液相包谱法分析卷烟主流烟气中的挥发醛

为了快速准确地分析卷烟主流烟气中的低级醛酮类化合物,建立了通过装有2,4-二硝基苯肼(DNPH)衍生化试剂酸性溶液的装置捕集烟气,以吡啶为稳定剂,采用配有二极管阵列检测器的高效液相色谱仪测定卷烟主流烟气中的挥发性醛酮类化合物的方法.该方法的CV＜5%,回收率＞95%,并用外标法定量测定了7种牌号卷烟主流烟气中的5种醛酮类化合物.该方法操作简便、快速、重复性好、回收率高,适用于卷烟烟气中的醛类化合物的分析.     

GC-MS/MS法分析不同规格卷烟主流烟气醛酮类成分释放量

为考察细支、中支和常规卷烟主流烟气中醛酮类成分的释放特征,建立了同时测定卷烟主流烟气95种醛酮类香味成分的气相色谱-串联质谱(GC-MS/MS)法,采用相同烟丝配方卷制细支、中支和常规规格卷烟,检测主流烟气8种低分子量醛酮类刺激性成分和95种醛酮类香味成分.通过单因素方差分析(ANOVA)筛选出差异化合物.结果表明:①...     

化学发光法测定卷烟主流烟气中的氮氧化物

探讨了一种用化学发光法测定卷烟主流烟气中NOx 的方法 ,即将每口新鲜主流烟气经剑桥滤片过滤后引入到一个减压的混合室 ,经充分混合后 ,用氮氧化物分析仪根据化学发光原理测定卷烟主流烟气中氮氧化物。该方法的CV <5 % ,回收率 >98% ,并用外标法定量测定了 6种牌号卷烟主流烟气中的氮氧化物。该方法快速、重复性好、回收率高 ,适用于卷烟烟气中的氮氧化物的分析     

卷烟侧流烟气中有害醛酮类化合物的分析

为了测定卷烟侧流烟气中的有害醛酮类化合物,考察了卷烟侧流烟气捕集装置各部分对8种有害醛酮的捕集量和样品处理方法对其测定量的影响,建立了捕集、处理及高效液相色谱法检测卷烟侧流烟气中8种有害醛酮类的方法,并采用该方法测定了市售国内外21种卷烟样品侧流烟气中这8种有害醛酮的释放量。结果表明:所测卷烟样品侧流烟气中8种醛酮的总释放量在3300～4600μg/支之间。其中,乙醛释放量最高,在1600～2300μg/支之间;丙酮和甲醛次之,释放量在400～800μg/支之间;而其他5种醛酮的释放量在70～250μg/支之间。     

卷烟主流烟气中挥发性醛酮的LC-MS/MS分析

采用2,4-二硝基苯肼衍生-LC-MS/MS法测定了32种卷烟样品主流烟气中的甲醛、乙醛、丙烯醛、丙酮、丙醛、巴豆醛、甲基丙烯醛、2-丁酮、丁醛、苯甲醛、戊醛、己醛.结果表明:①方法的检测限为0.1～0.5 ng/mL,回收率在91.6%～100.3%之间,相对标准偏差为3.28%～7.86%;②卷烟样品主流烟气的挥发性醛酮成分中主要为乙醛和丙酮,苯甲醛、已醛含量较小;③与进口烟相比,国产烤烟型卷烟主流烟气中的挥发性醛酮含量相对较高,混合型卷烟的相对较低;④不管是烤烟型还是混合型,焦油量高的卷烟主流烟气中的挥发性醛酮含量均相对较高.     

高分辨GC-QTOF MS法分析烟草中的醛酮类香味成分

基于气相色谱-四极杆飞行时间质谱(GC-QTOF MS),针对烟草及烟用添加剂中127种重要的醛酮类香味成分,建立了包含一级高分辨质谱图、保留指数和精确相对分子质量的数据库。优化了GC-QTOF MS分析条件,建立了127种化合物的准确定量分析方法,并对构建的方法进行系统表征。采用该方法分析了国内15个不同品牌卷烟样品。结果表明:(1)GC-QTOF MS采集的数据的精确质量误差均小于2 mDa,与传统GC-MS相比,采用数据库进行定性分析的结果更准确。(2)质量提取窗口为5 mDa时,可去除干扰离子,提高灵敏度。(3)127种醛酮类化合物标准曲线线性关系良好(r~20.99);其中95种化合物的定量限(LOQs)在6～100μg/kg之间;3个添加水平下,平均回收率在61.8%～132.6%之间;115种化合物日间精密度(n=6)小于10%。(4)该方法适合各类卷烟烟丝样品中醛酮类香味成分的分析,在15个品牌卷烟样品中共检测到63种醛酮类香味成分,包括22种醛和41种酮。     

