Cigar aging plays a critical role in enhancing flavor complexity and overall quality of cigar. In this study, an untargeted metabolomics method based on headspace solid-phase microextraction coupled with gas chromatography–mass spectrometry (HS-SPME-GC-MS) was used to comprehensively profile volatile compounds and track their dynamic changes during aging. A total of 1,836 volatile compounds were identified, primarily comprising heterocyclics, terpenoids, ketones, and esters. Multivariate analyses, including principal component analysis (PCA) and orthogonal partial least squares discriminant analysis (OPLS-DA), segmented the aging process into four distinct stages, with most differential metabolites showing upregulated trends. Notably, terpenoids exhibited substantial increases in both diversity and abundance. KEGG pathway enrichment analysis highlighted significant involvement of sesquiterpenoid and triterpenoid biosynthesis pathways in cigar aging process. Analysis based on relative odor activity values (rOAV) indicated a progressive enhancement of fruity, floral, honey, woody, and sweet notes, while coffee, roasted, hay, burnt, and spicy aromas declined over time. By integrating rOAV data with K-means clustering analysis, 21 key aroma-active compounds were identified to be closely associated with the aroma changes during aging, including 14 consistently upregulated compounds (e.g., (E)-β-damascone, δ-cadinene) and 7 downregulated ones (e.g., 2-ethyl-3,5-dimethylpyrazine, 3-octen-2-one). These findings provide new insights into the metabolic basis of cigar aging and offer a scientific foundation for optimizing industrial aging processes.

Air-curing is a critical process in the production of cigar tobacco leaves. This process involves the vital degradation and transformation of macromolecular substances into micromolecular chemical compounds. In this study, three different varieties of tobacco leaves harvested from the Wuzhishan and Danzhou areas of Hainan, China were used as materials. Liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) was employed to investigate the chemical changes before and after air-curing in the metabolites. Metabolic analysis revealed significant stepwise alterations in the tobacco leaf metabolome during the air-curing process. A total of 172 differential metabolites were identified as significant contributors in the biosynthesis pathways of flavonoids, flavone, flavonol, and other secondary metabolites, among the total analyzed 1841 metabolites obtained from the tobacco leaves. Notably, the contents of flavonoid metabolites, including kaempferol, rutin, chlorogenic acid, and quercetin, exhibited a significant decrease throughout the air-curing period. Correlation analysis indicated a strong association between the biosynthesis of flavonoids and the contents of chlorogenic acid and kaempferol, suggesting their role in regulation the formation of yellow and brown colors in tobacco leaves. These findings provide valuable insights for future investigations into the quality, commercial value, and chemical properties of cigar tobacco.

[Objective] This study aims to identify the volatile aroma components of cigars and comparatively analyze the difference of the volatile aroma components of different cigars. [Methods] Two analytical detection techniques,namely static headspace-gas chromatography-mass spectrometry（SHS-GC-MS） and gas chromatographic-ion migration mass spectrometry（GC-IMS） were used to detect the volatile aromatic components of Great Wall No.2 and Monte No.4 cigars. Principal component analysis（PCA） and partial least squares discriminant analysis（PLS-DA） were carried out to analyze the difference in main aromatic components of the two cigars.[Results]（1） From the point of smell, the main aromas of the two cigars were dried smoke characteristic aroma and honey-like sweetness..Monte No.4 had more floral, woody and cocoa aromas, but Great Wall No.2 had more sweet and paste aromas, with slightly fruity sweetness and a thicker, more intense aroma.（2） By SHS-GC-MS, 18 volatile aromatic components were identified from Great Wall No.2 cigar and 30 from Monte No.4 cigar. The contents of compositions（Isoborneol, Isobornyl acetate, α-Cedrene, Thujopsene）of Monte No.4were higher than those of Great Wall No.2. However, 3, 5-dimethylphenol and 6-methyl-5-heptene-2-one were only identified in Great Wall No. 2.（3） A total of 47 compounds were identified by GC-IMS in the smoke of the two cigars, including 3 acids, 4 esters, 12 ketones, 10 aldehydes, 11 alcohols, 2 heterocycles and 5 alkenes. PCA and PLS-DA were conducted to analyze the characteristic aromatic smoke components of the two cigars. With variable importance in projection（VIP）＞ 1.0 as the standard, the main different components were cyclohexanone, 2, 3-butanedione, 2-pentanone, benzaldehyde, trans-2-pentenal dimer and dipentene. [Conclusion] Through combination of SHS-GC-MS and GC-IMS, it is possible to detect more volatile aromatic components of the two cigars, based on which the difference analysis of different cigars can be realized by aroma evaluation and statistical analysis.

