Recent years have witnessed major advances in heated tobacco products. However, optimizing the aroma release and smoke generation of these products remains a formidable challenge. Alkali metal salts have emerged as effective catalysts for pyrolysis, demonstrating the dual benefits of enhanced catalytic efficiency and alleviating coke deposition. To effectively illustrate the effect of adding salt on the low-temperature catalytic pyrolysis performance of reconstituted tobacco sheets, thermogravimetric analysis and pyrolysis gas chromatography-mass spectrometry analyses were carried out, and the Flynn-Wall-Ozawa method and the Kissinger method were also applied to calculate reaction kinetics. The addition of the sodium (Na) salt or potassium (K) salt in reconstituted tobacco sheets was observed to significantly decrease the temperature corresponding to the maximum weight loss rate and increase the total weight loss with the range of 100-300 degrees C. Meanwhile, the content of key components in the pyrolysis gas gradually increased, indicating that the ability to catalyze cellulose and lignin pyrolysis improved. The results of dynamic analysis show that the apparent activation energy of reconstituted tobacco sheets decreased by an average of 80.95 or 49.12 kJmol-1 after adding Na or K salt when the conversion rate was 0.1-0.8. The approach reported herein not only exhibits a fundamental advance in the low-temperature pyrolysis of reconstituted tobacco sheets for heated tobacco products but also increases the concentration of pyrolysis gas and aromatic substances.

Cherry-red tobacco has aroused significant interest in both the academic and industrial fields due to its unique aroma style. In order to analyze the aroma characteristics of Cherry-red tobacco and the intrinsic aroma substance basis, the aroma compounds were analyzed by gas chromatography-mass spectrometry (GC-MS), the aroma characteristics were verified by sensory evaluation, and a correlation analysis was further conducted. The sensory evaluation suggested that Cherry-red tobacco was significantly richer in aroma, containing a total of 11 aromas, among which nutty, bean, herbal, and spicy were the characteristic aromas. The analysis of aroma compounds indicated that there were 88 differentiating aroma compounds between Cherry-red tobacco and Yunyan 87. The correlation analysis revealed that the glutinous sweet aroma of Cherry-red tobacco was strongly correlated with phenols, aromatic hydrocarbons, and aldehydes, while the fresh sweet aroma of Yunyan 87 was strongly correlated to ketones and nitriles. There were 24 characteristic aroma substances with strong correlations with the glutinous sweet aroma of Cherry-red tobacco. Furthermore, based on the odor and OAV analysis results, 2-vinylpyridine, 2,6-dimethylpyridine, scopoletin, 4-methylphenol, and eugenol were the key aroma compounds that highlighted the characteristic aroma of Cherry-red tobacco.

The low temperature catalytic pyrolysis performances of heated tobacco sheets by alkali/alkaline earth metal were investigated by TG-FT-IR and Py-GC-MS. Thermogravimetric analysis showed that the maximum weight loss rate temperature of the heated tobacco sheets significantly reduced from 328 degrees C to 292 degrees C catalyzed by alkali metal Na or K catalysts, and the weight loss between 100 and 300 degrees C increased by 48.83% and 40.05% respectively. While alkaline earth metal Mg or Ca catalysts exerted less influence on the maximum weight loss rate temperature and the weight loss between 100 and 300 degrees C reduced slightly. The online infrared absorption band of pyrolysis gas shifted to lower temperature and the concentration of pyrolysis gas increased over Na catalysts, which matched well with TG results. Moreover, the concentration of carbonyl compounds and compounds containing C-O bonds in pyrolysis gas increased significantly. The content of 2-furanmethanol, butyrolactone and megastigmatrienone in pyrolysis gas increased under the assistance of alkali metal Na or K. Model compounds research confirmed that alkali metal could catalyze low temperature pyrolysis of cellulose in heated tobacco sheets. These results demonstrated that the pyrolysis of heated tobacco sheets could be catalyzed by alkali metal catalysts at low temperature, increasing the concentration of pyrolysis gas and aroma substance. This research provided a new idea for the study of aroma and concentration enhancement of heated cigarettes through catalytic technology.

