SPE-HPLC法测定啤酒中的微量反-2-壬烯醛

采用固相萃取-高效液相色谱法对啤酒中的微量反-2-壬烯醛进行检测.啤酒样品经水蒸汽蒸馏、Supelclean LC-18固相萃取小柱净化后,采用Nucleosil 100-5 C18色谱柱(250mm×4.0mm,5μm)分离,流动相乙腈:水=55:45(V/V),流速为lmL/min,检测波长226nm.在10～150μg/L范围内,峰面积与反-2-壬烯醛浓度呈良好的线性关系(r=0.9998),精密度(RSD)小于5%,样品浓缩250倍后检测限为0.25μg/L,平均回收率在80.4%～109.8%之间.     

GPC-HPLC-FLD 法测定动植物油脂中的苯并(a)芘

建立动植物油脂中苯并(a)芘残留量的凝胶净化-高效液相色谱-荧光检测的测定方法。方法采用凝胶色谱净化系统处理样品,可除去油脂中甘油三酯等杂质的干扰。色谱条件：Hypersil ODS2(150mm×4.6mm,5μm)反相色谱柱,流动相为甲醇-水(94:6,V/V),流速1.0mL/min,激发波长365nm,发射波长406nm,柱温30℃。方法的检出限0.1μg/kg,线性范围0.1～50μg/kg,加标回收率92.0%～106.0%,相对标准偏差为1.86%(n＝6)。该法具有样品预处理简单、灵敏度高、精密度高等优点,可用于动植物油脂样品中苯并(a)芘的快速准确测定。     

高效液相色谱法测定鸡蛋中三聚氰胺

建立采用固相萃取净化,高效液相色谱法测定鸡蛋中三聚氰胺含量的方法。样品采用三氯乙酸和乙酸铅溶液提取,优化样品提取时间、色谱柱及固相萃取柱,最终确定为样品提取20min、采用TC-C18(4.6mm×150mm,5μm)色谱柱和PCX固相萃取柱。采用紫外检测器,检测波长为240nm,流动相为乙腈:辛烷磺酸钠-柠檬酸缓冲液(10:90,V/V),流速1.0mL/min,进样量20μL,外标法定量。三聚氰胺在1～50μg/mL范围内,具有良好的线性关系(R2=1),在添加质量浓度为5～20mg/kg范围内,三聚氰胺添加回收率在72.8%～87.6%,RSD(n=6)为1.5%～4.0%,最低检测限为0.54mg/kg。     

亲水作用色谱柱-高效液相色谱法测定鸡蛋中氨丙啉的残留量

目的建立亲水作用色谱柱-高效液相色谱法检测鸡蛋中氨丙啉残留的分析方法。方法样品加入10 mL5%三氯乙酸水溶液进行提取,离心后取一半上清液过HLB柱净化。色谱柱为Poroshell 120 HILIC-Z (100 mm×3.0 mm, 2.7μm),流动相为5 mmol/L乙酸铵-0.1%甲酸水溶液和乙腈,等度洗脱, 5 mmol/L乙酸铵-0.1%甲酸水溶液:乙腈=20:80(V:V),流速为0.4 mL/min,进样量为20μL,检测波长267 nm。结果氨丙啉在0.35～10.0μg/mL呈良好的线性关系, r大于0.999。方法的最低定量限为250μg/kg。氨丙啉在250～2000μg/kg的浓度添加水平上,其回收率在85.0%～96.7%,批内、批间的相对标准偏差小于6%。结论该方法具有简便快捷、灵敏度高等特点,适用于鸡蛋中氨丙啉的残留检测。     

超高效液相色谱法测定清咽含片中罗汉果皂苷V

目的建立超高效液相色谱法(ultra performance liquid chromatography,UPLC)测定清咽含片中罗汉果皂苷V含量的方法。方法色谱条件为色谱柱:XSELECT HSS T_3(100 mm×2.1 mm,2.5μm);流动相:乙腈:0.1%磷酸水溶液,梯度洗脱,流速:0.4 mL/min;柱温:40℃;进样量:5μL;检测波长:203 nm。结果结果表明,罗汉果皂苷V线性范围为0.033~0.333 mg/mL(r=1.0000),检出限66.4μg/g,定量限221.6μg/g,精密度(relative standard deviation,RSD)为1.5%,平均回收率97.6%(n=9)。结论此法操作简单、准确、快速,可作为清咽含片中罗汉果皂苷V含量的检测方法。     

