凝胶渗透色谱—气相色谱/质谱法测定塑料桶装食用油中四种邻苯二甲酸酯

建立用凝胶渗透色谱净化―气相色谱/质谱分析塑料桶装食用油中四种邻苯二甲酸酯类增塑剂方法。样品用环己烷―乙酸乙酯(体积比为1∶1)稀释,稀释液经Bio–Bead S–X3凝胶柱净化后,采用气相色谱―质谱在选择离子检测(SIM)模式下进行定性定量分析;结果表明,四种增塑剂在0.1 mg/L~5 mg/L范围内线性关系良好;在空白油样中添加四种增塑剂(添加水平为0.5 mg/kg、5 mg/kg、10 mg/kg)混合标准溶液,平均回收率为85.7%~108.2%,相对标准偏差为3.8%~9.2%,检出限为0.1 mg/kg~0.2 mg/kg。     

ASE-GPC-LC/MS/MS联用检测贝类样品中扑草净的残留

建立了ASE(快速溶剂提取)、GPC(凝胶渗透色谱仪)、(液相色谱-质谱联用)LC/MS/MS法检测贝类样品中扑草净残留量的分析方法。本实验采用乙腈经ASE上机提取,凝胶渗透色谱仪净化,最后通过液相色谱-串联质谱进行定量检测。实验结果表明:扑草净在线性范围为0.25~40μg/kg时,线性关系良好(R2=0.9999),回收率为90.0%~105.4%,相对标准偏差2.9%~5.3%。     

GPC净化-GC-MS/MS法测定鳗鱼中杀虫脒、双甲脒及代谢物残留

建立了鳗鱼中杀虫脒及其代谢物4-氯邻甲基苯胺、双甲脒及其代谢物2,4-二甲基苯胺残留的GPC-GC/MS/MS检测方法。样品经环己烷+乙酸乙酯(1+1)均质提取,凝胶渗透色谱净化,采用气相色谱-串联质谱检测,外标法定量。结果表明:4种农药在5~100μg/L质量浓度范围内,组分含量与峰面积呈线性相关,相关系数为0.998 8~0.999 8,4种农药在鳗鱼中不同质量浓度水平的加标回收率分别为74.55%~99.28%,71.09%~96.70%和77.47%~89.42%,相应的相对标准偏差分别为2.52%~4.49%,2.78%~5.27%和0.73%~3.27%(n=6)。方法检出限为0.07~2.0μg/kg。该方法具有检出限低、灵敏度高、快速、准确的特点,可适用于鳗鱼中杀虫脒、双甲脒及代谢物农药残留同时检测。     

气相色谱-三重四极杆质谱法测定液体乳及乳粉中的17种邻苯二甲酸酯类增塑剂

目的建立气相色谱-三重四极杆质谱法(gas chromatography-tandem mass spectrometry,GC-MS/MS)同时测定液体乳及乳粉中17种邻苯二甲酸酯类增塑剂的含量。方法样品经乙腈超声提取,凝胶渗透色谱(gel permeation chromatography,GPC)净化后用GC-MS/MS分析,外标法定量。结果该方法线性关系良好,相关系数为0.9956～0.9999;方法的检出限(S/N=3)为3～60μg/kg;定量限(S/N=10)为10～200μg/kg;在50、200、500μg/kg添加水平下的平均回收率为78.2%～115.4%,相对标准偏差为2.65%～9.95%。结论本研究建立的方法样品处理简单快速、净化效果好、灵敏度和选择性高,适用于日常检测工作。     

气相色谱串联质谱法检测水产品中有机氯和菊酯农药残留

建立利用凝胶渗透色谱-气相色谱-三重四极杆串联质谱仪(gas chromatography-triple quadrupole-tandem mass spectrometry,GC-MS/MS)快速检测水产品中有机氯和菊酯类多种农药残留的方法,对样品提取溶剂进行优化,利用凝胶渗透色谱(gel permeation chromatography, GPC)结合分散固相萃取技术净化样品,并分别对农药化合物在GPC上的收集时间参数和N-丙基乙二胺(primary secondary amine,PSA)固相萃取吸附剂的添加量进行优化,在电子轰击电离源下进行多反应监测(multiple reaction monitoring,MRM)采集,该方法的检出限(limits of detection,LOD)为0.03 μg/kg^2.87 μg/kg,试验结果表明,该方法的回收率为60.5 %~118 %,相对标准偏差为0.75 %~15 %,该方法重现性好,精密度高,适用于泥鳅等水产品中有机氯和菊酯类农药残留的检测。     

