In order to investigate the effects of organic acids on releasing behavior of nicotine in heated tobacco products with randomly cut tobacco filling, GC-MS analysis method was used to analyze the influences of adding different mass fractions of citric acid, tartaric acid, malic acid,levulinic acid, lactic acid, propionic acid and acetic acid on the transfer rate of total nicotine, the pH of aerosol and the forms of nicotine in the aerosol of a heated tobacco product. The results showed that: 1) The addition of these organic acids did not affect the transfer rate of total nicotine significantly. 2) The p H of aerosol also did not change significantly after adding the non-volatile organic acids; however it decreased slightly and continuously with the increase of volatile organic acids. 3) The proportion of free nicotine in the aerosol was not significantly influenced by the addition of non-volatile organic acids, while it decreased obviously and continuously with the addition of volatile organic acids.

采用卷烟烟气口腔沉积模拟装置,对25种卷烟样品主流烟气主要挥发性羰基物的模拟口腔沉积情况进行了分析.结果表明:①各挥发性羰基物分析结果的日内、日间相对标准偏差均小于15％,大部分小于10％,模拟装置对挥发性羰基物的口腔沉积分析的稳定性良好.②不同挥发性羰基物的口腔沉积量由大到小依次为乙醛、甲醛、丙酮、丙醛、丙烯醛、丁醛、巴豆醛和2-丁酮,其中,甲醛和乙醛的沉积量显著高于其他挥发性羰基物;沉积比例由高到低依次为甲醛、乙醛、丙醛、丁醛、巴豆醛、丙烯醛、丙酮和2-丁酮.③烟气口腔刺激与甲醛、乙醛口腔沉积量显著负相关,相关系数分别为-0.916、-0.934,P值均小于0.01.

为从化学的角度监控α,β-不饱和醛类香料的产品质量,通过温度因素实验结合GC/MS方法考察了7种α,β-不饱和醛类香料转化产物的化学组成;针对主要转化产物α,β-不饱和酸建立了GC/MS定量分析方法,并测试了实验室存放的11个烯醛类香料样品.结果表明:①该方法简单、灵敏度高(LODs<0.12μg/mL)、精密度好(RSDs<4.5％);②不同实验室存放的α,β-不饱和醛类香料产品中α,β-不饱和酸类物质的质量分数介于15.8～450.6 mg/g之间,且存放越久,质量分数越高,这与温度因素实验结果一致;③α,β-不饱和酸或可作为α,β-不饱和醛类香料化学品质改变的标志物用于产品质量监控.

采用相同叶组和辅材卷制了短支(烟支长75 mm)与常规(烟支长84 mm)两种卷烟样品,分析了两种卷烟样品主流烟气常规成分、焦甜香成分、烟熏香成分和有机酸类香味成分的逐口释放情况及差异.结果表明:①短支和常规卷烟主流烟气TPM、焦油、烟碱和水分的逐口释放量均随抽吸口数序号的增加而升高,但短支卷烟的逐口释放量均明显高于常规卷烟.②释放量相对较高的焦甜香成分依次为糠醇、甲基环戊烯醇酮、麦芽酚、4-羟基-2,5-二甲基-3(2H)-呋喃酮;焦甜香成分的逐口释放量随抽吸口数序号的增加大部分呈先增加后减小趋势;短支卷烟逐口单位焦油释放量低于常规卷烟.③释放量相对较高的烟熏香成分依次为对甲酚、2-(4-羟基苯基)乙醇、邻甲酚、2,6-二甲氧基苯酚、苯酚;烟熏香成分的逐口释放量随抽吸口数序号的增加大部分呈先增加后减小趋势;短支卷烟前4 口的逐口释放量明显高于常规卷烟,第5 口明显低于常规卷烟;短支卷烟第5 口的单位焦油释放量明显低于常规卷烟.④释放量相对较高的有机酸类香味成分依次为羟基乙酸、乳酸和丙酮酸;有机酸类香味成分的逐口释放量随抽吸口数序号的增加大部分呈上升趋势;短支卷烟的逐口释放量均明显高于常规卷烟.

