用电子鼻研究不同烘丝过程对卷烟挥发性成分的影响

采用电子鼻对卷烟烟丝挥发性组分进行分析,分别考察了前处理制样与电子鼻顶空平衡时间对结果的影响。确定采用三包卷烟的烟丝作为大样本,混合均匀后称取适量样品直接电子鼻分析,电子鼻顶空平衡温度为55℃。应用电子鼻在该参数下对不同烘丝方式和温度参数处理的卷烟烟丝挥发性成分进行气味指纹图谱和PCA分析,同连续流动法测定的常规化学成分结果作了比较,结果表明电子鼻能够反映规常规化学成分检测手段不能区分的不同烘丝过程带来的挥发性组分改变。     

芜菁子挥发油GC-MS指纹图谱的建立

建立新疆芜菁子药材挥发油的GC-MS指纹图谱,为芜菁子药材的质量评价和鉴定提供基础数据。应用气相色谱-质谱联用技术对10批次芜菁子挥发油进行指纹图谱分析,采用指纹图谱软件及SPSS统计软件对10批次芜菁子挥发油的数据进行相似度评价及聚类分析。GC-MS指纹图谱符合技术要求,重现性、精密度和稳定性都较好,聚类分析结果可分为3大类。方法简单、准确可行,可为芜菁子药材的质量控制和鉴定提供了科学依据。     

应用近红外光谱技术分析烟丝总糖和还原糖的研究

应用傅立叶变换近红外漫反射光谱仪,对同一品牌通过选择不同批号代表性好的卷烟烟丝样品,建立了卷烟烟丝总糖和还原糖的近红外定量分析数学模型,并对不同批号的分析样品进行检验,近红外预测值的平均相对误差为1.01%和0.77%,接近实测值,说明近红外光谱分析技术可用于卷烟烟丝生产质量指标的检测.     

近红外光谱结合模式识别方法所建模型分析卷烟烟丝配方比例北大核心CSCD

为卷烟配方替代和产品质量稳定性评价奠定基础,利用近红外光谱结合模式识别方法,建立了卷烟烟丝配方比例的识别模型。在某牌号卷烟成品烟丝中添加5种不同比例的A模块烟丝,采集其近红外光谱信息,采用求导法(一阶求导、二阶求导)和平滑法(Savitzky-Golay平滑、Norris平滑)对样品近红外光谱进行预处理,结合主成分分析-马氏距离(PCA-MD)、偏最小二乘法-判别分析(PLS-DA)和正交偏最小二乘法-判别分析(OPLS-DA)建立上述5种成品烟丝的识别模型。结果显示,最佳光谱预处理方式为一阶求导+Savitzky-Golay平滑,最佳模式识别方法为OPLS-DA。当主成分数为4时,最佳识别模型的光谱变量累计解释能力为0.995,分类变量累计解释能力为0.953,特征值为0.196,累计交叉有效性为0.912,模型外部验证的整体识别率为99%。置换验证结果表明该模型稳定可靠,未出现过拟合现象。对5种成品烟丝进行感官评吸,该模型对不同卷烟烟丝配方比例的识别效果更好。     

指纹图谱结合化学计量学方法研究新疆薰衣草精油成分

采用水蒸汽蒸馏法(SD)提取薰衣草挥发油,气相色谱-质谱联用(GC-MS)技术分析其化学成分及相对含量。通过气相色谱法(GC)建立其色谱指纹图谱,并结合化学计量学方法对其进行品种鉴别。3种薰衣草精油中共检测29种挥发性化学成分,其中共有成分有18种;31批薰衣草样本的GC指纹图谱相似度均大于0.9,符合指纹图谱相似度的要求,利用主成分分析法(PCA)和聚类分析法(HCA)对GC指纹图谱进行识别,可直观地区分薰衣草品种,该方法可应用于薰衣草质量控制及品种鉴别。     

近红外光谱技术在快速检验制丝过程中烟丝质量均一性上的应用北大核心CSCD

采用近红外光谱技术结合主成分分析-马氏距离法研究了卷烟制丝工艺过程中掺配、加香、贮丝及喂丝等4个工序段中烟丝样品的质量均一性。用主成分分析法提取近红外光谱所包含的特征信息,较全面地反映制丝过程4个不同取样点样本的离散程度,马氏距离可反映制丝过程中烟丝质量的波动情况。此外,采用成品烟丝的模型预测了取样点D处烟丝样品中6种化学成分(总植物碱、总糖、还原糖、总氮、钾和氯)的含量,使不同批次的烟丝样品中化学成分的差异控制在合理范围,降低批次间卷烟产品化学成分含量的波动,能有效稳定品牌香烟的特征风格。     

