液相色谱-串联质谱同位素稀释法测定奶粉中双氰胺的残留

目的 建立并优化高压液相色谱-串联质谱法快速检测奶粉中双氰胺残留的方法。方法 奶粉样品经1%三氯乙酸溶液沉淀蛋白后, 通过Sep-pak AC-2离子交换固相萃取柱净化样品提取液, 去除奶粉中其他复杂基质的干扰, 浓缩后用初始流动相复溶、过膜。采用电喷雾正离子电离(ESI+)模式和多反应监测(MRM)扫描模式, 通过Acquity BEH Amide(3.0 mm×150 mm, 1.7 μm)色谱柱分离检测双氰胺目标化合物, 同位素15N4-双氰胺稀释法定量。结果 该方法在50~1200 μg/kg范围内线性良好, 相关系数r>0.998, 在三种不同基质样品中的最低检测限与最低定量限分别为2.5 μg/kg和8 μg/kg, 加标回收率为93.4%~112.3%, 相对标准偏差均<10.3%。结论 该方法简便、灵敏、精确, 不仅筛选优化了液相、质谱条件参数, 同时优化了奶粉样品的前处理方法, 适用于奶粉中双氰胺残留的检测。     

同位素稀释超高效液相色谱-串联质谱法测定山楂及其口服液制品中的展青霉素

目的 建立同位素稀释超高效液相色谱-串联质谱法测定山楂及其制品中的展青霉素含量。方法 山楂口服液(山楂样品需经粉碎、果胶酶酶解处理, 乙酸乙酯提取浓缩后复溶)经多功能净化柱净化, 以乙腈-水为流动相梯度洗脱, 采用Agilent RRHD C₁₈柱(2.1 mm×100 mm, 1.8 μm), 电喷雾离子源负离子, 多反应离子监测模式(MRM)检测, 同位素稀释内标法定量。结果 展青霉素在4.934~246.7 ng/mL浓度范围内线性关系良好, 相关系数r大于0.999。在不同基质不同加标浓度下, 回收率为91.8%~105.4%, 相对标准偏差为1.8%~3.2%, 山楂检出限为3 μg/kg、定量限为10 μg/kg, 山楂口服液检出限为1.5 μg/kg、定量限为5 μg/kg。结论 该方法准确、可靠, 适用于山楂制品中展青霉素的测定。     

同位素内标-高效液相色谱-串联质谱法检测牛奶及奶粉中黄曲霉毒素M1

目的 建立一种高效液相色谱-串联质谱法(high performance liquid chromatography-tandem mass spectrometry, HPLC-MS/MS)测定奶及奶粉中黄曲霉毒素M1的方法。方法 样品经甲醇溶液提取后, 经离心机离心, 上层清液用MycoSep?226 AflaZon+Multifunctional净化柱净化, 在线添加黄曲霉毒素M1同位素内标后采用LC-MS/MS进行检测。结果 黄曲霉毒素M1在0.05~5.0 μg/L范围内线性关系良好, 相关系数大于0.995; 在0.02、0.05和0.10 μg/L添加水平的回收率为89.02%~118.85%, 相对标准偏差小于7.06%(n=6), 定量限为0.06 μg/kg。结论 该方法快速、准确、灵敏, 适合用于测定奶及奶粉中黄曲霉毒素M1。     

超高效液相色谱-串联质谱法同时测定食品中的氯酸盐和高氯酸盐残留量

目的 建立了超高效液相色谱-串联质谱法测定食品中氯酸盐和高氯酸盐残留量的方法。方法 食品样品经纯水溶解,乙腈提取,固相萃取柱净化,超高效液相色谱-串联质谱测定。采用多反应监测模式,电喷雾电离源负离子模式,内标法定量。结果 氯酸盐在0~200 ng/mL、高氯酸盐在0~100 ng/mL范围内线性关系良好,相关系数(r)均大于0.99,检出限(S/N=3)为氯酸盐6.0μg/kg和高氯酸盐1.0 μg/kg,定量限(S/N≥10)为氯酸盐18.0μg/kg和高氯酸盐3.0 μg/kg。以不含氯酸盐和高氯酸盐的样品作为空白样品进行添加回收试验,氯酸盐的回收率为83.7%~106.9%,相对标准偏差(RSD)为2.9%~6.2%,高氯酸盐的回收率为87.8%~112.8%,相对标准偏差(RSD)为2.9%~7.5%。结论 该方法不但可以有效排除复杂基体的干扰,而且简单、灵敏、稳定。     