采用硅胶柱层析结合制备液相从巴戟天(Morinda officinalis)中分离得到8个蒽醌类化合物.根据化合物的波谱数据并与文献对照进行了结构鉴定,分别为2-羟甲基-3-羟基蒽醌(2-hydroxymethyl-3-hydroxyanthraquinone,1)、3-羟基-2-羟甲基-1-甲氧基蒽醌(3-hydroxy-2-hydroxymethyl-1-methoxyanthraquinone,2)、2-羟基-1-甲氧基蒽醌(2-hydroxy-1-methoxyanthraquinone,3)、3-羟基-1,2-二甲氧基蒽醌(3-hydroxy-1,2-dimethoxyanthraquinone,4)、甲基异茜草素-1-甲醚(rubiadin-1-methyl ether,5)、1,3-二羟基-2-甲氧基蒽醌(1,3-dihydroxy-2-methoxyanthraquinone,6)、1,3-二羟基-2-乙氧甲基蒽醌(ibericin,7)、1,2-二羟基-3-甲基蒽醌(1,2-dihydroxy-3-methylanthraquinone,8).其中蒽醌(2)为首次从该植物中分得.利用MTr法对分离出的蒽醌的体外抗癌活性进行筛选,结果显示蒽醌(3)、(5)和(7)对肝癌细胞SMMC-7721增殖有明显的抑制作用,当蒽醌的浓度为400 μmol/L时,蒽醌(3)、(5)和(7)对肝癌细胞的抑制率分别为44.63％、20.52％、54.89％.

In order to develop a new approach for preparing flavors by Maillard reaction, molar concentrations of soluble sugars and free amino acids in water extracts of sweet potato, pumpkin and potato and pHs of the extracts were quantified. Three natural flavors were produced via the Maillard reaction of these water extracts. The aroma components in roasted sweet potato, pumpkin and potato were compared with those in corresponding natural flavors respectively. The potentials of the three natural flavors for improving the smoking quality of cigarette were verified by laboratory pyrolysis analysis and human sensory evaluation. The results showed that:1)Realistic and coordinated roasted sweet potato flavors(GS), roasted pumpkin flavors(NG)and roasted potato flavors(TD)could be prepared by using water extracts of the natural plants. 2)The main aroma components and volatile pyrolysis products in GS and NG were furans, furanones, pyranones and cyclopentenones compounds, and roasted sweet aroma was the main aroma characteristic of GS and NG.Adding GS and NG onto cut tobacco could strengthen the roasted sweet aroma note of cigarette smoke. 3)The main aroma components and volatile pyrolysis products in TD were pyrazines, pyrroles and pyridines compounds, and baked aroma was the main aroma characteristic of TD. Adding TD provided an outstanding baked aroma in cigarette smoke.

The formation of 5-hydroxymethylfurfural was investigated in the Maillard reaction system of alanine and glucose with different thermal time and initial pH.The HMF was determined by HPLC.The results show that,the content of HMF increased with the increasing of heating time.The formation of HMF was in accordance with zero-order kinetics in 3-12 h.The maximum amount was 0.122 μg/mL at the 12 h.The acidic pH conditions promoted the formation of HMF,while alkaline pH conditions inhibited.The pH value of the Maillard reaction,on which the heating time and the initial pH had less effect,was between 4.0-5.0.

In order to control exogenous contamination risks for raw materials used in oral tobacco products, a qualitative and quantitative analysis method for polychlorinated biphenyls(PCBs)in tobacco leaves was established. The developed method for the simultaneous determination of seven PCBs in tobacco by gas chromatography-mass spectrometry(GC-MS)was applied to test 42 domestic and imported tobacco samples. After extraction, vacuum concentration to drying, re-dissolving and purification, the tobacco powder samples were quantified by gas chromatography-mass spectrometry(GC-MS)with internal standards. The results showed that: 1)The linearity of curves of the seven PCBs'concentration-response relationship was good with the correlation coefficient range between 0.984 3-0.994 8. 2)The limit of detection and the limit of quantification were 0.22-1.07 and 0.73-3.57 ng·mL-1, respectively. The spiked recovery ranged from 70.4% to 95.5% with the intra-day and inter-day relative standard deviations no more than 4.6% and 9.2%, respectively. 3)Different amounts of the seven PCBs were detected in the 42 samples with the maximum total amount of 0.37 mg·kg-1, which was lower than the limit level of PCBs in food(≤0.5 mg·kg-1in total). This method is simple, rapid and suitable for the detection of PCBs in tobacco samples.