气相色谱-质谱指纹图谱在甄别真假卷烟上的应用

运用固相微萃取／气相色谱-质谱法建立卷烟挥发性和半挥发性物质的指纹图谱。通过指纹图谱相似度评价软件,对12批正品卷烟和1个假冒品卷烟的指纹图谱进行了相似度计算,结果表明：12批样品间相似度很好,而假冒品卷烟与正品卷烟的相似度很低,该方法为探讨卷烟质量稳定和甄别真假卷烟提供了一种简便易行的方法模式。     

近红外光谱技术在快速检验制丝过程中烟丝质量均一性上的应用

采用近红外光谱技术结合主成分分析-马氏距离法研究了卷烟制丝工艺过程中掺配、加香、贮丝及喂丝等4个工序段中烟丝样品的质量均一性。用主成分分析法提取近红外光谱所包含的特征信息,较全面地反映制丝过程4个不同取样点样本的离散程度,马氏距离可反映制丝过程中烟丝质量的波动情况。此外,采用成品烟丝的模型预测了取样点D处烟丝样品中6种化学成分(总植物碱、总糖、还原糖、总氮、钾和氯)的含量,使不同批次的烟丝样品中化学成分的差异控制在合理范围,降低批次间卷烟产品化学成分含量的波动,能有效稳定品牌香烟的特征风格。     

卷烟原料的保润性能研究

采用烘箱法、动态水分吸附分析系统、气相色谱-质谱联用仪(GC-MS)以及电子扫描显微镜技术比较了卷烟原料保润性的差异。结果表明:1原料烟丝平衡含水率为12.68%,膨胀丝为12.45%,混合丝为12.07%,梗丝为11.99%,而且依据不同原料自身结构的不同,填充值差异性明显。2由于原料微结构存在明显性差异,烟丝失水率为7.24%,膨胀丝为7.61%,混合丝为8.37%,梗丝为11.95%,表明了烟丝的物理保润性效果较好。3综合分析原料挥发性成分及含量,烟丝与膨胀丝致香成分含量较多,混合丝次之,梗丝较少。     

固相微萃取气质联用技术对卷烟烟丝和卷烟烟气总粒相物中挥发性和半挥发性成分的研究

采用固相微萃取－气相色谱－质谱（SPME－GC－MS）法对成品卷烟烟丝和卷烟烟气总粒相物中挥发性和半挥发性成分进行了分析鉴定，并对鉴定出的70种成分和96种成分进行了比较。     

Development of solid-phase microextraction followed by gas chromatography-mass spectrometry for rapid analysis of volatile organic chemicals in mainstream cigarette smoke

In this work, a novel, simple and efficient method based on solid-phase microextraction (SPME) followed by gas chromatography-mass spectrometry (GC-MS) was developed to the analysis of volatile organic chemicals (VOCs) in mainstream cigarette smoke (MCS). Using a simple home-made smoking machine device, extraction and concentration of VOCs in MCS were performed by SPME fiber, and the VOCs adsorbed on fiber were desorbed, and analyzed by GC-MS. The extraction fiber types and the desorption conditions were studied, and the method precision was also investigated. After the investigation, the optimal fiber was divinylbenzene/carboxen/polydemethylsiloxane (DVB/CAR/PDMS), and the optimal desorption condition was 250 degrees C for 3 min. The method precision was from 2% to 11%. Finally, the proposed method was tested by its application of the analysis of VOCs in MCS from 10 brands of cigarettes and one reference cigarette. A total of 70 volatile compounds were identified by the proposed method. The experimental results showed that the proposed method was a simple, rapid, reliable, and solvent-free technique for the determination of VOCs in MCS.     

Application of headspace solid phase microextraction to qualitative and quantitative analysis of tobacco additives in cigarettes

Cigarettes may contain up to 10% by weight additives which are intended to make them more attractive. A fast and rugged method for a cigarette-screening for additives with medium volatility was developed using automatic headspace solid phase microextraction (HS-SPME) with a 65 microm carbowax-divinylbenzene fiber and gas chromatography-mass spectrometry (GC-MS) with standard electron impact ionisation. In three runs, each cigarette sample was extracted in closed headspace vials using basic, acidic and neutral medium containing 0.5 g NaCl or Na2SO4. Furthermore, the method was optimized for quantitative determination of 17 frequently occurring additives. The practical applicability of the method was demonstrated for cigarettes from 32 brands.     

