低温离心净化-高效液相色谱法快速测定 腐竹中的碱性橙II和碱性嫩黄O

目的 建立腐竹中碱性橙II和碱性嫩黄O的低温离心净化-高效液相色谱测定方法。方法 样品经70%的乙腈-氨水(0.5%)提取,4 ℃低温、12000 r/min离心净化,高效液相色谱(high performance liquid chromatography, HPLC)分离, 最后采用二极管阵列检测器(PDA)检测, 以保留时间(Rt)定性, 外标法定量。结果 在0.00125~0.05 mg/mL的浓度范围内, 标准曲线有良好的线性关系, 相关系数大于0.9999; 样品在0.05、2.0、10.0 mg/kg三个加标水平内的回收率范围为95.0%~103.0%(n=10), 相对标准偏差小于5.0%。方法的检出限(LOD)为0.02 mg/kg, 定量限(LOQ)为0.05 mg/kg。结论 对实际样品测试结果与参考文献方法比较, 该方法具有简便、快速、灵敏、费用低, 便于推广应用。     

高效液相色谱法同时检测食品中的碱性橙、碱性嫩黄O和碱性桃红T染料含量

建立了食品中碱性橙、碱性嫩黄O 和碱性桃红T 染料含量的高效液相色谱检测方法。样品经碱化甲醇提取,提取液在碱性条件下用二氯甲烷萃取,浓缩后用酸化甲醇溶解并用甲醇饱和正己烷萃取净化后经高效液相色谱分离、检测。本方法检测限分别为碱性橙0.02mg/kg、碱性嫩黄O 0.03mg/kg、碱性桃红T 0.004mg/kg。6 种食品样品加标回收率实验所得回收率为72.3%～96.5%,相对标准偏差(RSD)为0.3%～8.8%(n=6),三种染料在0.05～2.5μg/ml 浓度范围内均呈良好的线性关系,线性回归系数(r)均大于0.9998。     

HPLC同时测定豆制品中3种碱性橙染料

建立腐竹等固体豆制品中碱性橙2、碱性橙21和碱性橙22染料含量的高效液相色谱检测方法。样品经无水乙醇提取,超声波辅助萃取,离心合并上清液,经旋转蒸发仪浓缩至近干,定容液溶解残渣,离心吸取上清液,过0.45μm膜经高效液相色谱分离、检测。所用色谱柱为C18,检测波长碱性橙2为449 nm,碱性橙21、碱性橙22为485 nm;流动相为甲醇-乙酸铵水溶液。本方法检测限为0.02 mg/kg;定量限为0.08 mg/kg。腐竹样品加标回收率试验所得回收率为83.1%~116.7%,相对标准偏差(RSD)为1.02%~9.65%(n=6),3种染料在0.1μg/m L~20μg/m L浓度范围内均呈良好的线性关系,线性回归系数(r)均大于0.999 9。     

LC-MS/MS测定黄鱼中碱性嫩黄O及酸性橙Ⅱ

建立高效液相色谱-串联四极杆质谱正负离子切换模式同时快速测定黄鱼中黄色工业染料碱性嫩黄O及酸性橙Ⅱ的检测方法。样品匀质后,经乙腈提取,盐析,-20℃冷冻脱脂,低温离心后,取乙腈层采用高效液相色谱-串联质谱法分离、测定。结果表明碱性嫩黄O在0.5μg/kg~10μg/kg、酸性橙Ⅱ在5μg/kg~100μg/kg范围内呈良好的线性关系,高中低浓度回收率在70%~110%,相对标准偏差(n=5)小于15%,碱性嫩黄O、酸性橙Ⅱ检出限分别为0.5、5μg/kg。本方法适用于黄鱼中违禁工业染料碱性嫩黄O及酸性橙Ⅱ的测定。     

固相分散-液相色谱质谱联用法检测辣椒粉中的碱性橙和碱性玫瑰精

目的建立辣椒粉中的碱性橙和碱性玫瑰精的高效液相色谱-串联四极杆质谱测定方法。方法样品经乙腈超声提取后,经ODS-C18和乙二胺-N-丙基硅烷(PSA)的固相分散净化后直接进样分析。使用安捷伦Zobax Eclipse Plus-C18(2.1 mm×100 mm,1.8μm)色谱柱分离,以5 mmol/L乙酸铵-0.1%甲酸-乙腈为流动相,流速为0.25 mL/min。采用电喷雾离子化源,以多反应监测(MRM)方式分析,正离子化进行检测。结果碱性橙和碱性玫瑰精的线性范围为5~1000μg/L,相关系数良好。辣椒粉中碱性橙和碱性玫瑰精的检出限分别为2μg/kg和0.5μg/kg,该方法在三个水平上添加回收率为88.1%~106.4%,相对标准偏差为5.3%~11.7%。结论本方法灵敏度高,操作简单高效,适合于辣椒粉中碱性橙和碱性玫瑰精的定量及确证分析。     

