四-（对甲基苯基）-卟啉柱前衍生，高效液柱色谱法测定食品中痕量铅、镉、汞

研究了用四-(对甲基苯基)-卟啉柱前衍生，高效液相色谱法测定食品中痕量铅、镉、汞的方法。食品样品用湿法消化后，消化液中的铅、镉、汞用四-(对甲基苯基)-卟啉(T4MPP)柱前衍生，然后用甲醇(内含0．01mol／L四氢吡咯-醋酸缓冲盐)和四氢呋喃(内含0．01mol／L四氢吡咯-醋酸缓冲盐)为流动相梯度洗脱，Waters Xterra^TMRP18(3．9150mm，5μm)色谱柱为固定相分离铅、镉、汞的T4MPP络合物，用二极管矩阵检测器检测，铅、镉、汞含量在0．01～3mg／L范围内与峰面积成线性关系，根据信噪比(S／N=3)，方法检测限为：铅2．3μg／L、镉1．8μg／L和汞2.5μg／L，方法相对标准偏差为2．1％～3．5％，标准回收率为93％～106％，该方法用于测定食品中的铅、镉、汞，结果令人满意。     

用快速分离柱高效液相色谱法测定食品中的重金属元素的研究

研究了用固相萃取富集,快速分离柱高效液相色谱法测定食品中6种重金属元素:镍、铜、锡、铅、镉、汞的方法。食品样品用微波消化,样品消化液中的镍、铜、锡、铅、镉、汞用四-(邻氯苯基)-卟啉(T2CPP)柱前衍生,然后用ZORBAXRP1固相萃取小柱萃取富集镍、铜、锡、铅、镉、汞的T2-CPP络合物,富集8倍数为50倍;经富集后的络合物用甲醇-四氢呋喃(92/8)为流动相,ZORBAXStableBound(4.6×50mm,1.8μm)快速分离柱为固定相分离,用二极管矩阵检测器检测。镍、铜、锡、铅、镉、汞的检测限分别为:3、4、4、3、2、2ng/L,分离6种重金属元素络合物的时间只需2.0min。方法相对标准偏差为2.3%～2.8%,标准回收率为95%～105%。该方法用于测定食品中的痕量镍、铜、锡、铅、镉、汞,结果令人满意。     

电感耦合等离子体质谱法测定食品接触材料中可溶性铅、镉、砷、汞

建立了食品用粘合剂、塑料瓶等高分子食品接触材料中可溶性铅、镉、砷、汞和含量的电感耦合等离子体质谱检测方法.样品中铅、镉、砷、汞的可溶部分溶解在0.07 mol/L的盐酸(模拟人体胃酸)中,·用电感耦合等离子体质谱检测,内标法定量.在0.5μg/L～100μg/L添加水平,回收率在88.6%～98.3%之间,精密度在1.8%～5.1%之间.     

高效液相色谱分析法测定几种煲汤药材金属元素含量

采用四-(对氨基苯基)-卟啉(T4-APP)柱前衍生,以固相萃取富集,利用高效液相色谱法测定四种广东常用煲汤药材(五指毛桃、鸡骨草、海底椰和土茯苓)及其汤底中六种重金属元素:镍、铜、锡、铅、镉、汞的含量。结果表明四种药材均含有一定量的重金属元素,其中以铜含量最高,浓度范围为12.96～37.28μg/g,而汞含量最低为0.07～0.73μg/g;经过长时间煲煮后,汤底中的重金属元素残留比例有所差异,其中镉(Cd)的残留量最高,达到63.97%～76.32%,而铜(Cu)的残留量最低,仅为26.56%～36.67%。土茯苓具有最高含量的铜元素为37.28%,但其锡、铅和汞元素的含量最低,分别为0.69、0.37和0.07μg/g,并且在汤底中的残留比例最高,分别为75.36%、91.89%和85.71%;其它三种药材及其汤底中残留重金属含量相近,没有明显差异。     

2007~2014广东省膳食中铅、镉、砷、汞元素的 人群健康风险评估

目的采用中国总膳食研究方法,运用广东省重金属污染监测工作所采集的各类居民日常食品中的铅、镉、砷、汞检测数据,评估广东省居民膳食中铅、镉、砷、汞的人群健康暴露情况。方法测定广东22市各类食品中的铅、镉、砷、汞含量,计算居民铅的暴露边界比,镉的每月摄入量,砷、汞的每周摄入量并以此作为评价标准。结果各类食品中铅、镉、砷、汞的总体均值分别为0.140、0.118、0.320、0.018 mg/kg,18岁以下未成年人群,铅的暴露边界比(MOE)值为0.35~13.76;18岁以上成年人群,铅的MOE值为1.83~89.57,镉的每月摄入量为0.02~20.28μg/kg.bw,占镉暂定每月可耐受摄人量的0.08%~81.1%。各人群大米中镉的EMI值为11.47~20.28μg/kg·bw,占镉暂定每月可耐受摄入量的45.9%~81.1%;砷的EWI值为0.2~10.4μg/kg·bw,占PTWI的1.3%~69%;汞的EWI值为0.01~1.29μg/kg·bw,占PTWI的0.25%~32.2%。结论广东省居民膳食中铅、镉、砷、汞污染的暴露情况对于各年龄段人群来说总体处于安全水平,但其中大米的镉、蔬菜中的铅暴露却存在一定的风险。     