The quality of fermented plant products is closely related to microbial metabolism. Here, the associations of bacterial communities, metabolites, and functional genes were explored using multi-omics techniques based on plant leaf fermentation systems. The results showed significant changes in the structure of the microbial community, with a significant decrease in Firmicutes and a significant increase in Proteobacteria. In addition, the concentration of metabolites with antibacterial, antioxidant and aroma properties increased significantly, enhancing the quality of the fermented plant leaves. Integrated macrogenomic and metabolomic analyses indicated that amino acid metabolism could be key metabolic pathway affecting fermentation quality. Actinobacteria, Proteobacteria, Firmicutes were actively involved in tyrosine metabolism (ko00350) and phenylalanine metabolism (ko00360), and are presumed to be the major groups responsible for synthesizing growth and flavor compounds. This study emphasized the important role of microorganisms in the changes of metabolites during the fermentation of plant leaves.

[Background] Tobacco-specific nitrosamines （TSNAs） are produced by the nitrosation of tobacco alkaloids with nitrogen oxides during the processing of tobacco， especially during the modulation and fermentation stages. [Objective] To mine the microorganisms that can tolerate high-temperature fermentation of cigar tobacco leaves and reduce the accumulation of TSNAs. [Methods] We examined the high-temperature tolerance， nitrite degradation， and nitrite tolerance of the bacterial strains derived from cigar tobacco leaves that could efficiently degrade nitrite and tolerate high concentrations of nitrite at 50 °C. A efficient strain was then selected and used for a 35-day high-temperature fermentation of cigar tobacco leaves. We determined the levels of nitrite， TSNAs， conventional chemical components， and neutral aromatic components before and after fermentation to analyze the effects of the strain on TSNAs and tobacco quality during the fermentation process. [Results] Three bacterial strains capable of degrading nitrite at 50 ℃ were isolated and identified， which were Bacillus mojavensis NY7， B. halotolerans NY8， and B. subtilis NY9. Among them， B. halotolerans NY8 exhibited the strongest nitrite-degrading capacity. The high-temperature fermentation of cigar tobacco leaves with NY8 reduced nitrite by 96.86% and TSNAs by 67.14%. Moreover， the nicotine reduction caused by the inoculation of NY8 was significant higher than that of the control group， and the total neutral aromatic components （except neophytadiene） were slightly increased. [Conclusion] The isolated strains are suitable for high-temperature fermentation of cigar tobacco leaves and demonstrate high efficiency in degrading nitrite and reducing the accumulation of TSNAs. The findings provide inspiration for reducing the harm of cigar tobacco leaves.

为明确雪茄烟叶适宜的田间成熟度和晾制方式,本研究分析了不同成熟度雪茄烟叶在不同晾房内晾制后物理特性、 化学成分及中性香气物质的变化.结果表明,随着成熟度增加,叶质重、 厚度、 平衡含水量、总糖、 还原糖、 总氮、 烟碱、 钾、 氯、 新植二烯等减少;拉力、 淀粉、 类胡萝卜素类降解产物、 西柏烷类降解产物、 苯丙氨酸类降解产物、 美拉德反应产物等增加.新式晾房相较于传统晾房,烟叶叶质重、 厚度、 总糖、淀粉、 烟碱、 新植二烯等较低;拉力、 钾、 氯、 类胡萝卜素类降解产物、 西柏烷类降解产物、 苯丙氨酸类降解产物、 美拉德反应产物等较高.本研究表明,适当提高田间成熟度,以及采用密闭式晾房进行晾制,可以使雪茄烟叶物理特性改善、 化学成分协调、 香气物质丰富.

In order to study the properties of Konjac glucomannan (KGM)/Gum arabic (GA) composite hydrosol and improve its application performance in food industry, the rheological properties and microstructure of KGM/GA composite hydrosol with different proportions were studied by rheometer, FT-IR, XRD and SEM. The rheological properties and structural characterization of KGM/GA composite hydrosol with different mixing ratio were discussed. The results showed that KGM and GA had a good compatibility, and they could play a synergistic role in a certain mixing ratio. GA could improve the rheology and transparency of KGM, and KGM can improve the viscoelasticity and stability of GA. KGM and GA could promote mutual cross-linking through the increase of hydrogen bonds and the decrease of acetyl groups, strengthen the intermolecular force of the composite hydrosol system and form a uniform and regular structure. When KGM:GA was 5:5(w/w), the KGM/GA composite hydrosol with most excellent comprehensive properties was obtained. Compared with KGM single system, the transparency of the sample increased by 65.82% and the crystallinity was enhanced by 14.57%. And the sample had moderate viscosity, high stability and good viscoelasticity, it was expected to provide some theoretical reference for the development of food adhesives and dietary fiber drinks.