Quantitative analysis of acetates in cigarette tobacco using solid-phase microextraction and gas chromatography-mass spectrometry

A method incorporating solid-phase microextraction (SPME) and gas chromatography-mass spectrometry for the headspace analysis of selected volatile organic compounds present in cigarette tobacco is developed and evaluated. Quantitative information on methyl, ethyl, n-propyl, isopropyl, isopropenyl, vinyl, and butyl acetates present in 29 different flavor variants (full, light, and ultra-light) of the top ten selling brands in the United States is presented. The concentrations of the various acetate analytes range from the low nanaogram to microgram levels per cigarette. Clear differences are observed in the concentrations of various acetates when comparing the levels in brands from different manufacturers. The SPME technique provides a method that allows high sample throughput, requires little sample preparation, and yields useful analytical information. High precision is obtained on multiple measurements of cigarettes from an individual pack, but lower precision levels are observed in general when comparing results obtained on the analysis of cigarettes from different packs of the same brand. The higher pack-to-pack variations may be due in part to product aging with a proportionate amount of evaporative loss of the relatively volatile acetates.     

Optimization and validation of a gas chromatographic method for analysis of (RS,SR)-diastereoisomeric impurity in formoterol fumarate

The levels of 2-amino-9H-pyrido[2,3-b]indole (AalphaC or 2-amino-alpha-carboline), 2-amino-3-methyl-9H-pyrido[2,3-b]indole (MeAalphaC or 2-amino-3-methyl-alpha-carboline), 9H-pyrido[3,4-b]indole (norharman), and 1-methyl-pyrido[3,4-b]indole (harman) have been determined in the mainstream smoke condensate from three reference cigarettes, namely Kentucky reference 1R5F, Kentucky reference 2R4F, and CORESTA CM4. The amino-alpha-carbolines, and norharman and harman (beta-carbolines) can be classified as heterocyclic aromatic amines (HAAs) and are listed as biologically active agents in the mainstream smoke of cigarettes. For the analysis, the mainstream smoke condensate from cigarettes was collected on a filter pad, the analytes were isolated using solid-phase extraction (SPE), and quantified without derivatization on a GC-MS. Total amounts of carbolines found in the condensate increased from ultralight 1R5F to full-flavor CM4 cigarettes. The level of harman was about 250 ng/cigarette for the 1R5F cigarette and about 1025 ng/cigarette for the CM4 cigarette. Norharman was typically three times more abundant than harman. The AalphaC was found at about 10 times lower level compared to harman, and MeAalphaC was about 50 times lower than harman. The use of reference cigarettes can provide a common measure for laboratories to assess carboline amounts among cigarette brands.     

Solid phase microextraction of alkenylbenzenes and other flavor-related compounds from tobacco for analysis by selected ion monitoring gas chromatography-mass spectrometry.

Some constituents found in natural flavorings are known to exhibit toxic properties. We developed a rapid method for quantifying 12 flavor-related compounds in cigarette tobacco using headspace solid-phase microextraction coupled with gas chromatography-mass spectrometry. Using selected ion monitoring, we quantified and positively identified coumarin; pulegone; piperonal and nine alkenylbenzenes, including trans-anethole, safrole, methyleugenol and myristicin in one or more brands of cigarettes. In 62% of 68 brands analyzed, we detected one or more of the flavor-related compounds ranging from 0.0018 to 43 microg/g. Toxic properties of these flavor-related compounds may constitute an additional health risk related to cigarette smoking.     

卷烟烟气中挥发性组分的毛细管气相色谱分析

采用毛细管气相色谱（CGC）和色谱－质谱联用（GC－MS）技术对国内外部分名牌卷烟烟气中的挥发性和半挥发性化学成分进行了定性定量分析,质谱鉴定出107种化合物;对其中重要的32种化合物进行了定量比较,结果发现烤烟型卷烟、混合型卷烟和英式烤烟在烟气的香味组分中存在一些差异和规律,烤烟型烟气组分总含量最高,烤烟烟气中碳氢化合物裂解产物和低级酸类组分含量较高,混合型卷烟烟气中茄酮和异戊酸较高,英式烤烟的烟气组分更接近于混合型卷烟。     

Multivariate classification of cigarettes according to their elemental content determined by inductively coupled plasma optical emission spectrometry.