为脱除烟草超临界提取物中的蜡质成分,降低其在卷烟中使用时产生的不良风味,以云南清香型烟叶模块碎片为原料,通过超临界CO2提取、乙醇脱蜡和冷冻离心等工艺,制得云烟净油及其蜡质脱除物;并通过GC-MS分析和感官质量评价,确定了各组分的化学组成及感官作用.结果表明:①该工艺的蜡质脱除率高达99.83％,21种C25～C33的蜡质烷烃得到有效脱除;②烟草超临界提取物经脱蜡后可有效改善卷烟感官作用;③超临界提取物的脱蜡工艺可实现烟草致香成分、烟草甾醇和天然维生素E的有效富集.该乙醇脱蜡方法可用于烟草超临界提取物的精制化.

本文采用Ce(OTf)3和Sc(OTf)3复合催化4-甲基-7-氨基苯并吡喃酮、芳香醛和二茂铁基乙炔发生Povarov三组分反应(Povarov-3CR),高效合成了 15种已知二茂铁基吡喃酮并喹啉化合物,产率为40.0％～66.8％;采用1H NMR、13C NMR和HR-MS(ESI)表征产物分子结构,通过抑制HO·和还原型谷胱甘肽自由基(GS·)引发DNA氧化反应测试比较化合物抗氧化活性,探究取代基种类、位置和数目对二茂铁基吡喃酮并喹啉抗氧化性能的影响.结果表明:抑制HO·引发DNA氧化反应测试显示,15个目标化合物相对空白硫代巴比妥酸活性物质吸光度百分数(TBARS百分数)为36.6％～83.3％;抑制GS·引发DNA氧化反应体系测试显示,15个目标化合物TBARS百分数达22.9％～67.2％;在分子中引入推电子基团(-N(CH3)2、-OCH3和-OH)均能提升目标化合物的抗氧化能力,而吸电子基团(-Cl)有降低抗氧化能力作用;二茂铁基吡喃酮并喹啉化合物的抗氧化性能优于二茂铁基喹啉化合物,是一类潜在的强抗氧化剂.

Tobacco genetic purity is crucial to maintain the quality of cigarette products in the tobacco industry. To reduce the difficulties in the discrimination of large number of tobacco cultivars in production practice, we developed a two-step identification strategy by using SCAR and RAPD markers. A total of 53 tobacco cultivars were examined in the study. Initially, all the selected cultivars were divided into four groups, each group consisted of seven to seventeen tobacco cultivars based on difference in phenotypes identified by the SCAR markers S4 and S8. Later, in each group, each tobacco cultivar was identified using RAPD fingerprinting by using one to four polymorphic primers, which were selected from 200 random primers. The results showed that all 53 tobacco cultivars could be effectively distinguished by using only two SCAR and seven RAPD markers. The two-step fingerprinting strategy could be used as a convenient and cost-effective tool to discriminate large numbers of tobacco cultivars for production planning in the tobacco industry.

采用分子络合法进行试验,制备了西瓜香精-α-环糊精微胶囊,并进行仪器表征,进一步验证了西瓜香精-α-环糊精微胶囊具稳定结构、高热稳定性,并有效延缓西瓜香精挥发.最佳工艺条件为α-环糊精水中质量浓度为20 g/L,芯壁比为1:3,西瓜香精与吐温20的比例为2:1,反应时间为2.0 h,反应温度为60℃.在此条件下制备的西瓜香精-α-环糊精微胶囊平均粒径较小(201.2 nm),微胶囊包封率为80.4％.红外光谱分析、X射线衍射表明α-环糊精与西瓜香精形成了稳定的包埋结构,热重分析证明微胶囊增加了西瓜香精的热稳定性,电子鼻分析说明微胶囊具有良好的释放性能.由此证明制备的西瓜香精-α-环糊精微胶囊包埋效果好、稳定性强、缓释性能好.

This paper describes the regioselective C-3 sulfenylation ofN-sulfonyl protected 7-azaindoles with sulfonyl chlorides. In this transformation, dual roles of TBAI serving as both promoter and desulfonylation reagent have been demonstrated. The reaction proceeded smoothly under simple conditions to afford 3-thio-7-azaindoles in moderate to good yields with broad substrate scopes. This protocol refrains from using transition-metal catalysts, strong oxidants or bases, and shows its practical synthetic value in organic synthesis.

