卷烟烟气在模拟口腔环境中pH值的测定

针对卷烟烟气酸碱性评价提出了在模拟口腔环境中检测卷烟烟气pH值的方法,采用剑桥滤片收集卷烟主流烟气总粒相物,用模拟口腔溶液震荡萃取滤片,pH复合电极测定萃取溶液的pH值,建立了检测卷烟主流烟气酸碱性的方法。将测定结果与卷烟主流烟气常规成分含量和卷烟评吸结果进行简单相关分析。结果表明:①主流烟气pH值与卷烟烟气总粒相物、焦油、烟气烟碱、烟气水分均具有较高的相关性,与卷烟抽吸口数基本不存在相关性;②主流烟气的pH值与卷烟的烟气特性(烟气浓度、丰富性)、口味风格(甜味、苦味)、舒适感特性(刺激感、收敛、残留/干燥感)得分呈显著相关关系,与卷烟的口味风格—酸性相关性不强。     

中心切割二维气相色谱法测定卷烟主流烟气中的硝基苯

建立了环己烷萃取、硅胶固相萃取柱净化和中心切割二维气相色谱法测定卷烟主流烟气粒相物中硝基苯的方法,并采用该法测定了6种卷烟样品主流烟气中的硝基苯释放量。结果表明:①中心切割技术有效提高了色谱的分离能力,使得痕量硝基苯可以从复杂的烟气基质中分离出来,分离效果明显优于一维色谱;②方法的检测限为1.28 ng/mL,相对标准偏差(RSD)6.82%,回收率87.6%;③6种卷烟主流烟气中硝基苯的释放量为0.091~1.66 ng支/。     

振荡萃取-GC/MS法测定卷烟主流烟气总粒相物中的14种挥发性有机酸

建立了同时测定卷烟主流烟气总粒相物中甲酸、乙酸和癸酸等14种挥发性有机酸的振荡萃取-气相色谱-质谱联用(GC/MS)方法。捕集了卷烟主流烟气总粒相物的剑桥滤片经添加乙酸苯乙酯内标后,用甲醇振荡萃取,在选择离子监测模式下进行GC/MS分析。结果表明:方法的检出限(LOD)和定量限(LOQ)分别为0.08~3.00和0.26~10.00μg/支,加标回收率为97.5%~110.8%,相对标准偏差为1.2%~8.5%。该方法适用于卷烟主流烟气总粒相物中甲酸、乙酸和癸酸等14种挥发性有机酸的测定。      

卷烟主流烟气粒相物pH测定方法研究

通过研究卷烟主流烟气粒相物pH测定的影响因素,建立卷烟主流烟气粒相物pH测定方法,为卷烟感官品质提供理论支撑。按照标准条件在吸烟机上抽吸10支卷烟并用剑桥滤片捕集粒相物,转移至150mL锥形瓶中,并用pH计测定其pH。试验考查了抽吸烟支数、萃取液体积、萃取液浓度以及萃取时间对主流烟气粒相物pH的影响,并采用正交试验进行了条件优化。结果表明:抽吸烟支数为10支;萃取剂为90mL50%异丙醇;萃取时间为30min。利用该方法对国内10个牌号卷烟样品主流烟气粒相物pH进行测定,其RSD在0.16%~0.48%之间,测定方法简单、方便、精密度和灵敏度较高,适用于测定卷烟主流烟气粒相物pH。     

通风、加长滤嘴对卷烟主流烟气粒相物中挥发性、半挥发性酸性成分释放量的影响

卷烟主流烟气粒相物经二氯甲烷浸提,进行GC/MS分析,对通风、加长滤嘴后卷烟主流烟气粒相物中21种挥发性、半挥发性酸性成分的变化进行了分析研究。结果表明:通风度20%卷烟2、5 mm滤嘴卷烟与参比卷烟(20 mm滤嘴、不打孔)相比,21种酸性成分总量分别减少了22.1%、26.3%。通风、加长滤嘴后卷烟主流烟气粒相物中不同酸性成分减少的程度不同,分子量较小、沸点较低的物质减少较多,而分子量较大、沸点较高的物质减少较少。     

卷烟主流烟气和侧流烟气中半挥发性成分的分析研究

本文对5个牌号国产商品卷烟主流烟气(MS)与侧流烟气(SS)中的半挥发性成分进行了分析研究。卷烟主流烟气总粒相物采用标准方法捕集;卷烟侧流烟气总粒相物采用鱼尾罩装置来收集。采用同时蒸馏萃取前处理分离方法和气相色谱、气质联用分析技术对总粒相物中的半挥发性成分进行了分析。定性分析了主流烟气和侧流烟气中的87种成分;采用内标法对其中38种成分的含量进行了定量分析,测定了这38种成分在侧流烟气与主流烟气中的分配比,并对结果进行了讨论。研究结果表明,卷烟主流烟气和侧流烟气中半挥发性成分种类基本相同,但每种成分的含量有很大的差异;普通卷烟侧流烟气中半挥发性成分的总量明显高于主流烟气,大多数半挥发性成分的侧流烟气含量高于主流烟气。低侧流卷烟侧流烟气中半挥发性成分总量明显低于主流烟气,证实了低侧流卷烟能减少对环境的烟气释放量。      

