便携式能量色散X射线荧光光谱法快速检测玩具中5种元素

本文研究并建立了便携式能量色散X射线荧光光谱仪直接快速测定玩具样品中铅、镉、铬、汞、砷含量的分析方法。方法精密度实验表明,各元素相对标准偏差(RSD,n=11)在1.59%~6.21%之间,铅、汞、砷的检测限均小于2 mg/kg,镉、铬的检测限小于3 mg/kg。方法用于塑料类和皮革类玩具样品分析,测定结果与湿法分析结果一致,能够满足实际样品铅、镉、铬、汞、砷元素同时快速分析的要求。     

X-射线荧光光谱法快速测定谷物碾磨加工品中的重金属

目的 本研究利用X-射线荧光光谱法原理建立了一种谷物碾磨加工品中铅、总砷、镉、铬、总汞的快速检测方法。方法 选择谷物碾磨加工品中小麦粉典型基质,制备成含有一定量5种重金属标准样品,利用标准样品对检测时样品的粒径、装样质量、装样压力等检测条件进行优化,并对检测方法线性范围、定量限、精密度、重复性、稳定性等方法学进行考察。结果 检测方法中铅、总砷、镉定量限为0.1mg/kg,铬定量限为0.5mg/kg,总汞定量限为0.05mg/kg;线性范围铅、总砷、镉约为0.1mg/kg~2mg/kg,铬约为0.5mg/kg~9mg/kg,总汞约为0.05mg/kg~2mg/kg,线性相关系数(R2)均大于0.99;方法精密度、重复性、稳定性相对偏差均小于15%,对X-射线荧光光谱法与国检测结果进行比较,相对误差小于15%。结论 本研究建立的方法简便、快捷、准确性高,适宜对谷物碾磨加工品中5种重金属进行快速检测。     

波长色散型X射线荧光光谱法测定进出口皮革制品中重金属含量

本文研究并建立了波长色散X射线荧光光谱法(WDXRF)直接快速测定皮革制品中铅、镉、铬、汞、砷含量的分析方法,并考察了方法的检测精密度和准确度.实验结果表明,各元素相对标准偏差(RSD,n=11)在1.86％～6.21％之间,铅、汞、砷的检测限均小于0.2 mg/kg,镉、铬的检测限小于0.5 mg/kg.并同湿法消解...     

X射线荧光光谱法检测粮食中镉元素的应用探讨

以石墨炉原子吸收法测定值为粮食中镉元素含量参考标准值,用能量色散型X射线荧光光谱法检测粮食中镉元素。比较两种方法检测结果,对应用能量色散型X射线荧光光谱法进行粮食中镉元素快速筛查的应用性进行了探讨。共检测1 000个稻谷样品、257个小麦样品、42个玉米样品,检测结果显示,样品中,稻谷镉含量主要在0.05～0.20mg/kg,小麦主要在0.05～0.15mg/kg,玉米主要在0.05mg/kg及以下;稻谷和小麦两种方法检测结果呈极显著相关,两种方法测定结果偏差0.05mg/kg及以内的样品占95%以上,少部分样品偏差在0.06～0.08mg/kg。应用X射线荧光光谱法,稻谷、小麦、玉米误判率分别为0.7%、12%和0,镉含量在污染物限量临界值上下0.05mg/kg及以内时,存在一定比例的假阴或假阳性结果,应重点监控。能量散射型X射线荧光光谱法能满足一定条件下粮食的快速筛查需求,稻谷适用性最高。建议快检法与国标法结合使用。     

X射线荧光光谱法与国标法检测稻谷中镉的比较研究

抽取稻谷样品,用X射线荧光光谱法与国标法(石墨炉原子吸收法)对稻谷中的镉含量进行检测,比较两种方法测定结果的差异,为采用X射线荧光光谱法作为稻谷中镉测定的快检方法提供数据支撑。精密度对比实验结果表明,X射线荧光光谱法精密度好。抽样比对结果为:抽检886个样品,两种方法的测定值分别在0.05～0.67 mg/kg、0.01～0.60 mg/kg之间,偏差在0.08 mg/kg及以内,其中偏差在0.05 mg/kg及以内的样品占96%,0.06～0.08 mg/kg的样品占4%;当样品含量在0.12 mg/kg及以上时,通过配对样本T检验显示两种方法所测数据在显著性水平为0.05时无显著差异性。     

钢衬F4高压密闭消解在测定粮食及其制品中有害元素铅、镉、汞、砷、铝的应用

建立了钢衬F4高压密闭消解结合光谱设备来测定粮食中有害元素铅、镉、汞、砷、铝的方法,采用钢衬F4高压消解罐对稻谷、小麦、挂面、豆制品、小麦粉等粮食及其制品进行消解,研究了消解不同样品的用酸量和消解温度,称样量最高可达2.0 g,大大降低了检出限,其中汞和镉的检出限分别达到0.002和0.01 mg/kg。回收率在85%～110%,对于挥发性元素也有较好的回收率,分析结果的精密度、检出限、定量限及准确度令人满意。     