In order to investigate the effects of heating temperature on the release of smoky components in aerosol from heat-not-burn tobacco products(HnBs),26 smoky components generated from 3 types of HnBs were determined and compared with those from traditional cigarette smoke. The tobacco of HnBs was heated at different temperatures,and the types and release of smoky components in aerosol were analyzed. The results showed that:1)There were fewer types of smoky components released from HnBs than from traditional cigarette,and the release levels of smoky components from HnBs were also lower. 2)The type and release of smoky components from HnBs significantly increased with the rise of heating temperature. 3)The release of guaiacol,4-vinyl guaiacol and isoeugenol increased quickly when heating temperature rose to 250 ℃; and the release of phenol and o-cresol significantly increased when heating temperature rose to 300 ℃-350 ℃. The constituents of smoky components of HnBs aerosol greatly differs from those of cigarette smoke,and heating temperature is a key factor influencing the release of smoky components from HnBs.

In order to investigate the influences of reaction conditions on the formation of volatile compounds from a model Maillard reaction of glucose and glutamic acid in aqueous solutions, the changes of pH and UV-visible absorbance at different reaction conditions were analyzed. Furthermore, the generated volatile compounds under different reactant ratios, reaction times and solvents were identified by GC/MS. The results indicated that: 1) The UV-visible absorbance A294 nm and A420 nm increased with the increases of glutamic acid content in the model system, propanediol in solvent and reaction time, while A294 nm/A420 nm decreased. 2) The total amount of volatile compounds, and the yields of pyridines, pyrazines, pyrroles, furans, furanones, organic acids and carbocyclic compounds increased, while the yields of pyranones, esters and aliphatic compounds increased at first and then decreased with the prolonged reaction time. When the content of glutamic acid increased in glucose/glutamic acid model system, the total amount of volatile compounds and the generation of pyridines, pyrroles, furans, furanones, esters, carbocyclic compounds and pyranones increased. The yields of volatile compounds increased with the increase of propanediol content in solvent, except for esters and aliphatic compounds.

To study the levels of solvent residues in plant extracts, 27 residual solvents in 15 samples of 5 types of extracts (medlar, hawthorn, chrysanthemum, jasmine, osmanthus) were qualitatively and quantitatively analyzed by static headspace (HS) combined with GC-MS. The samples were dissolved in headspace vials and kept warm at 60 ℃ for 15 min. A sample of 0.40 mL headspace volatiles was injected into GC-MS using external standard for peak identification. NIST database and standards plus internal standards were used for qualitatively and quantitatively analyses, respectively. The results showed that: 1) The linear range of quantitatively analysis for 12 solvents was satisfactory with the r values all above 0.99, and the recovery and RSD values were in the range of 78.60%-120.80% and 11.50%-16.94%, respectively. 2) Ethyl alcohol was the main residual solvent in medlar, hawthorn, chrysanthemum, and osmanthus (GH1) extracts. The main residual solvents in the other osmanthus extracts (GH2, GH3) and jasmine extracts were methylcyclopentane, n-hexane, isohexane and cyclohexane.

In order to investigate the characteristics of heat-not-burn tobacco products, two heat-not-burn products, A and B, were analyzed in terms of cigarette structure, tobacco material and the release and composition of tobacco smoke. The results showed that: 1) Both A and B tobacco rods consisted of three main parts, namely a heat source, a smoke generation section and a smoke condensation unit. 2) The smoke generating tobacco material in the two products was reconstituted tobacco with considerable glycerol. The total nicotine content in reconstituted tobacco was much lower than that in tobacco leaves for traditional cigarettes, and the form of nicotine was free base nicotine. The reconstituted tobacco in the smoke condensation unit of product A was flavored more than that in the smoke generation section. Various phenolic flavors with smoky aroma note were added in the reconstituted tobacco of product B. 3) The highest heating temperature of product A was above 500 ℃, which caused the combustion of a part of the reconstituted tobacco. However, the heating temperature of product B was about 300 ℃, which was below the ignition point of the reconstituted tobacco. 4) The tar delivery of the two products was significantly lower than that of traditional cigarettes. Large amounts of glycerol esters were detected in the smoke of product A. The contents of moisture and pyrolysis components of saccharide were higher in the smoke of product B.

