测定要求,在等离子气中引入少量氧气,以防止样品溶液中的高碳在质谱采样锥锥口沉积导致分析元素的灵敏度降低。应用ORS技术校正了多原子离子对待测元素产生的质谱干扰,采用Rh为内标元素校正了质谱分析中的基体效应。8种重金属元素的检出限在0.6~22.1 ng/L之间,加标回收率在92.6%~106.0%之间,相对标准偏差(RSD)为1.6%~3.4%。     

高盐食品基质中砷含量的测定

建立了一种基体匹配-动态反应池-电感耦合等离子体质谱法测定高盐食品基质中砷含量的方法,以解决高盐基体对砷测定的质谱干扰和基体干扰。研究电感耦合等离子体质谱法与氢化物发生原子荧光光谱法测定食品中总砷的技术要点,通过分析前处理消解方式、有机基质、氯含量和内标校正元素等对砷含量测定的影响,建立了高盐食品基质中砷含量的测定方法。实验结果表明,微波消解法并不太适用于氢化物发生原子荧光光谱法测定食品中总砷,有机基质和氯分别会对砷的质谱测定信号产生增敏效应和质谱干扰,74Ge比72Ge更适合作为电感耦合等离子体质谱法测定食品中总砷的内标元素。建立的检测方法定量限0.010 mg/kg,高盐基体中砷在0.010、0.025、0.20、0.50 mg/kg添加水平的回收率为91.50%~110.80%,相对标准偏差范围为0.76%~7.22%。本法和参照法对样品分析结果统计值均大于t0.90,10（1.81,双边）,测定结果存在显著性差异,对实际样品测定结果表明动能歧视测定模式并不太适用于高盐食品基质样品中总砷的测定。该方法准确可靠,能用于高盐和高基体食品中砷含量的测定分析。     

碰撞反应池-电感耦合等离子体质谱法测定生姜油中10种重金属元素

建立了碰撞反应池-电感耦合等离子体质谱法测定生姜油中的重金属元素的方法,通过设计3因素(消解温度、消解时间和试剂选择)3水平的正交实验方案确立前处理条件:消解温度180℃、消解时间30 min、硝酸4 mL、过氧化氢2 mL,仪器采用电感耦合等离子体质谱(ICP-MS)-碰撞模式消除质谱干扰,碰撞池He气流速设置为3.2 mL/min,使各元素在背景信号强度降低的情况下,有较低的等效背景浓度(BEC),从而准确地测定了各元素的含量。同时采用45SC、72Ge、115In、209Bi作为内标元素来校正基体带来的干扰,最终确定测定生姜油中Pb、As、Cr、Cu、Fe、Cd、Mn、Ni、Zn、Ba共10种重金属含量的最优条件。     

食品包装材料中重金属的ICP-MS分析

电感耦合等离子体质谱(ICP-MS)是一种具有较强检测能力的无机元素分析方法,在食品包装材料重金属分析中得到较为广泛的应用。本文从样品处理、干扰研究和实际应用3个方面综述了ICP-MS在食品包装材料重金属分析中的应用,对未来发展进行展望。微波消解是最主要的样品处理方法,质谱干扰主要通过干扰方程和碰撞/反应池技术校正。实际应用主要包括材料或制品重金属含量分析、形态分析、粒度分析和迁移分析。随着仪器性能和检测能力的不断提升, ICP-MS将能够在更低浓度水平上进行食品包装材料重金属元素含量分析、形态分析和粒度分析,为确保食品安全和人民群众身体健康发挥更大的作用。     

