实时荧光定量PCR技术检测转基因大豆方法的建立

采用实时荧光定量PCR技术 ,通过使用特异的引物和探针 ,对大豆中的内源基因Lectin和转基因大豆中的外源基因EPSPS进行了定量检测 ,建立了Monsanto公司生产的商业化转基因大豆Roundup Ready○R的定量PCR检测方法。该方法的检测灵敏度 <0 0 1% ,是国际上设定的转基因最低限量的 10 0倍     

婴幼儿配方奶粉中氯酸盐和高氯酸盐污染情况的调查分析

对婴配奶粉中氯酸盐和高氯酸盐的污染情况进行调查分析,采用超高效液相色谱-串联质谱(UPLC-MS-MS)法,同位素内标法定量测定,对测定结果进行分析。结果显示,婴配奶粉中氯酸盐的检出率为49.8%,高氯酸盐的检出率为34.4%,氯酸盐的检出率高于高氯酸盐。不同段数婴配奶粉氯酸盐和高氯酸盐的平均暴露量随着段数的增加呈下降趋势。1、2段婴配奶粉氯酸盐超过限量占比均超过10%,3段婴配奶粉氯酸盐超过限量占比在10%以下。不同段数婴配奶粉高氯酸盐超过限量占比均在10%以下。婴配羊奶粉中氯酸盐超过限量占比高达22.1%,高氯酸盐超过限量占比高达23.2%。对0～12月龄的婴儿,氯酸盐摄入的健康风险需引起重点关注。高氯酸盐污染风险相对较低,但是婴配羊奶粉氯酸盐和高氯酸盐污染较为严重。     

信宜三华李农药残留膳食摄入风险评估

了解信宜三华李农药残留量的状况,并开展农药残留膳食摄入风险评估,为农药残留监管和农药最大残留限量提供科学依据。从信宜市采集66批次三华李样品,检测70种农药残留量,对检出残留的农药进行急性膳食摄入风险和慢性膳食摄入风险评估;用急性风险的消费者保护水平和慢性风险的消费者保护水平对农药最大残留限量进行评估。样品的合格率为98.5%,农药残留检出率为48.5%,农药种类检出率为11.4%,超农药最大残留限量率为1.5%。急性膳食摄入风险、慢性膳食摄入风险、急性风险的消费者保护水平和慢性风险的范围依次是0～0.22%,0.06%～14.58%, 20.3～169.0倍和3.9～154.3倍。三华李农药残留膳食摄入风险较低,现行有效的农药最大残留限量对消费者保护水平是安全的。     

大米中敌稗残留量测定方法的研究

为贯彻实施敌稗农药最大残留限量国家标准 ,建立大米中敌稗残留量测定方法 ,试样用丙酮提取 ,石油醚萃取和弗罗里硅土净化 ,乙醚 -正己烷 (1∶1)淋洗。净化液用配有电子捕获检测器的气相色谱仪测定 ,外标法定量。方法最低检测浓度 4× 10 -4mg kg ,敌稗浓度在 0 2 0～ 2 0 0mg kg范围内 ,平均回收率为 89 7%～ 90 7% ,相对标准偏差为 4 4 6 %～ 5 2 1% ,符合农药残留分析的要求。     

量子点微球免疫层析试纸条检测鸡蛋中恩诺沙星的性能评价

目的:现场快速筛查鸡蛋中恩诺沙星。方法:按《食品安全国家标准食品中41种兽药最大残留限量》要求，依据国家市场监督管理总局2023年1月发布的《关于规范食品快速检测使用的意见》,制备3个浓度水平的恩诺沙星加标样本。50份空白样本和50份标准限量要求0.5倍浓度水平(5μg/kg)的加标样本用以评价快检方法的假阳性率；50份标准限量要求1倍浓度水平(10μg/kg)的加标样本用以评价快检方法的假阴性率。50份实际鸡蛋样本用量子点微球免疫层析试纸条与HPLC-MS/MS方法分别进行检测。结果:量子点微球免疫层析试纸条可以满足国家限量要求，假阴性率为0%,假阳性率为0%。实际样本检测时，量子点微球免疫层析试纸条与HPLC-MS/MS方法的结果符合率高。结论:借助于便携式读取仪，量子点微球免疫层析法可获得数字化的准确结果，适合鸡蛋中风险因子的大批量样本现场快速筛查。     