为考察丙二醇对烟叶加热非燃烧状态下烟气释放的影响,采用差示扫描量热法(DSC)和热失重法(TGA)分析了不同丙二醇添加量烟丝样品的热性能;在200～400℃下,利用实验室加热装置对各样品进行了加热,分析了烟气粒相物、烟碱、水分和焦油释放量.结果表明:添加丙二醇与添加甘油对烟丝热性能的影响虽总体趋势一致,但也存在一定差异;烟气粒相物和焦油释放量均随丙二醇添加量的增加呈增大趋势,添加丙二醇能够显著增加烟气水分释放量,但对烟碱释放量无明显影响;添加丙二醇烟丝样品与添加甘油烟丝样品相比,烟气水分释放量较大,烟气烟碱释放较小,在较低加热温度下的烟气粒相物和焦油释放量较高.

为考察烟叶原料加热状态下的热失重及燃烧特性,采用热失重分析(TG)和差示扫描量热分析(DSC)技术分析了不同类型、不同部位和不同产地烟叶原料的热失重特性和燃烧特性.结果表明:①提高升温速率不改变烟叶的热失重特性,但可加快烟叶的质量损失,有利于烟气的快速释放;②烤烟、白肋烟和香料烟的热失重特性具有明显差异,烤烟和香料烟存在4个热失重阶段,白肋烟只存在3个热失重阶段,其中烤烟和香料烟产生烟气和香味物质主要在第2和第3热失重阶段,白肋烟主要在第2热失重阶段,并且烤烟和香料烟相应的失重率高于白肋烟;③各烟叶均存在挥发物燃烧阶段(200 ～400℃)和炭化物燃烧阶段(400～600℃),并分别对应于各烟叶的后两个失重阶段;④烤烟两个燃烧阶段的着火温度分别在250～280℃和420 ～460℃之间,白肋烟和香料烟均分别在230 ～240℃和410 ～ 420℃之间.

In order to investigate the release characteristics of aroma components in tobacco aerosol under heating, seven tobacco samples, including flue-cured tobacco (B2F, C3F, X2F), oriental tobacco (B1, B2) and burley tobacco (B2F, C3F) were heated by an experimental equipment between 200 ℃-500 ℃, and the aroma components in particle phase matters of tobacco aerosol were analyzed by GC/MS. The results indicated that: 1) The total release of aroma components and the release of aldehydes, ketones, nitrogen containing compounds and aliphatic hydrocarbons significantly increased with the rise of heating temperature; however, they basically kept unchanged when heating temperature ≥400 ℃ . 2) The release of organic acids, furans and pyrans increased first and then decreased with the rise of heating temperature, that of organic acids peaked at 400 ℃, as did that of furans and pyrans at 350 ℃. 3) The release of phenols and aromatic hydrocarbons increased with the rise of heating temperature, which was at a very low level below 300 ℃, while sharply increased beyond 300 ℃; when temperature was higher than 400 ℃, the increase rates slowed down. 4) The release of aldehydes, ketones, furans and pyrans per unit tar was obviously higher and that of phenols and aromatic hydrocarbons per unit tar was much lower below 350 ℃, however the later remarkably increased beyond 350 ℃. 5) The releasecharacteristics of aroma components in tobacco aerosol under heating were influenced by tobacco type greatly, while the effects of stalk position were slight.

To investigate the effects of blend glycerol on the volatile and semi-volatile components in particulate matter of smoke of cut tobacco under low-temperature heating, cut tobacco sample were added with glycerol at different mass levels (0-50%) and heated by an experimental heating device at 300 ℃. The particulate matter of smoke was trapped, and the volatile and semi-volatile components in the smoke were analyzed with GC/MS. The results showed that: 1) Glycerol increased the amount of volatile and semi-volatile components in smoke, however no obvious variation on total amount of volatile and semi-volatile components was observed at the glycerol addition rate of 5%-50%. 2) The released amount of furfural, 2,3-dihydro-3,5-dihydroxy-6-methyl-4H-pyran-4-one and 5-hydroxymethylfurfural was relatively high, which increased first and then decreased with the increase of glycerol. 3) The amounts of megastigmatrienone and neophytadiene transferred increased with the increase of glycerol. 4) Comparing with the control, glyceride was detectable in the smoke of cut tobacco added with glycerol, and its yield raised with the the increase of glycerol. Adding glycerol to cut tobacco enhances the release of volatile and semi-volatile components in the particulate matter of tobacco smoke, though the influences on different components differ.