三乙胺增强-电感耦合等离子体质谱法测定食品中痕量砷

目的 采用三乙胺作为基体改进剂, 实现电感耦合等离子体质谱法(inductively coupled plasma mass spectrometry, ICP-MS)对食品中痕量砷的准确测定。方法 采用微波消解法进行样品前处理, 以8%的三乙胺作为基体改进剂, 采用碰撞池技术规避质谱干扰, 锗作为内标校正非质谱干扰, 用ICP-MS检测样品中的痕量砷。结果 以8%的三乙胺作为基体改进剂, 可以使砷的信号增加14.1倍, 显著地改善方法的精密度和准确度, 方法检出限为0.42 μg/kg。将该方法用于三种生物标准物质(小麦GBW10011、湖南大米GBW10045、芹菜GBW10048)中砷的测定, 测定值均在认定值范围内, 结果的相对标准偏差(relative standard deviation, RSD)为2.5%~5.9% (n=6)。结论 该方法检出限低、准确度和精密度高, 可用于食品中痕量砷的检测。     

食用橄榄油中重金属元素的质谱分析

建立了电感耦合等离子体质谱(ICP-MS)法直接测定橄榄油中Cr、Ni、As、Cd、Hg、Pb等6种重金属元素的分析方法。样品经正丙醇+二甲苯(70:30,V/V)有机溶剂稀释后直接进入ICP-MS进行分析,有机样品可以长时间保持稳定以满足多元素的测定要求,在等离子气中引入少量氧气,以防止样品溶液中的高碳在质谱采样锥锥孔沉积导致分析元素的灵敏度降低。应用碰撞/反应池技术校正了多原子离子对待测元素产生的质谱干扰,采用Rh为内标元素校正了质谱分析中的基体效应。6种重金属元素的检出限在17.58~53.81 ng/L之间,加标回收率在94.00~107.00%之间,相对标准偏差(RSD)为1.33~2.80%。     

鱼油中重金属元素的质谱分析

建立了电感耦合等离子体质谱(ICP-MS)法测定鱼油中Cr、Co、Ni、As、Mo、Cd、Sn、Sb、Hg、Pb等10种重金属元素的分析方法。采用微波消解法消解样品后直接进行分析,应用碰撞/反应池(ORS)技术有效地消除了多原子离子对待测元素的干扰,选用Sc、Rh、Bi等元素为内标混合液校正基体干扰和漂移。结果表明,该方法的检出限为0.008～0.073μg/L,相对标准偏差均小于4.4%,通过添加标准回收实验,回收率在89.6%～103.8%。该法简便、快速,能满足鱼油中多种微量重金属元素同时测定的分析需求。     

碰撞反应池-电感耦合等离子体质谱法检测海藻食品中重金属

目的建立碰撞反应池—电感耦合等离子体质谱法(inductively coupled plasma-mass spectrometry,ICP-MS)测定海藻食品中铬、镍、铜、砷、镉、汞、铅等重金属元素的分析检测方法。方法样品经微波消解后用电感耦合等离子体质谱仪直接进行分析,采用内标元素72Ge、115In和209Bi消除基体干扰和信号漂移,碰撞反应池技术(ORS)消除质谱干扰。结果各元素校正曲线的相关系数均大于0.9992,方法的检出限0.003μg/L~0.028μg/L,相对标准偏差小于4.92%,加标回收率为85.6%~106.2%,标准参考物质的测定结果与标准值相符。结论该方法前处理操作简便快速,灵敏度高,重复性好,适用于海苔、海带、紫菜等海藻食品中多种元素的同时测定。     

ICP-MS法测定食用明胶中重金属元素

利用电感耦合等离子体质谱法(ICP-MS)测定食用明胶中Cr、Mn、Ni、As、Cd、Sb、Hg、Pb等8种重金属元素的分析方法。通过优化仪器的工作参数、选择适宜待测元素的同位素以及选用干扰元素校正方程可以克服质谱干扰,以Sc、Rh、Bi为内标元素,样品的基体效应和仪器漂移得到了很好地校正。结果表明,8种重金属元素的检出限在0.002～0.091μg/L之间,RSD<2.11%,回收率在91.5%～109.0%之间,方法与其他分析对照,结果一致。     

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