[目的]分析雪茄烟叶发酵过程中颜色变化与主要含氮化合物(总氮、烟碱、蛋白质、氨基酸、硝酸盐、亚硝酸盐、叶绿素a和叶绿素b)及评吸质量的关系,为提升雪茄烟叶发酵品质提供参考依据.[方法]以德雪1号上部叶为试验材料,采用人工堆积法进行发酵,测定发酵过程中雪茄烟叶颜色、主要含氮化合物及评吸质量的变化,探究烟叶颜色变化与主要含氮化合物、评吸质量的关系并建立动态变化预测方程.[结果]雪茄烟叶发酵过程中总氮、烟碱、蛋白质、氨基酸、叶绿素a、叶绿素b含量与颜色参数L*、a*、b*、C值均呈缓慢降低的变化趋势,发酵0～10 d雪茄烟叶含氮化合物降解速率较快,发酵25～30 d差异不显著(P>0.05),发酵30 d时,总氮、蛋白质、烟碱、氨基酸、叶绿素a和叶绿素b含量分别降解18.8％、23.5％、42.5％、31.8％、42.2％和41.4％,L*、a*、b*和C值分别为30.245、8.305、14.350和16.580.硝酸盐、亚硝酸盐含量和H0值呈先升高后降低的变化趋势,△E值呈缓慢上升的变化趋势,发酵30 d时,硝酸盐含量、亚硝酸盐含量、H0和△E值分别为5.78 mg/g、21.11μg/g、30.060和62.303.发酵25 d时烟叶评吸质量较好,雪茄烟风格彰显,烟叶香气透发,烟气醇和感、饱满度和干净度明显提升,杂气和刺激性明显降低,余味舒适,烟气平衡感较好,各评吸指标均优于未发酵烟叶.相关分析结果表明,发酵过程中雪茄烟叶颜色参数与主要含氮化合物、评吸质量的相关性达显著(P<0.05)或极显著(P<0.01)水平.回归分析结果表明,总氮、蛋白质、氨基酸、叶绿素a和叶绿素b对发酵过程中雪茄烟叶颜色变化有直接影响,评吸质量与颜色参数关系密切.[结论]发酵过程中颜色参数与主要含氮化合物及评吸质量关系密切,通过建立发酵过程中评吸质量变化模型来提高雪茄烟叶发酵过程中的可控性,获得评吸质量较好的雪茄烟叶.

The quality of fermented plant products is closely related to microbial metabolism. Here, the associations of bacterial communities, metabolites, and functional genes were explored using multi-omics techniques based on plant leaf fermentation systems. The results showed significant changes in the structure of the microbial community, with a significant decrease in Firmicutes and a significant increase in Proteobacteria. In addition, the concentration of metabolites with antibacterial, antioxidant and aroma properties increased significantly, enhancing the quality of the fermented plant leaves. Integrated macrogenomic and metabolomic analyses indicated that amino acid metabolism could be key metabolic pathway affecting fermentation quality. Actinobacteria, Proteobacteria, Firmicutes were actively involved in tyrosine metabolism (ko00350) and phenylalanine metabolism (ko00360), and are presumed to be the major groups responsible for synthesizing growth and flavor compounds. This study highlights the important role of microorganisms in plant leaf fermentation, and provides a new perspective for the screening of functional microorganisms that degrade nitrogen-containing compounds.

Revealing community assembly and their impacts on ecosystem service is a core issue in microbial ecology. However, what ecological factors play dominant roles in phyllosphere fungal community assembly and how they link to crop quality are largely unknown. Here, we applied internal transcriptional spacer high-throughput sequencing to investigate foliar fungal community assembly across three cultivars of a Solanaceae crop (tobacco) and two planting regions with different climatic conditions. Network analyses were used to reveal the pattern in foliar fungal co-occurrence, and phylogenetic null model analysis was used to elucidate the ecological assembly of foliar fungal communities. We found that the sensory quality of crop leaves and the composition of foliar fungal community varied significantly across planting regions and cultivars. In Guangcun (GC), a region with relatively high humidity and low precipitation, there was a higher diversity and more unique fungal species than the region of Wuzhishan (WZS). Further, we found that the association network of foliar fungal communities in GC was more complex than that in WZS, and the network properties were closely related to the sensory quality of crop. Finally, the results of the phylogenetic analyses show that the stochastic processes played important roles in the foliar fungal community assembly, and their relative importance was significantly correlated with the sensory quality of crop leaves, which implies that ecological assembly processes could affect crop quality. Taken together, our results highlight that climatic conditions, and plant cultivars play key roles in the assembly of foliar fungal communities and crop quality, which enhances our understanding of the connections between the phyllosphere microbiome and ecosystem services, especially in agricultural production.