气相色谱法测定食品中三氯杀螨醇残留量的研究

为实施食品中三氯杀螨醇限量卫生标准 ,建立了毛细管气相色谱法测定食品中三氯杀螨醇残留量的方法 ,试样以石油醚提取 ,浓硫酸净化 ,用DB - 1型毛细管柱分离测定。测定条件 :柱温 2 4 0℃ ;检测器 (ECD)温度 30 0℃ ;进样口温度 2 80℃ ;载气 (N2 )流量 5 0mL min ;压力 15 0kPa ;分流比 5 0∶1。该方法前处理简单 ,分离效果与重现性好 ,回收率为 91%～ 99 5 % ,相对偏差为 4 0 %～9 3% ,线性范围为 0 0～ 1 0 μg mL ,最低检测限为 8 0× 10 -3 ng。该方法可以满足检测食品中三氯杀螨醇残留的需要。     

超声辅助顶空固相微萃取气相色谱法测定皮革中芳香烃残留

试样剪碎后置于饱和NaCl溶液中40℃超声处理后,采用100μm聚二甲基硅氧烷(PDMS)作为固相微萃取技术(SPME)装置的固相涂层,采用顶空固相微萃取气相色谱(HS-SPME-GC-MS)法,测定了皮革样品中部分芳香烃(苯、甲苯、乙苯、对-二甲苯和异丙苯)残留。方法给出了相应的检测限量和适用范围,目标化合物的检测限量低于0·001mg/kg,回收率在96·8%~103·7%之间。     

气相色谱法测定大米中稻瘟灵残留量

稻瘟灵 (Ｉｓｏｐｒｏｔｈｉｏｌａｎｅ)是一种内吸低毒杀菌剂农药。我国已批准大米中的残留限量为 1 0ｍｇ ｋｇ ,然而 ,尚无统一的标准分析方法与之配套使用。为此 ,我站接受了中国预防医学科学院标准处的委托 ,研制了本检测方法。本法操作简便、准确、线性关系良好 ,相对标准偏差小于 10 % ,平均回收率为10 8 4 % ,最低检出量为 0 2 6ｎｇ ,若取大米试样 2 0 0ｇ ,则最低检出浓度为 0 0 13ｍｇ ｋｇ ,能满足稻瘟灵农药残留分析的要求。1　材料与方法1 1　仪器与设备日本岛津ＧＣ 14Ａ型气相色谱仪 ,配火焰光度检测器 (ＦＰＤ) ;电动振…     

液相色谱-串联质谱法检测食用油脂中多环芳烃

建立了有机溶剂萃取、硅胶固相萃取柱净化、液相色谱-串联质谱法(LC-MS/MS法)测定食用油脂中EPA 16种多环芳烃的检测方法。EPA 16种多环芳烃的定量限分别为0.02~0.43μg/kg,回收率为86.5%~104.6%,日内精密度小于6%,日间精密度小于5%。在40个受测油脂样品中,EPA 16种多环芳烃的含量范围为11.68~146.06μg/kg。对照我国GB 2716规定,所有受测样品中苯并(a)芘含量均不超过≤10μg/kg的限量标准。然而,8个油样的苯并(a)芘含量超过了欧盟≤2μg/kg的限量标准,10个油样的PAH4含量超过了欧盟≤10μg/kg的限量标准。     

出口调味粉中大肠菌群的检测及其污染分析

通过对某注册出口食品企业进行为期8个月的出口调味粉样品进行大肠菌群检测,样品包含6个品种共计301份,结果共检测到大肠菌群超过限量值150 MPN/100 g共有15份:SA调味粉131份,超过限量值有6份,占该品种4.6%;SB调味粉133份,超过限量值有3份,占该品种2.3%;SC调味粉8份,超过限量值有2份,占该品种25%;SD调味粉14份,超过限量值有2份,占该品种14.3%;SE调味粉6份,超过限量值有1份,占该品种16.7%;SF调味粉9份,超过限量值有1份,占该品种11.1%.然后分析了它们被污染的可能原因,从而找出相应控制措施,为出口企业提高产品品质、生产优质复合调味粉提供参考依据,从而确保出口调味粉的质量安全.     

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