凝胶色谱-液相色谱串联质谱法测定植物油中胆固醇含量

以植物油脂为试验材料,建立了凝胶渗透色谱-液相色谱串联质谱法(GPC-HPLC-MS/MS)测定植物油脂中胆固醇含量。样品经凝胶渗透色谱净化后,采用液相色谱串联质谱法(HPLC-APCI-MS/MS)分析,多反应监测模式下(MRM)外标法定量。结果表明:方法在50.0~1 000.0μg/L范围内线性良好,线性相关系数r为0.999,定量限为0.25 mg/kg,回收率范围为76%~89%,相对标准偏差小于15%。该方法前处理过程简便快捷,回收率高,可满足实验室大量、快速分析的需求。     

凝胶渗透色谱净化联合气相色谱-串联质谱法同时测定番石榴中3种农药残留

目的建立一种同时测定番石榴中3种常用农药的凝胶渗透色谱净化联合气相色谱-串联质谱法(gel permeation chromatography-gas chromatography-tandem mass spectrometry,GPC-GC-MS/MS)分析方法。方法番石榴样品经乙腈提取,凝胶渗透色谱净化,毛细管气相色谱柱分离后,采用三重串联四极杆多反应监测模式测定。结果 3种农药在0.05~0.50 mg/L范围内线性关系良好,相关系数均不低于0.9990;毒死蜱、克螨特、氟氯氰菊酯的定量限分别为0.002、0.005、0.01 mg/kg;在0.05、0.10、0.50 mg/kg 3个加标水平下,3种农药的回收率在83.3%~104.8%之间,相对标准差为2.9%~7.9%。结论该方法处理简便,能满足番石榴中3种常用农药毒死蜱、克螨特、氟氯氰菊酯残留检测的要求。     

液质联用技术检测紫薯蓣中5种氨基甲酸酯农药的方法研究

通过超高液相色谱-串联质谱联用(LC-MS/MS)技术,建立了一种高灵敏度检测紫薯蓣中农药残留的方法。样品经环己烷-乙酸乙酯(1∶1,V/V)提取,全自动凝胶净化在线浓缩仪净化,然后采用LC-ESI(+)-MS/MS测定,对液质分离条件进行优化。实验结果表明,5种氨基甲酸酯农药在1.0~50.0μg/L范围内线性关系良好,相关系数0.9983~0.9999;在2.0~10.0μg/kg浓度范围内,加样回收率82.05%~97.27%之间,相对标准偏差2.85%~6.63%。该方法具有快速、准确、简便、灵敏、净化效果好、人为误差小的特点。     

凝胶渗透色谱-高效液相色谱法测定蔬菜中 呋喃丹的含量

目的建立凝胶渗透色谱-高效液相色谱法检测蔬菜中的呋喃丹农药残留量。方法样品经乙腈提取和环己烷-乙酸乙酯溶解后,经凝胶渗透色谱净化和反相高效液相C_(18)色谱柱分离后,采用荧光检测器进行测定,荧光检测激发波长为285 nm,发射波长为320 nm,采用高效液相色谱法以外标法定量。结果呋喃丹在0.2~5.0 ng/mL浓度范围内呈良好线性关系,相关系数r大于0.999,检测限为0.01 mg/kg。对空白蔬菜样品进行呋喃丹3个浓度水平0.5、1.0和2.0 mg/kg的加标,回收率结果为78.3%~97.6%,相对标准偏差为3.26%~11.69%。结论本研究所建立的方法简单、灵敏度高,可适用于蔬菜中的呋喃丹农药残留的分析检测。     

