气相色谱-三重四极杆串联质谱法测定肉制品中7种己二酸酯类物质残留

目的 建立气相色谱-三重四极杆串联质谱法同时测定7种己二酸酯类物质残留量的分析方法,并对肉制品中7种己二酸酯类物质进行筛查。方法 样品经乙腈提取,提取液用Sin Ch ERS-General柱净化,多反应监测模式进行检测,基质匹配曲线外标法定量。结果 采用基质匹配标准曲线定量的方法降低了基质效应,满足定量分析要求。该方法线性关系良好, 7种己二酸酯类物质的线性范围为0.01～0.40 mg/L,相关系数(r2)均大于0.999。在0.04、0.10、0.20mg/kg3个不同加标浓度水平下,7种己二酸酯类物质的回收率为73.5%～117.5%,相对标准偏差(relative standard deviations, RSDs)为0.8%～8.2%。方法检出限为0.01 mg/kg,方法定量限为0.03 mg/kg。对59份肉制品中的7种己二酸酯类物质含量进行检测分析,结果显示,有6份样品检出,其中己二酸二(2-乙基己基)酯的检出浓度为0.071～5.930 mg/kg,双(1-丁基戊基)己二酸酯的检出浓度为0.056～0.480 mg/kg,其他己二酸酯类物质均未检出。结论 该方法前处...     

超高效液相色谱-三重四极杆质谱法快速测定煎炸过程用油中的苯并[a]芘

建立快速检测煎炸过程用油中苯并[a]芘的超高效液相色谱-三重四极杆质谱联用(UPLC-MS/MS)分析方法。样品用乙腈提取后,经EMR-Lipid脂质增强型固相萃取柱净化,以乙腈和水作为流动相进行梯度洗脱,在RRHD SB-C₁₈柱上实现分离,大气压化学电离(APCI)-三重四极杆质谱正离子多反应监测(MRM+)方式检测,以苯并[a]芘-d₁₂作为内标的稳定同位素稀释法定量。结果表明,方法的线性范围为1~200 μg/kg,决定系数R2=0.9997,检出限为0.2 μg/kg,定量限为0.6 μg/kg。平均加标回收率为94.0%~98.7%,相对标准偏差为2.1%~5.6%。20批样品中均检出苯并[a]芘,含量在1.76~6.81 μg/kg之间。该方法前处理简单、基质干扰少、定性定量准确、灵敏度高,适用于煎炸过程用油中苯并[a]芘的测定。     

固相萃取-气相色谱-串联质谱法测定木耳中五氯苯酚

目的 研究建立木耳中五氯苯酚的固相萃取-气相色谱串联三重四极杆质谱（Gas chromatography-tandem triple quadrupole mass spectrometry,GC-MS/MS）测定方法。方法 以2,4,6-三溴苯酚为内标物,样品经5%三氯乙酸（Trichloroacetic acid,TCA）浸提,以乙酸乙酯/正己烷液-液分配法萃取五氯苯酚,经SLC（氧化铝/SCX）固相萃取柱净化样品提取液,乙酸酐衍生,HP-5MS 30m×0.25mm×0.25μm毛细管柱分离样品,GC-MS/MS多反应监测（Multiple Reaction Monitoring, MRM）测定,内标法定量。结果 建立的五氯苯酚方法浓度在1~100 ng/mL范围具有良好线性关系,线性相关系数（γ）:>0.9999,在方法线性范围内低、中、高三个浓度水平加标回收率在89.3%~108.7%之间,相对标准偏差2.1%~9.0%。方法检出限为0.06μg/kg,定量限为0.2μg/kg。结论 建立的五氯苯酚测定方法灵敏度高,方法稳定,重现性好,可用于木耳样品中五氯苯酚的定性定量测定。     

气相色谱-质谱法测定黑木耳中草甘膦和氨甲基膦酸残留量

目的 采用气相色谱-质谱法建立一种黑木耳中草甘膦和氨甲基膦酸残留的分析方法。方法 干制黑木耳样品经二氯甲烷脱色、水提取、盐酸沉淀蛋白、乙醇沉淀多糖后, 与三氟乙酸酐和七氟丁醇进行衍生化反应, 经气相色谱柱分离后, 在选择离子监测（selected ions monitoring, SIM）模式下进行草甘膦和氨甲基膦酸含量的测定, 外标法定量。结果 干制黑木耳中草甘膦在0.001~0.050 μg/mL浓度范围内呈现良好线性(相关系数R2=0.9993), 表现为弱基质抑制效应, 检出限为0.02 mg/kg, 定量限为0.04 mg/kg, 在0.04、0.08、0.20 mg/kg 3个添加水平下, 平均回收率为82.4%~93.4%, 相对标准偏差为7.8%~9.5%(n=6); 氨甲基膦酸在0.0005~0.050 μg/mL浓度范围内呈现良好线性(相关系数R2=0.9996), 表现为弱基质增强效应, 检出限为0.01 mg/kg, 定量限为0.02 mg/kg, 在0.02、0.08、0.20 mg/kg 3个添加水平下, 平均回收率为85.6%~96.8%, 相对标准偏差为5.7%~9.3%(n=6)。结论 该方法针对干制黑木耳基质, 样品前处理过程简单, 净化除杂效果好且回收率高, 满足农药残留分析实验室对黑木耳中草甘膦和氨甲基膦酸残留的检测要求。     