固相分散净化-液相色谱质谱联用法检测辣椒粉中的碱性橙和碱性玫瑰精

目的 建立辣椒粉中的碱性橙和碱性玫瑰精的高效液相色谱-串联四极杆质谱测定方法。方法 样品经乙腈超声提取后, 经ODS-C18和乙二胺-N-丙基硅烷(PSA)的固相分散净化后直接进样分析。使用安捷伦Zobax Eclipse Plus-C18(2.1 mm×100 mm, 1.8 μm)色谱柱分离, 以5 mmol/L乙酸铵-0.1%甲酸-乙腈为流动相, 流速为0.25 mL/min。采用电喷雾离子化源, 以多反应监测(MRM)方式分析, 正离子化进行检测。结果 碱性橙和碱性玫瑰精的线性范围为5~1000 μg/L, 相关系数良好。辣椒粉中碱性橙和碱性玫瑰精的检出限分别为2 μg/kg和0.5 μg/kg, 该方法在三个水平上添加回收率为88.1%~106.4%, 相对标准偏差为5.3%~11.7%。结论 本方法灵敏度高, 操作简单高效, 适合于辣椒粉中碱性橙和碱性玫瑰精的定量及确证分析。     

Oasis PRiME HLB-高效液相色谱-串联质谱法测定黄鱼中的碱性嫩黄O

目的 建立Oasis PRiME HLB-高效液相色谱-串联质谱法测定黄鱼中的碱性嫩黄O的分析方法。方法 样品经乙醇提取液充分提取, 经涡旋、超声、低温高速离心后, 上清液过Oasis PRiME HLB固相萃取柱净化, 流出液经氮吹吹干, 复溶, 待质谱分析。结果 在1.5、15.0、30 μg/L 3个加标浓度下, 回收率为85.3%~ 94.8%, 相对标准偏差为3.0%~7.2%, 方法定量限为1 μg/kg。结论 该方法前处理十分简便, 固相萃取净化水平高, 色谱串联质谱分析快速灵敏, 回收率高, 灵敏度高, 适合黄鱼中非食用物质碱性嫩黄O的定性定量 分析。     

高效液相色谱法测定食品中非食用色素

建立食品中的酸性橙Ⅱ、碱性橙2和碱性嫩黄O染料残留的高效液相色谱同时测定的方法,样品通过提取之后,采用基质固相分散法净化,然后分别用乙醇和乙醇-氨水-水(7:2:1)分步洗脱,最后进行HPLC分离、检测.此方法的回收率平均为79%.酸性橙Ⅱ的检出限为0.01 mg/kg、碱性橙2的检出限为0.02 mg/kg,碱性嫩黄O染料的检出限为0.01 mg/kg,相对标准偏差平均为3.53%.     

超声波萃取-高效液相色谱法测定纺织品中碱性嫩黄

建立了超声波萃取-高效液相色谱法测定纺织品中碱性嫩黄含量的分析方法。以甲醇作为溶剂,样品中的目标分析物经超声萃取后,采用高效液相色谱进行测定。结果表明：碱性嫩黄在质量浓度为0.1～5.0μg/mL范围内具有良好的线性关系,线性相关系数大于等于0.998,方法检出限为2.0 mg/kg。加标回收率、准确度和精密度实验结果表明,加标回收率在90.7%～95.5%,说明本方法重现性良好。     

液相色谱-串联质谱法检测调味品中碱性橙2的残留量

目的建立液相色谱-电喷雾质谱法(liquid chromatography-tandem mass spectrometry, UPLC–MS/MS)检测调味品中碱性橙2的分析方法。方法样品经酸化乙腈提取,正己烷去脂后,经固相萃取小柱净化,氮气吹干进行富集后,用乙腈溶解,再采用液相色谱-电喷雾质谱进行检测,以正离子多反应监测模式测定,外标法定量。结果碱性橙2的线性范围为0.2～20 ng/mL,线性方程为Y=0.0993X-0.0106 (r=0.9999),加标回收率为90.0%～110.0%,相对标准偏差小于10.0%(n=6);方法检出限为1μg/kg,定量限为3μg/kg。结论该方法快速、准确、灵敏,适合用于食品中碱性橙2的确证检测。     

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