微波消解-石墨炉原子吸收法测定食品污染物中铅镉的含量

目的探讨微波消解-石墨炉原子吸收法测定食品污染物铅镉的含量。方法采用微波消解技术,在阶梯升高温度和加热功率条件下,用硝酸和过氧化氢彻底消解样品,消解后的样品用石墨炉原子吸收分光光度法测定铅镉。结果铅浓度在0～20.0μg/L、镉浓度在0～10.0μg/L范围内呈良好的线性关系,相关系数铅r=0.9995,镉r=0.9997;最低检出限铅为5.0μg/kg,镉为0.10μg/kg;相对标准偏差铅5.4%,镉7.8%;回收率铅镉都在90.0%～105.0%之间。检测4类食品240份样品,其中大米(面粉)、猪肝(猪肾)、水产品、干食用菌铅合格率分别为86.5%、77.5%、81.5%、87.5%,镉合格率分别为82.0%、76.5%、90.0%、88.0%。结论该方法能够满足食品污染物中铅镉的分析要求。     

高效液相色谱-电感耦合等离子体质谱联用法测定东海乌参样品中的二价汞、甲基汞、乙基汞和苯基汞

目的建立高效液相色谱-电感耦合等离子体质谱法(high performance liquid chromatography-inductively coupled plasma-mass spectrometry,HPLC-ICP-MS)测定东海乌参样品中的二价汞、甲基汞、乙基汞和苯基汞4种汞形态的含量。方法样品经25%KOH微波萃取1 h,采用Agilent Zorbax Plus C_(18)色谱柱分离,以10 mmol/L醋酸铵+0.12%L-半胱氨酸缓冲盐及2%甲醇作为流动相进行梯度洗脱,采用ICP-MS进行检测。结果二价汞、甲基汞、乙基汞和苯基汞在10 min内完成分离,检出限分别为0.8、0.2、0.2和0.8 ng/m L;在0.10、0.20和0.40mg/kg 3个加标水平下,4种汞化合物的回收率为78.1%~105.8%,相对标准偏差为5.3%~8.2%。结论本方法简便、快速、准确,可适用于汞形态的分析。     

微波消解-电感耦合等离子体质谱法测定卡拉胶中的砷、铅、镉、汞含量

采用微波消解-电感耦合等离子体质谱法测定卡拉胶中的砷、铅、镉、汞含量,在试验条件下,砷、铅、镉标准曲线在0～50.0μg.L^-1浓度范围内线性相关系数为0.9998～0.9999,检出限为0.3～0.5μg.kg^-1;汞标准曲线在0～10.0μg.L^-1浓度范围内线性相关系数0.9999,检出限0.3μg.kg^-1;卡拉胶样品中砷、铅、镉、汞加标回收率为91.0%～110%。实验表明,该方法操作简单、灵敏度高、精密度高、检出限低、省时省力,适用于卡拉胶中的砷、铅、镉、汞含量测定     

ICP-AES同时测定可食性包装材料中的铅、砷、镉和汞

以硝酸作为消解液,采用电热消解-电感耦合等离子体原子发射光谱法(ICP-AES)同时测定可食性包装材料中的铅、砷、镉和汞含量。铅、砷、镉和汞的检出限分别为0.150,0.360,0.015和0.135 mg/kg,线性范围为0~2μg/m L,线性关系良好(R0.999),相对标准偏差为1.76%~4.22%,平均加标回收率为82%~108%,该方法的精密度与准确度均满足测试要求,适用于可食性包装材料中铅、砷、镉和汞的同时测定。     

苹果、脐橙中铅和汞的快速测定的方法研究

研究一种简单快速测定苹果和脐橙中铅和汞的方法。在铁氰化钾-酒石酸体系下,用微波消解-原子荧光光谱法快速测定铅和汞的含量。结果表明:在优化的工作条件下,铅和汞的线性范围分别为0~100μg/L和0~2.00μg/mL,检出限分别为0.37μg/L和4.64×10-3μg/L,加标回收率为98.5%和97.1%,相对标准偏差均小于5%(n=11)。该方法具有操作简便、快速、灵敏度高的优点,可作为苹果和脐橙中微量铅和汞快速测定的方法。     

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