液相色谱-串联质谱法检测奶制品中9种 β-受体阻断剂药物残留量

目的 建立同时检测奶制品(牛奶、奶粉、奶酪)中9 种β-受体阻断剂(β-blockers, BBS)残留的液相色谱-串联质谱方法。方法 混合均匀的试样经β-葡糖醛苷酶/芳基硫酸酯酶水解, 乙腈提取, 硅藻土与BondElut分散固相萃取填料双重快速净化后, 利用液相色谱-串联质谱法进行定性定量分析。结果 9 种BBs在0.1~20.0 μg/L线性范围内线性关系良好(r≥0.995); 定量限(limit of quantity, LOQ, S/N≥10), 均达到0.5 μg/kg; 3 个添加水平(0.5、1.0和5.0 μg/kg)下的回收率为89.5%~112.5%; 相对标准偏差(relative standard deviation, RSD)为4.2%~11.5%。结论 该方法快速、准确、灵敏, 可用于奶制品样品中多种BBs残留的同时有效测定。     

气相色谱-质谱法测定植物油中壬基酚含量

目的建立气相色谱-质谱法(gas chromatography-mass spectrometry,GC-MS)检测植物油中壬基酚(4-nonylphenol,4-NP)的分析方法,了解市售植物油中壬基酚的污染状况。方法样品加入乙腈提取液,超声提取、固相萃取柱净化、七氟丁酸酐衍生化后,采用GC-MS进行检测,同位素内标法定量。结果在线性范围5~200μg/kg内,方法回归方程为Y=7.78×10~(-3)X,相关系数为0.9991。方法的检出限为3.0μg/kg,定量限9.8μg/kg。加标回收率范围为75.7%~107.4%,相对标准偏差(relative standard deviation, RSD)为5.5%~9.7%。共检测50份市售植物油样品,其中26份植物油样品检出4-NP,检出率为52%,含量范围为3.21~28.2μg/kg,中位值为3.63μg/kg。结论此方法灵敏度较高,可用于植物油中4-NP的准确定量。检测数据表明,植物油样品壬基酚检出率较高,因此对其含量的监测不容忽视。     

婴幼儿配方奶粉中邻苯二甲酸酯的固相萃取净化-气相色谱-质谱法测定

建立婴幼儿配方奶粉中邻苯二甲酸酯(PAEs)固相萃取净化,气相色谱-质谱法测定的方法。样品加入同位素内标后,以乙腈提取,PSA/Silica固相萃取柱净化,气相色谱-质谱法检测,内标法定量。结果表明:该方法对婴幼儿配方奶粉的16种PAEs定量限为50~100μg/kg,加标回收率在74%~124%之间,RSD在0.78%~7.1%之间。该方法简便快捷,定量准确,重现性好,适用于高通量检测婴幼儿配方奶粉中PAEs质量分数。     

滤过型净化-超高效液相色谱-三重四极杆/复合线性离子阱质谱法测定草鱼肌肉冻干粉中4种硝基呋喃类代谢物

目的 建立一种基于滤过型净化柱净化,结合超高效液相色谱-串联质谱法(ultra performance liquid chromatography-tandem mass spectrometry, UPLC-MS/MS)测定草鱼肌肉冻干粉中4种硝基呋喃类代谢物的快速检测方法。方法 制备阴性草鱼肌肉冻干粉作为检测目标。样品经水解、衍生化并提取浓缩后,采用以50 mg C18为净化填料的CAFS Clean-up净化柱对复溶液进行1次快速净化,超高效液相色谱分离,三重四极杆/复合线性离子阱质谱仪进行测定,内标法定量分析。结果 4种硝基呋喃类代谢物在其相应的质量浓度范围内线性关系良好(r＞0.999),定量限为0.6~2.4 μg/kg;样品中添加定量限、2.5 μg/kg、5.0 μg/kg和50.0 μg/kg浓度水平时的平均回收率在81.3%~115.1%之间,相对标准偏差为1.5%~13.1%。结论 该方法经济、简便、高效,灵敏度高,重复性好,可作为草鱼肌肉冻干粉中4种硝基呋喃类代谢物的基体标准物质的检测方法。     

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。     

凝胶渗透色谱-高效液相色谱法测定火麻仁油中Δ9-四氢大麻酚含量

目的 建立使用凝胶渗透色谱(GPC)净化,高效液相色谱(HPLC)分析测定火麻仁油中Δ⁹-四氢大麻酚(Δ⁹-THC)的检测方法。方法 样品经环已烷和乙酸乙酯溶解,经GPC净化分离,再以Agilent Eclipse XDB-C₁₈色谱柱(150 mm×4.6 mm,3 μm)分离,以乙腈-水流动相洗脱,二级管阵列检测器分析,外标法定量。结果 该方法在0～500 μg/L浓度内,线性相关系数(r)＞0.999,方法检测限(LOD)为0.05 mg/kg,定量限(LOQ)为0.17 mg/kg。加标回收率在84.6%～101.8%之间,相对标准偏差为3.2%～4.7%(n=6)。在实际样品检测中,10种不同品牌的火麻仁油中Δ⁹-THC含量在0.40～5.82 mg/kg之间。结论 该方法稳定性好,灵敏度高,适用于火麻仁油样品中Δ⁹-THC的检测分析。     

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