钛胶正相高效液相色谱法同时分析三聚氰胺和三聚氰酸

建立了同时分析液态奶、自来水和游泳池水中三聚氰胺和三聚氰酸的钛胶正相高效液相色谱法。色谱条件:分离柱为Titania Sachtopore-NP柱(250mm×4.6mm×5μm),流动相为水∶甲醇=50∶50(V/V)、流动相中含醋酸盐1.0mmol/L、pH7.0、流速0.8mL/min、柱温60℃、UV检测波长210nm。三聚氰胺和三聚氰酸分别在0.1～10μg/mL和2～100μg/mL范围内与对应的峰面积呈良好的线性关系,检出限分别为0.02μg/mL和0.1μg/mL,本方法三聚氰胺的回收率为94.8%～111.7%,三聚氰酸回收率为103.9%～114.3%,三聚氰胺和三聚氰酸测定结果的相对标准偏差分别为0.62%和0.78%(n=8)。     

高效液相色谱法检测保健食品中的番茄红素

目的建立高效液相色谱法测定保健食品中番茄红素的分析方法。方法用含有0.1%2,6-二叔丁基-4-甲基苯酚抗氧化剂的甲醇:二氯甲烷(10:90,V:V)作为提取溶液。通过Agilent Eclipse XDB-C_(18)(4.6 mm×250mm,5μm)色谱柱;甲醇:乙酸乙酯(85:15,V:V)作为流动相,二极管阵列检测器,检出波长475 nm,色谱柱温25℃,流速1.0 mL/min,进样体积10μL,作为检测条件。结果番茄红素在0~200μg/mL范围内线性良好,相关系数r=0.9995,最低检出限为0.0815μg/mL,平均回收率在89.7%~109.8%之间,RSD为8.4%。结论本方法可以准确、快速地检测保健食品中的番茄红素。     

高效液相色谱法测定牛奶中林可霉素的残留量

研究建立牛奶中林可霉素残留量的高效液相色谱测定方法。样品用水相提取,离心分离,经C18固相萃取柱净化,在210nm波长下用二极管矩阵检测器检测。色谱柱为Agilent ZORBOX SBC18柱(4.6×250mm,5μm),以0.05mol/L硼砂溶液(用磷酸调节pH6.0)-甲醇(55:45,V/V)为流动相,流速1.0ml/min。林可霉素浓度在1.0～10.0μg/g范围内与峰面积呈良好的线性关系,平均回收率为82.9%～93.1%,变异系数为1.45%～4.58%,最低检测限为0.5μg/ml。本方法简便、快速、准确。     

免疫亲和柱净化-液相色谱-串联质谱法同时测定水产品中8种霉菌毒素

目的:建立免疫亲和柱净化-液相色谱-串联质谱法(LC-MS/MS)同时测定水产品中8种霉菌毒素残留。方法:样品经乙腈水溶液(84:16,V:V)提取,多毒素免疫亲和柱净化。色谱柱为Agilent Proshell 120 SB·C₁₈(2.1 mm×100 mm,2.7μm),流动相为甲醇-5 mmol/L乙酸铵(含0.1%甲酸),梯度洗脱,流速为0.4 mL/min,柱温为40℃。采用电喷雾离子源正负离子同时扫描,多反应监测模式(MRM)进行质谱检测。结果:8种霉菌毒素在1.0～50.0 ng/mL范围内线性关系良好(R²>0.992),方法检出限在0.05～0.50μg/kg之间,定量限在0.17～1.65μg/kg之间;8种霉菌毒素加标回收率在75.6%～106.3%之间,相对标准偏差(RSD)为3.5%～9.3%。结论:该方法操作便捷、灵敏度高、准确可靠,能满足水产品中多种霉菌毒素残留快速检测需求。     

高效液相色谱法同时测定面制品中顺丁烯二酸和富马酸的含量

目的建立用高效液相色谱法同时测定面制品中的顺丁烯二酸和富马酸含量。方法样品经50 ml 10%甲醇-水萃取,离心后,水层过0.45μm滤膜,经Waters Atlantis T3色谱柱(250 mm×4.6 mm,5μm)分离,以0.1%磷酸-甲醇(95∶5,V/V)作流动相,紫外检测器检测,波长210 nm。结果在优化的试验条件下,顺丁烯二酸和富马酸的浓度在0.1~25μg/ml范围内与峰面积呈良好的线性关系,回归方程分别为y_(顺丁烯二酸)=147008x-1316.8(r=0.999 5,n=6)和y_(富马酸)=176689x-670.1(r=0.999 6,n=6),方法检出限均为2.0 mg/kg,回收率为86.88%~93.02%,相对标准偏差为0.67%~1.08%。结论该方法简便、准确,可适用于面制品中顺丁烯二酸和富马酸的同时测定。     

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