针对现有卷烟感官品质评价方式的评价结果差异不明显和变化趋势不明确的问题,建立了一种新的烟草感官品质对比评价方法:采用专家咨询法并结合实际评吸经验,根据消费者的关注程度对优雅度、满足感、舒适感和轻松感各感官品质评价指标赋予权重,利用数理统计方法对各评吸人员的评价结果进行计算,得出卷烟各感官品质评价指标小项和总体得分,并根据各项得分判定实验样品间感官品质差异程度和变化方向.可行性验证结果表明:该方法即使在感官品质变化较小时,也能够较好地从分值上进行区分;其既能反映整体感官品质的差异程度,又能反映总体或单个感官品质评价指标的变化趋势,且感官品质差异性的区分度也较明显,可应用于卷烟制品的研发和品质控制.

为建立快速鉴定烟草品种的方法,利用RAPD分子标记方法对13个烟草品种进行鉴定,分别应用二元表法和人工绘制品种树图(Manual cultivar identification diagram,MCID)法2种分析方法对烟草品种DNA指纹图进行分析.结果表明:从150条特异性引物中共筛选出4条稳定性好、特异性高的随机引物,得到4张DNA指纹图,利用2种分析方法对指纹图分析后成功得到13个品种的分子ID,并构建出13个烟草品种的MCID.研究发现,2种分析方法均可有效鉴定烟草品种,其中,MCID法的直观性和可加性优于二元表法,操作性更强,当供试品种较多时MCID法更简单实用,可用于大量烟草品种的快速鉴定.

为开发促进烟叶品质改善的新型生物制剂,研究了鞘氨醇单胞菌Sphingomonas sp.XP对降解复烤后烟叶中多酚类的作用,优化了发酵条件,并对发酵后烟叶中主要多酚物质、常规化学成分和感官质量进行了评价.结果表明:①在菌液接种量15wt％,相对湿度65％,30℃条件下发酵30 d,烟叶中多酚降解效果最佳;②菌株XP发酵处理对烟叶中绿原酸和芸香苷具有显著降解作用(P＜0.05),而对于莨菪亭的降解没有显著作用(P＞0.05);③经鞘氨醇单胞菌发酵处理后烟叶淀粉含量显著降低(P＜0.05);总糖、还原糖含量显著增加(P＜0.05);总氮、总植物碱和蛋白质含量没有显著变化(P＞0.05);感官质量提高.

To effectively identify the varieties of cured tobacco leaves, the genomic DNA of cured leaves of 11 varieties commonly used was extracted by magnetic bead method. The fingerprint spectra based on SSR markers were constructed by PCR and agarose gel electrophoresis. The results showed that five primer pairs with high polymorphism and stability were selected from 24 SSR primer pairs. The amplified products of the five primer pairs were 100-300 bp in length and clear bands were obtained via 3% agarose gel electrophoresis. On the basis of electrophoregram of the five primer pairs, the fingerprint spectra of the 11 tobacco varieties were constructed, and the flow chart of variety identification was drawn for rapid differentiation of the 11 tobacco varieties. This method is simple, practical and convenient to identify the varieties of cured tobacco leaves.

With 12 varieties of flue-cured tobacco as a template,the conditions for primer concentration and annealing temperature for 6 pairs of SCAR primers were optimized.Multiplex PCR fingerprints and identification routes of 12 flue-cured tobacco varieties were established by multiplex PCR.The results showed that multiplex PCR had the advantages of high efficiency, high speed, time saving and low cost compared with ordinary PCR.Six pairs of SCAR primers had good stability and specific band specificity, which could distinguish 12 flue-cured tobacco varieties accurately.

To improve the effects of cut strip casing, the influences of technical parameters on casing effects were tested and analyzed. The results showed that: 1)The comprehensive quality of strip cutting was better at the compensation steam valve opening of 10%. 2) Via screening by a vibration sieve with 1 mm mesh after strip cutting, the cut strips adhering to casing cylinder wall were obviously reduced, the percentage of broken strands in dried cut strips was lower and the uniformity of casing was better. 3) The coefficient of casing uniformity and the effective utilization rate of casing increased first and then decreased with the increase of HT steam pressure before casing, the moisture content(within a range of 16%-22%)in cut strips, the exhaust fan motor frequency and compensation steam valve opening. 4) The cut strips adhering to casing cylinder wall increased with the rise of HT steam pressure before casing.