In this paper we describe our study on the characterization of cigarette samples according to their mineral content. Acid digestion assisted by microwaves was employed, and inductively coupled plasma optical emission spectrometry was the analytical technique used for the determination of Al, Ba, Ca, Cu, Fe, K, Mg, Mn, Na, P and Sr in conventional, light, and flavorized cigarettes. Multivariate techniques, such as hierarchical clusters analysis (HCA) and principal-component analysis (PCA), were applied to discriminate among different types of cigarettes. Cluster analysis and principal-component analysis showed differences in cigarettes according to the type and mineral composition. The cigarette samples were divided within the 3 groups according to their mineral composition. Ca, Sr, Cu, K and Na were the most important elements for cigarette classification, and only these 5 variables were sufficient for the classification and discrimination of the evaluated types of cigarettes.     

离子色谱法及聚类分析研究主流烟气中的有机酸

建立了超声辅助萃取-离子色谱法同时测定卷烟主流烟气中主要有机酸的方法.采用20 mL 30 mmol/L J NaOH溶液在50℃下对捕集了卷烟主流烟气的剑桥滤片超声萃取50 min,AS11-HC分离柱、Ion AG11-HC保护柱、ASRS-ULTRAⅡ抑制器,KOH溶液为淋洗液,用电导检测器同时测定了卷烟主流烟气中的乳酸、甲酸、乙酸、丙酸、苹果酸和草酸的含量.方法的线性范围1.0～400 mg/L,相关系数为0.9990～0.9995,相对标准偏差1.4%～4.8%,检出限0.03～0.09 mg/L,回收率为92%～104%.采用此方法测定了19种不同规格卷烟样品主流烟气中6种有机酸的含量,并且以6种有机酸为指标对样品进行了聚类分析.结果表明,6种有机酸的含量分布特征可反映不同等级卷烟产品的特性,可用于不用等级卷烟产品的比较和分类.     

Analysis of pyridines in mainstream cigarette smoke

A new technique has been developed for the quantitative analysis of pyridines in mainstream cigarette smoke using a GC-MS technique. For analysis, 10 cigarettes are smoked using conditions based on US Federal Trade Commission recommendations. The smoke is collected in a water trap and analyzed using a GC-MS technique. A standard or a fast GC separation can be applied for the analysis. The standard separation was followed by MS detection using selected ion monitoring (SIM) acquisition on a quadrupole instrument. The fast GC was followed by MS detection with total ion acquisition on a time-of-flight instrument. The levels of pyridine depend on the type of cigarette: for a full flavor cigarette pyridine is as high as 18.0 microg/cigarette (cig.). and for an ultra light cigarette is about 3.0 microg/cig. Substituted pyridines vary between 5.0 microg/cig. to 0.1 microg/cig. for a full flavor cigarette, and between 0.2 microg/cig. and a few ng/cig. for an ultra light cigarette. The reproducibility of the technique is very good, with less than 7-8% RSD in both separation procedures for most of the analyzed compounds.     

Simultaneous determination of four tobacco-specific N-nitrosamines in mainstream smoke for Chinese Virginia cigarettes by liquid chromatography-tandem mass spectrometry and validation under ISO and “Canadian intense” machine smoking regimes

A liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for determining four tobacco-specific N-nitrosamines (TSNAs) in mainstream smoke from Chinese Virginia cigarettes was developed. Mainstream cigarette smoke particulate matter was collected on a Cambridge filter pad, further extracted using 100 mM ammonium acetate after 100 μL internal standard addition, and subsequently analyzed with LC-MS/MS. The limit of detection for NNN, NNK, NAT and NAB were 0.006, 0.013, 0.003 and 0.021 ng mL⁻¹ respectively, with a linear calibration range spanning 1-200 ng mL⁻¹. Intra- and inter-day precision for four TSNAs ranged from 3.3% to 8.5% and 2.3% to 10.1%; recovery was between 89.1% and 104.9% for Chinese Virginia cigarettes. The proposed method was applied to evaluate TSNAs yields for 39 commercially available cigarettes in Chinese market under ISO and “Canadian intense” machine smoking regimes, on the ground that it comes closest to representing smoke deliveries from human smoking. Total TSNAs emissions are more than double under the Canadian regime. TSNAs:nicotine ratios were used in our assay to show any differences in yield from different brands. TSNAs:nicotine levels show more than a 10-fold difference across brands and types (Chinese Virginia cigarettes and blended cigarettes) in the Chinese market.