气相色谱-质谱法测定食品用纸制品中五氯酚含量

目的建立气相色谱-质谱法测定食品用纸制品中五氯酚含量的分析方法,了解食品用纸制品中五氯酚的残留状况。方法纸制品试样加入2,4,6-三溴酚内标后,经液-液萃取, SLC柱净化,乙酸酐-吡啶溶液衍生后,采用气相色谱-质谱法测定,内标法定量。结果在50~1000ng范围内,相关系数均>0.9995。方法的检出限为0.008mg/kg,定量限为0.025mg/kg。加标回收率为89.3%~109.8%,相对标准偏差(relativestandard deviations, RSDs)分别为3.2%、8.6%和4.4%。106份市售纸制品中, 8份样品检出五氯酚,阳性率为7.5%,含量范围为0.011~0.045 mg/kg,阳性样品五氯酚含量的平均值为0.027 mg/kg。结论该方法灵敏度较高,精密度好,适用于纸制品中五氯酚的准确定量检测。检测数据表明,食品用纸制品中五氯酚风险较小。     

气相色谱-质谱法测定食用油中3-氯丙醇酯

采用碱水解方式,基于苯基硼酸 (PBA)衍生化方法并结合气相色谱/质谱 (GC/MS) 联用仪测定了植物油中3-氯丙醇 (3-MCPD) 酯的含量。水解时间是碱水解样品前处理方法的关键因素,经优化,大豆油等不同品类的食用油的最佳水解时间为 1-6 min。另外,以大豆油为基质,考察了基于碱水解方式的分离分析方法的回收率、重复性以及检出限。其中,在 150~1500 μg/kg范围内进行3水平重复加标回收实验,回收率为 94%~105%、RSD为3.7%~10.8%、检出限为 15 μg/kg,定量限为 50 μg/kg。本方法能够满足日常样品中3-氯丙醇 (3-MCPD) 酯的检测。     

超高效液相色谱-串联质谱法检测食品中腰果过敏原

基于超高效液相色谱-串联质谱系统建立食品中腰果过敏原的定量检测方法。腰果经提取、胰蛋白酶酶解、净化后,经Easy-nLC 1000纳升液相色谱分离,随后进入四极杆-静电场轨道离子阱高分辨质谱以全扫描模式进行数据采集,使用ProteinPilot软件结合Uniprot蛋白数据库对样品扫描结果进行分析,并基于基本局部比对搜索工具(BLAST)验证肽段特异性,最终筛选出6条腰果特异性肽段,利用超高效液相色谱-三重四极杆质谱系统的多反应监测模式对实际样品进行检测。结果表明,该方法在0.005～10 mg/mL范围内线性关系良好,R²均大于0.99,固体基质中定量限为2.5～5 mg/kg,饮料基质中定量限为0.005～0.01 mg/mL,平均回收率在82.5%～109.9%之间,相对标准偏差不大于8.9%。该方法灵敏度高、特异性好,可用于饼干、面包、蛋糕、桃酥、巧克力和饮料6种食品基质中的腰果过敏原检测。     

超高效液相色谱-三重四极杆质谱法测定饮料中的γ-羟基丁酸和γ-丁内酯

目的建立超高效液相色谱-三重四极杆质谱法(ultra performance liquid chromatography-tandem mass spectrometry,UPLC-MS/MS)检测饮料中γ-羟基丁酸(4-hydroxybutanoic acid,GHB)和γ-丁内酯(gamma-butyrolactone,GBL)的含量。方法样品经稀释后,采用C18色谱柱(100 mm×2.1 mm,1.7μm)进行分离,用甲醇和0.02%甲酸水作为流动相进行梯度洗脱后上机检测。结果在50~1000μg/L内GHB和GBL的浓度与峰面积的线性关系良好,相关系数均大于0.998。γ-羟基丁酸在饮料中的检出限为0.045 mg/kg,定量限为0.15 mg/kg,γ-丁内酯在饮料中的检出限为0.033 mg/kg,定量限为0.11 mg/kg。该方法在检测4种不同类型的饮料时,加标回收率为70%~130%,相对标准偏差(relative standard deviation,RSD)均小于5.0%(n=6)。结论该方法操作简单,灵敏度高,准确可靠,适用于饮料中γ-羟基丁酸和γ-丁内酯的测定。     

超高效液相色谱-串联质谱法测定食品包装材料中双酚S含量

目的 建立一种食品包装材料中双酚S含量的检测方法。方法 通过考察不同的提取方式、提取溶剂和提取温度,最后采用甲醇对食品包装材料进行超声提取,并将提取液过滤膜后直接进行超高效液相色谱-串联三重四极杆质谱分析;通过优化色谱-质谱仪器参数,最终采用多反应模式(MRM)进行定量检测。结果该方法检出限为0.10 mg/kg,定量限为0.30 mg/kg,在0.50~20 mg/kg范围内线性良好(相关系数为0.9993)。通过对空白样品进行双酚S的加标回收实验,结果表明平均回收率为89.6%~95.1%,相对标准偏差为3.1%~7.9%。结论 该方法灵敏度高、抗干扰性强、重现性好,可用于常见食品包装材料中双酚S的含量检测。     

气相色谱-质谱法测定食用油中3-氯丙醇酯

采用碱水解方式,基于苯基硼酸(PBA)衍生化方法并结合气相色谱-质谱(GC-MS)联用仪测定了食用油中3-氯丙醇(3-MCPD)酯的含量。经试验可知,水解时间是碱水解样品前处理方法的关键因素,经优化,大豆油等不同品类的食用油的最佳水解时间为1~6 min。另外,以大豆油为基质,考察了基于碱水解方式的分离分析方法的回收率、重复性以及检出限。其中,在150~1 500μg/kg范围内进行3水平加标回收试验,回收率为94%~105%、RSD为3.7%~10.8%、检出限为15μg/kg,定量限为50μg/kg。本方法能够满足日常样品中3-氯丙醇(3-MCPD)酯的检测。     

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