超声萃取-快速HPLC法测定卷烟主流烟气中的苯酚、甲酚和苯二酚

建立了超声萃取-快速高效液相色谱同时测定卷烟主流烟气中的苯酚、甲酚和苯二酚的方法。即用1%的醋酸水溶液于室温下对捕集了烟气粒相物的剑桥滤片超声萃取20min,将萃取液用0.45μm滤膜过滤后,滤液直接用配置荧光检测器的快速分离柱-高效液相色谱进行分析。并应用该法测定了10种国产烤烟型和10种混合型卷烟主流烟气中的挥发酚,结果表明:①该法的相对标准偏差为1.92%～4.62%,回收率97.9%～100.3%,检测限5.74～14.70ng/支,分析时间6min;②烤烟型卷烟主流烟气中苯二酚、苯酚的含量明显高于混合型卷烟,而甲酚的含量整体上略高于混合型;③同类型卷烟主流烟气中挥发酚含量高低的次序为p-苯二酚>o-苯二酚>苯酚>(m、o)-甲酚>p-甲酚>m-苯二酚。该法适合批量卷烟主流烟气中苯酚、甲酚和苯二酚的快速分析。     

一些醛酮类香料在卷烟烟丝和滤嘴中的转移行为

采用烟丝注射和滤棒添加方式进行了12种醛酮类香料单体的卷烟加香试验,并采用同时蒸馏萃取以及气相色谱和气相色谱/质谱联用等方法分别测定了这些醛酮类香料单体在烟丝和滤棒中的持留率、迁移率,及其向主流烟气中的转移率.结果显示:①烟丝加香醛酮类香料在烟丝中的持留率均低于嘴棒加香在滤嘴中的持留率,烟丝加香醛酮类香料向滤嘴中的迁移率均高于滤棒加香向烟丝中的迁移率;②滤棒加香更有利于低沸点醛酮类香料向主流烟气粒相中的转移;③互为同分异构体的苯乙醛和苯乙酮,辛醛和2-辛酮,2-庚酮、庚醛和2,5-己二酮都遵守沸点越高烟气转移率越高的规律;④滤棒加香有利于低沸点醛酮类同系物香料烟气转移率的提高.     

光电离质谱法测定卷烟烟气中有害成分的口腔残留

为了在线研究卷烟烟气中有害化学成分在人体口腔中的残留,建立了一种基于真空紫外光电离飞行时间质谱的测量装置,获得了新鲜卷烟主流烟气气相物及其在人体口腔中停留不同时间后的光电离质谱图,并根据定性分析结果,对质荷比(m/z)30、44、54、58、68、78、94和106所对应的主要烟气有害化学成分(一氧化氮、乙醛、1,3-丁二烯、丙酮、异戊二烯、苯、苯酚和乙苯)在口腔中的残留效率进行了对比分析。结果表明:(1)当卷烟烟气在口腔中停留2 s时,醛酮类化合物具有较高的口腔残留效率,其次为苯酚,而一氧化氮及1,3-丁二烯等不饱和烃类物质则具有相对低的口腔残留效率。(2)在26 s内,随着烟气在口腔中停留时间的延长,醛酮类化合物的口腔残留效率一直快速上升,其余化合物的残留效率则在最初的10~14 s内快速上升,随后变化不明显。真空紫外光电离飞行时间质谱实现了从吸烟机和人体口腔中直接取样分析,可作为研究卷烟烟气中有害化学成分口腔残留的有效工具。     

低焦油卷烟加香后一些醛酮类香料转移行为

以同一叶组生产的普通空白卷烟和低焦油空白卷烟为研究对象,采用同时蒸馏萃取及气相色谱（GC）和气相色谱/质谱联用（GC/MS）方法,测定了19种醛酮类香料单体在加香卷烟中的主流烟气粒相转移率、烟丝持留率、滤嘴截留率和滤嘴迁移率,发现醛酮类香料单体在2种卷烟中的烟丝持留率和滤嘴迁移率整体差别不大,低沸点香料由于其较强的透发性在卷烟的主流烟气粒相中转移率显著低于高沸点香料。具有相同官能团的同系物,碳链越长,分子量越大沸点越高,烟丝持留率和主流烟气粒相转移率越高,而滤嘴截留率和滤嘴迁移率有先增大后减小的趋势。低焦油卷烟在采取通风降焦措施的同时,外加香料在主流烟气粒相中的转移率显著低于在普通卷烟中的转移率,且降低幅度随香料沸点增大而减小,香料沸点越低,在主流烟气粒相中的转移率降低幅度也越大。     

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