分散液液微萃取-GC-MS/MS法测定卷烟主流烟气粒相物中的农药残留

为测定卷烟主流烟气粒相物中的农药残留,通过考察优化萃取剂种类、萃取剂体积、萃取时间等因素,建立了检测卷烟主流烟气粒相物中63种农药残留的分散液液微萃取(DLLME)-气相色谱-串联质谱(GC-MS/MS)方法。用乙腈振荡萃取捕集主流烟气粒相物后的剑桥滤片,萃取液进行DLLME处理,取四氯化碳相进行GC-MS/MS测定,内标法定量。结果表明:63种农药在各自的线性范围内线性关系良好(R2=0.994 9~1.000 0),目标物定量限均≤10 ng·支-1;在高、中、低3个加标水平下,农药的平均回收率为75.6%~127.5%,相对标准偏差为0.5%~19.0%。该方法简单、准确,灵敏度高,适用于卷烟主流烟气粒相物中63种农药残留的测定。     

HS-SPME-GC/MS法测定主流烟气中8种香味成分的逐口释放量

建立了测定卷烟主流烟气粒相物中香味成分的顶空-固相微萃取-气相色谱-质谱(HS-SPME-GC/MS)方法,并采用该方法定量测定了卷烟主流烟气中8种香味成分(吡啶、吡咯、糠醛、5-甲基糠醛、3-甲基吡啶、D-柠檬烯、2,3,5,6-四甲基吡嗪和β-大马酮)的逐口释放量。结果表明:1选用85μm碳分子筛/聚二甲基硅氧烷(CAR/PDMS)的固相微萃取头、萃取温度及时间为60℃和60 min、解吸温度及时间为250℃和8 min时,固相微萃取的效率最高;2在优化条件下,8种香味成分标样的工作曲线线性相关系数、相对标准偏差及加标回收率分别为0.969 8~0.999 5、3.8%~9.0%和78%~105%;3在卷烟燃吸过程中香味成分与烟碱的主流烟气递送规律存在明显的区别。随着抽吸口序的增加,主流烟气中总粒相物和烟碱释放量呈上升趋势,而8种香味成分的逐口主流烟气释放量比较平稳。     

离子色谱-脉冲安培法检测卷烟主流烟气中的 6 种水溶性糖

阿拉伯糖、半乳糖、葡萄糖、木糖、甘露糖和果糖是卷烟主流烟气中的6种主要水溶性糖。采用高效阴离子交换色谱-脉冲安培检测法对这6种水溶性糖进行了分离测定。优化了样品提取方法。捕集在剑桥滤片上的主流烟气中的水溶性糖用20 mg/L NaN3水溶液超声提取45 min,在分析前无需进行其它前处理。用2.5 mmol/L NaOH作为流动相在CarboPac PA20色谱柱上实现了对6种糖的有效分离。6种水溶性糖的的检测限在2.47-9.82 μg/L之间,线性相关系数均大于0.999,日内精密度小于5.0%,日间精密度小于6.9%,高、中、低三种添加水平的回收率在97.1%-102.4%之间。方法成功应用于多个牌号卷烟样品的检测。在所测定的样品中,6种水溶性糖的含量在36.17 ？g/支和119.5μg/支之间。果糖含量最高,为24.63-74.66μg/支。其次为葡萄糖,为8.09-38.09 μg/支。果糖和葡萄糖占了6种糖总量的90.5-94.7%。     

UPLC-MS/MS测定卷烟烟气、滤嘴和烟灰中5种常用杀菌剂及其转移行为研究

建立了UPLC-MS/MS测定主流烟气总粒相物、气相物、滤嘴、烟蒂烟丝和烟灰中霜霉威、多菌灵、稻瘟灵、三唑醇和三唑酮含量的方法,样品经乙腈或甲醇提取,分散固相萃取后,进行UPLC-MS/MS分析。5种杀菌剂在各基质中的检出限为0.325~1.832ng/cig,平均回收率为90.9%~111.8%,RSD为1.3%~10.1%。应用该方法研究了标准卷烟加标样品和自然高残留样品中杀菌剂的烟气转移率,结果表明:标准卷烟加标样品中,5种杀菌剂向主流烟气总粒相物、滤嘴中的平均转移率分别为29.4%和11.0%,向烟蒂烟丝和烟灰中平均转移率为1.6%和0.2%,主流烟气气相物中则未检出杀菌剂;主流烟气总粒相物中,多菌灵的转移率较低（<5%）,其它4种杀菌剂则接近或超过30%。自然高残留卷烟样品中,5种杀菌剂向烟气总粒相物中平均转移率为3.7%,在滤嘴中平均转移率为2.2%。卷烟实际燃吸过程中5种杀菌剂向烟气总粒相物转移率明显低于加标研究结果;若采用加标研究结果,成品卷烟杀菌剂残留对吸烟者的健康风险将被高估。      

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