能量色散X射线荧光光谱仪在稻米中镉含量测定的应用研究

目的研究能量色散X射线荧光光谱仪(X-ray fluorescence spectrometers,XRF)在稻米中镉元素快速测定中应用,验证评价该仪器是否满足筛查稻米样品中镉含量的实际需求。方法选择不同厂家典型X射线荧光光谱仪,采用实际样品分别评估其定性和定量检出限,批量样品评估检测效率以及定期稳定性等。考察稻米不同形态(糙米和精米)、测定时间和测定次数对X射线荧光光谱仪测定稻米中镉含量的影响,同时比较不同品牌仪器间的差异性。结果 2台XRF仪器的筛查定量限均小于稻米中镉的限量值0.2 mg/kg。工作曲线线性关系(r2)大于0.99,测量相对偏差小于20%,150 d内定期稳定性监测的变异系数小于3%。单次测量时间小于20 min,批量样品检测时间较长。结论能量色散X射线荧光光谱仪灵敏度能够满足实际稻米样品中镉元素污染的快速筛查要求;稻米的不同形态对X射线荧光光谱仪的检测结果无显著性影响;随着测定时间和测定次数的增加,XRF方法的检测结果与实际量值更接近;存在不同程度的假阴和假阳问题。     

GC-MS/MS法快速检测小麦粉中8种农药残留

目的:建立QuEChERS-气质联用法检测小麦粉中8种农药残留的方法。方法:混匀后的小麦粉样品经乙腈提取,QuEChERS浓缩净化,以8种农残的特征碎片离子建立气质联用检测条件,外标法定量。结果:在0～1μg/mL浓度范围内,线性关系良好,检出限0.005～0.02 mg/kg,定量限0.02～0.06 mg/kg,回收率70.2～90.6%,精密度2.1～4.7%。结论:该方法操作简便、定性定量准确、灵敏度高,适合小麦粉中农药残留的检测。     

糊化制样X射线荧光光谱法快速检测鲜香菇中的铅、砷、镉

建立糊化制样能量色散X射线荧光(energy-dispersive X-ray fluorescence, EDXRF)光谱快速检测鲜香菇中铅(lead, Pb)、砷(arsenic, As)和镉(cadmium, Cd)的新方法。方法 鲜香菇样品与稀硝酸水溶液均质糊化后, 直接进行EDXRF光扫描, 通过谱峰识别进行定性, 以加标校正曲线进行定量。结果 样品基质中待测元素谱峰无干扰, 方法线性良好(r2≥0.995); Pb、As和Cd的检出限分别为0.34、0.14和0.19 mg/kg, 定量限分别为1.15、0.47和0.63 mg/kg; 总体加标回收率为93.7%~105.8%, 相对标准偏差为0.92%~20.60%; 以食品安全限量为关注浓度, 应用本方法进行合格性快筛, Pb、As和Cd含量在关注浓度及以上时阳性检出率为100%, 在0.2 mg/kg及以下时, 假阳性检出率小于等于10%, 符合快速检测方法的要求。结论 该方法操作简单、快速和绿色无污染, 可为食用菌产品的质量控制和检测提供有效的方法借鉴。     

X射线荧光光谱结合基本参数法快速测定食品中砷、镉、铅元素含量

目的 建立一种基于X射线荧光光谱仪(X-Ray Fluorescence Spectrometry, XRF)结合快速基本参数法快速测定不同食品样品中砷、铅、镉元素的分析方法。方法 样品粉碎过筛后,压片制备,用XRF结合基本参数法进行定量分析和快速筛查分析。结果 XRF方法的As、Cd、Pb检出限分别为:0.07、0.06、0.07 mg/kg。在国标GB 2762—2017规定的食品限量浓度水平,As、Cd、Pb的XRF检测结果和电感耦合等离子体质谱法检测结果相比相对相差值均小于25%。针对谷物、豆类、肉制品、水产品样品的XRF快速检测,除个别食品类别外,As、Cd和Pb元素的假阳性率和假阴性率均小于5%。结论 该方法具有操作简单、检测快速、灵敏度高等特点,适用于食品中砷、镉和铅的现场、快速筛查分析。     

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.     

Chlorohydrins of bisphenol A diglycidyl ether (BADGE) and of bisphenol F diglycidyl ether (BFDGE) in canned foods and ready-to-drink coffees from the Japanese market

BADGE.2HCl and BFDGE.2HCl were determined in 28 samples of ready-to-drink canned coffee and 18 samples of canned vegetables (10 corn, 5 tomatoes and 3 others), all from the Japanese market. HPLC was used as the principal analytical method and GCMS for confirmation of relevant LC fractions. BADGE.2HCl was found to be present in one canned coffee and five samples of corn, BFDGE.2HCl in four samples of canned tomatoes and in one canned corn. No sample was found which exceeded the 1mg/kg limit of the EU for the BADGE chlorohydrins. However the highest concentration was found for the sum of BFDGE.2HCl and BFDGE.HCl.H₂O at a level of 1.5mg/kg. A Beilstein test confirmed that all cans containing foods contaminated with BADGE.2HCl or BFDGE.2HCl had at lest one part coated with a PVC organosol.     

European priorities for research to support legislation in the area of food contact materials and articles

A strong science base is required to underpin the planning and decision-making process involved in determining future European community legislation on materials and articles in contact with food. Significant progress has been made in the past 5 years in European funded work in this area, with many developments contributing to a much better understanding of the migration process, and better and simpler approaches to food control. In this paper this progress is reviewed against previously identified work-areas (identified in 1994) and conclusions are reached about future requirements for R&D to support legislation on food contact materials and articles over the next 5 or so years.     

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