In order to make better use of low grade tobacco, a flow extraction system for tobacco was developed. The system was mainly composed of an extraction tank, an extraction solvent recycling unit and an extraction solvent supplying unit. In the recycling unit, extraction solvent was separated from extracts. The supplying unit supplied extraction solvent to the extraction tank for flow extraction. Cut tobacco of low grade was treated by flow extraction and cylinder drying (the control) separately, the results showed that: comparing with the control, the flow extraction reduced the change rate of long strand proportion, nicotine, tar and hazard index by 1.22 percentage points, 40.37%, 33.13% and 25.67%, respectively; while increased potassium by 34.55%. After extraction, the utilization value of cut tobacco was promoted as a whole, more than 43.9 RMB yuan/kg could be saved. The system not only improves the utilization value of low grade tobacco, it is also helpful to reducing tar and harmful components.

In order to simulate cut tobacco drying in a primary processing line exactly, a laboratory cut tobacco cylinder dryer was designed based on the working principle of thin plate cylinder dryer. The designed dryer was mainly composed of a bracket, a drying cylinder, a frequency conversion drive system, a heating temperature control system and a moisture exhaust system. Cylinder wall temperature was controlled via a heater, a heat insulation layer and an automatic temperature control system; cylinder's rotational speed was regulated by a frequency conversion motor; and the wet air was exhausted through moisture exhaust system. The inlet and outlet of tobacco were combined into one, and the bracket structure was designed so as to facilitate drying cylinder tipping and accelerate tobacco discharging. Taking the cut rags of brand"Gold leaf (Dajinyuan)"as experimental material, three drying devices, laboratory cylinder dryer, electric oven and thin plate cylinder dryer (the control), were compared in terms of physical properties and sensory quality of dried tobacco. The results showed that:1)The filling value of cut strips dried by laboratory cylinder dryer was 4.54 cm3/g and that of the control was 4.62 cm3/g, the elasticity, crimpness and loosening degree of the two were close, and the consistent rate of sensory quality between them reached 68%, which satisfied the requirements of sensory quality consistency for cigarettes. 2) The filling value of cut strips dried by electric oven was 4.02 cm3/g, and the sensory quality of the same was slightly worse. 3) The performance of laboratory cylinder dryer was close to that of thin plate cylinder dryer.

Using the single factor and orthogonal experiments with the flue-cured tobacco varieties of zhongyan100 as raw material and two SCAR primers to study the multiple PCR reaction system in the inter-action between the main ingredients of flue-cured tobacco leaves,the best suitable multiple PCR reaction system was established for roast tobacco including DNA template 45 ng,Mg2 + concentration 2. 50 mmol/L,dNTP concentration 0. 40 mmol/ L and Taq enzyme dosage 4. 00 U on the 20 μL system. The stripe of the system is clear and it can shorten the identification time,laying a foundation for using multiple PCR technology to identify flue-cured tobacco varieties.

In order to understand the effect of cigarette quality on different cigarette lap adhesive glue quantity, three different cigarette lap adhesive glue quantity have been tested in the same condition. The results showed that:1)the different cigarette lap adhesive glue quantity is influential of the sensory quality of cigarette, sizing amount is smaller, the better the sensory quality of cigarette. 2) with the change of cigarette lap adhesive glue quantity, physical quality and chemical components of mainstream smoke of cigarette was not obvious.

The physical indexes and chemical constituents of microwave expanded bar-shaped stem shreds were determined and analyzed, and the effects of its application into cigarette were evaluated. The results showed that: 1) The filling value of microwave expanded bar-shaped stem shreds was similar to that of cut stem, though its size was smaller, its size distribution was more uniform. 2) The contents of total sugar and reducing sugar were higher in microwave expanded bar-shaped stem shreds. 3) With the increase of blending proportion of microwave expanded bar-shaped stem shreds, the individual weight, puff number and hot collapse of cigarette and the deliveries of tar, nicotine and CO in mainstream cigarette smoke decreased; while the draw resistance, tobacco loss from cigarette end, dust content and free combustion rate of cigarette increased; and the ash integration of cigarette improved. 4) At the same blending proportion, comparing with cut stem, the cigarette containing microwave expanded bar-shaped stem shreds showed higher individual weight, draw resistance, hardness, tobacco loss from cigarette end and dust content; lower standard deviation of individual weight and higher standard deviation of draw resistance; lower puff number and lower deliveries of tar, nicotine and CO in mainstream smoke; faster free combustion rate; smaller hot collapse and better ash integration, and significantly improved sensory quality.