凝胶渗透色谱净化-超高效液相色谱-串联质谱法测定海带中扑草净残留量

目的 建立凝胶渗透色谱(gel permeation chromatography, GPC)净化-超高效液相色谱-串联质谱(ultra performance liquid chromatography-tandem mass spectrometry, UPLC-MS/MS)法测定海带中扑草净残留量的分析方法。方法 样品用乙腈超声提取, 经凝胶渗透色谱净化, 收集15~35 min的流出液并进行浓缩, 通过超高效液相色谱柱分离后进行质谱检测。结果 称样量为2 g时, 最佳提取条件为10 mL乙腈超声提取时间10 min; 在添加量为0.05~2.66 μg/kg范围时, 扑草净平均回收率为100.1%~102.1%, 相对标准偏差(relative standard deviation, RSD)为1.6%~2.6% (n=6); 方法检出限为0.15 μg/kg; 并将GPC与HLB、Carb-NH2固相萃取进行净化效果比较, 结果表明GPC净化更适用于海带中扑草净的净化。结论 该方法简便、快速、灵敏度高、重复性好, 可用于测定海藻类样品的扑草净残留。     

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.     

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.     

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.     

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.     

Textural Properties of Cold-set Gels Induced from Heat-denatured Whey Protein Isolates

A 9% whey protein (WP) isolate solution at pH 7.0 was heat-denatured at 80°C for 30 min. Size-exclusion HPLC showed that native WP formed soluble aggregates after heat-treatment. Additions of CaCl2 (10–40 mM), NaCl (50–400 mM) or glucono-delta-lactone (GDL, 0.4–2.0%, w/v) or hydrolysis by a protease from Bacillus licheniformis caused gelation of the denatured solution at 45°C. Textural parameters, hardness, adhesiveness, and cohesiveness of the gels so formed changed markedly with concentration of added salts or pH by added GDL. Maximum gel hardness occurred at 200 mM NaCl or pH 4.7. Increasing CaCl2 concentration continuously increased gel hardness. Generally, GDL-induced gels were harder than salt-induced gels, and much harder than the protease-induced gel.     

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.     

Occurrence of bisphenol-F-diglycidyl ether (BFDGE) in fish canned in oil

The levels of bisphenol-F-diglycidyl ether (BFDGE) were quantified as part of a European survey on the migration of residues of epoxy resins into oil from canned fish. The contents of BFDGE in cans, lids and fish collected from all 15 Member States of the European Union and Switzerland were analysed in 382 samples. Cans and lids were separately extracted with acetonitrile. The extraction from fish was carried out with hexane followed by re-extraction with acetonitrile. The analysis was performed by reverse phase HPL C with fluorescence detection. BFDGE could be detected in 12% of the fish, 24% of the cans and 18% of the lids. Only 3% of the fish contained BFDGE in concentrations considerably above 1mg/kg. In addition to the presented data, a comparison was made with the levels of BADGE (bisphenol-A-diglycidyl ether)analysed in the same products in the context of a previous study.     

Contribution of European research to risk analysis

The European Commission's, Quality of Life Research Programme, Key Action 1—Health, Food & Nutrition is mission-oriented and aims, amongst other things, at providing a healthy, safe and high-quality food supply leading to reinforced consumer confidence in the safety of European food. Its objectives also include the enhancing of the competitiveness of the European food supply. Key Action 1 is currently supporting a number of different types of European collaborative projects in the area of risk analysis. The objectives of these projects range from the development and validation of prevention strategies including the reduction of consumers risks; development and validation of new modelling approaches; harmonization of risk assessment principles, methodologies, and terminology; standardization of methods and systems used for the safety evaluation of transgenic food; providing of tools for the evaluation of human viral contamination of shellfish and quality control; new methodologies for assessing the potential of unintended effects of genetically modified (genetically modified) foods; development of a risk assessment model for Cryptosporidium parvum related to the food and water industries; to the development of a communication platform for genetically modified organism, producers, retailers, regulatory authorities and consumer groups to improve safety assessment procedures, risk management strategies and risk communication; development and validation of new methods for safety testing of transgenic food; evaluation of the safety and efficacy of iron supplementation in pregnant women; evaluation of the potential cancer-preventing activity of pro- and pre-biotic ('synbiotic') combinations in human volunteers. An overview of these projects is presented here.