采用酸水解法和氨基酸自动分析仪测定了茉莉浸膏、杭白菊浸膏、桂花浸膏、酒花浸膏、鸢尾浸膏、树兰花浸膏、枫槭浸膏和树苔浸膏共8类天然食用香料浸膏(共22个样品)中16种氨基酸的含量,如天冬氨酸(Asp)、苏氨酸(Thr)、丝氨酸(Ser)等.研究结果表明,除了茉莉浸膏、酒花浸膏、爱普鸢尾浸膏中未检测到氨基酸外,其他浸膏都含有氨基酸,种类基本相同,但氨基酸的总量均偏低,在5.29 ～ 833.54mg/100g之间;杭白菊浸膏中氨基酸的平均总量最高769.13mg/100g,其中拓普杭白菊浸膏氨基酸总量最高,为833.54mg/100g;树兰花浸膏中氨基酸平均总量最少6.135mg/100g,其中烟草树兰花浸膏中氨基酸总量最少,为5.29mg/100g.单因素方差分析结果表明,不同浸膏中氨基酸的含量具有显著性差异;聚类分析结果表明,所测浸膏主要分为两大类,第一大类包括树兰花浸膏、桂花浸膏、枫槭浸膏、树苔浸膏,第二大类是杭白菊浸膏.

Objective To investigate the volatiles in the thermal reaction flavoring made by tobacco enzymatic hydrolysate.Methods The volatiles were extracted by solid-phase micro extraction (SPME) and simultaneous distillation extraction (SDE), and analyzed by gas chromatography-mass spectrometry (GC-MS). The Maillard reaction solution reacted by the glycine and xylose, was used to be the contrast solution.Results A total of 34 volatile compounds were identified in the thermal reaction flavoring made by tobacco enzymatic hydrolysate, including 20 heterocyclics, 4 acids, 3 ketones, 3 alcohols, 2 aldehydes, 1 phenolic and 1 hydrocarbon compounds. The relative content of heterocyclics was the highest. The relative content of furfural was the highest extracted by SDE (32.483%, 4.799μg/g). A total of 11 volatiles were identified in the contrast solution of Maillard reaction, including 7 heterocyclics, 1 acids, 1 aldehydes, 1 phenolic and 1 hydrocarbon compounds.Conclusion More volatiles, especially the heterocyclic compounds, are generated during the preparation of the thermal reaction flavoring of tobacco, which having a major effect on tobacco flavor modification and also being an important component of cigarette flavor.

In order to assess the effects of ethyl butyrate addition on cigarette smoke, ethyl butyrate was pyrolyzed under conditions simulated cigarette combustion. Cigarette samples added with different rates of ethyl butyrate were prepared, and the deliveries of seven harmful components, including carbon monoxide, hydrogen cyanide, NNK, B[a]P, crotonaldehyde, phenol and ammonia, in mainstream cigarette smoke were determined, the bacterial mutagenicity, in vitro cytotoxicity and micronucleus testing of smoke particulate matter were conducted separately. The results showed that: 1) The pyrolysis behavior of ethyl butyrate mainly was intact transfer under simulated cigarette combustion conditions. 2) Comparing with the control cigarettes, the deliveries of the seven harmful components in mainstream smoke of tested cigarettes did not increase significantly. 3) The results of bacterial mutagenicity, in vitro cytotoxicity and micronucleus assays of smoke particulate matter did not change significantly after ethyl butyrate addition.

In order to quantitatively characterize the micro-porous structure of different kind tobacco leaves, the specific surface area and porosity of flue-cured, burley and oriental tobacco leaves were measured by N2-adsorption-desorption-method followed the pretreatment of immersing in ethanol. Meantime, the surface morphology of tobacco samples was observed by a scanning electron microscope (SEM). The results showed that: all the samples possessed obvious characters of porous medium, i.e. larger specific surface area and smaller pore volume; the porosity of oriental tobacco sample was 2.60%, that of flue-cured and burley tobacco samples was 4.78% and 10.73%, respectively; with a higher proportion of pore in leaf, burley tobacco leaf was open in structure; while oriental leaf was relatively close, and flue-cured tobacco leaf was in-between. The pore distribution characters and pore volume of samples agreed with the observation by scanning electron microscope.