为便于统计分析和研究雪茄产品的生产发展状况,依据制作方式和产品结构将国产雪茄分为手制雪茄、半手制雪茄、机制雪茄和卷烟型雪茄四种类型,并遵循术语一致性原则,突出雪茄特征描述用语的规范性和严谨性,首次探讨性地提出雪茄烟支属性采用茄衣原料种类、茄套原料种类、茄芯原料形态、茄衣卷制方式、茄胚成型方式和雪茄接嘴种类等6种特征进行表述,并通过对近15年国产雪茄生产发展数据进行统计分析的应用实例阐明了雪茄分类和属性特征描述的应用方法.文中还对国内在雪茄学术研究和实际应用中长期存在的术语认知问题进行了讨论辨析,并就国产雪茄发展中的短板以及技术研究、标准制订和术语规范化等有关方面提出了一些看法与建议.

[目的]研究不同发酵方法对四川德阳雪茄茄芯烟叶堆积发酵过程中品质因素的影响,为提高国产雪茄烟叶质量提供技术参考.[方法]采集雪茄茄芯烟叶发酵过程中不翻堆(T1)和翻堆(T2)处理烟叶样品,采用多重数据差异显著法对烟叶物理特性、化学成分和中性致香物质动态变化规律进行分析,并评价发酵后烟叶感官质量.[结果]发酵过程中烟堆最高温度为46.5 ℃,发酵至第21 d时T1和T2处理烟堆温度分别为39.5和38.5 ℃,烟叶含水率分别为19.1%和18.7%.发酵过程中烟叶叶质重和叶厚呈下降趋势,发酵至第20 d T2处理叶质重和叶厚显著高于T1处理(P＜0.05,下同);拉力呈先上升后下降的变化趋势,发酵至第10 d T1处理拉力显著高于T2处理.发酵前茄芯烟叶总糖和还原糖含量较低,发酵至第5 d T2处理总糖含量显著高于T1处理;发酵至第20 d,T1处理烟叶氯、总氮和蛋白质含量显著高于T2处理,T2处理烟叶钾含量显著高于T1处理.类胡萝卜素降解产物在发酵第15 d时含量最高,发酵至第20 d,T2处理法尼基丙酮、β-大马酮、巨豆三烯酮2和巨豆三烯酮4含量显著高于T1处理;T2处理棕色化反应产物在发酵第10 d开始显著高于T1处理,发酵至第15 d时糠醇和5-甲基糠醛含量最高;发酵过程中苯丙氨酸转化产物含量呈先升高后降低的变化趋势,发酵至第20 d T2处理苯甲醇、苯乙醇和苯乙醛含量均显著高于T1处理;T2处理烟叶发酵10～20 d的茄酮含量显著高于T1处理,发酵至第15 d时苯甲醇和苯乙醛含量达最大值.发酵20 d后,T2处理烟叶烟气甜感突出,刺激性和杂气明显降低,焦甜香和醇甜香突出,余味舒适,可燃吸指标平衡感优于T1处理.[结论]发酵过程中翻堆处理能提高雪茄茄芯烟叶中性致香物质含量,降低烟叶杂气和刺激性,获得香气和吃味较好的雪茄烟叶.

利用气相色谱质谱联用仪对格蓬油挥发性成分进行分析,共鉴定出81种成分,主要成分分别为β-蒎烯(34.88％)、3-蒈烯(16.48％)、α-蒎烯(12.18％)、2-侧柏烯(5.79％)、δ-杜松烯(3.35％)、月桂烯(3.24％)、α-依兰烯(2.64％),其中烃类物质最多有46种,百分含量为91.65％.

Abstract Microorganisms of plant phyllosphere play an important role in plant health and productivity and are influenced by abiotic and biotic factors. In this study, we investigated the phyllosphere bacterial communities of three cigar tobacco varieties cultivated in Guangcun (GC) and Wuzhishan (WZS), Hainan, China. Metagenomic DNA was extracted from tobacco leaf samples and sequenced by 16S rDNA amplicon sequencing. Our results showed that bacterial communities of cigar tobacco phyllosphere in GC exhibited remarkably higher alpha diversity than that in WZS. There was slight effect of tobacco genotype variations on the alpha diversity in both cultivation sites, and beta diversity and structure of bacterial community were not influenced significantly by the cultivation sites and tobacco varieties. Statistical analyses of species diversity unraveled that the dominant species in bacterial communities of cigar tobacco phyllosphere among all these samples were phylogenetically affiliated to Proteobacteria and Cyanobacteria. At the genus level, the most abundant microorganism was Limnobacter, followed by Brevundimonas, unidentified_Cyanobacteria, and Pseudomonas. Additionally, environmental conditions except for humidity were negatively correlated with the relative abundance of bacterial genera. Further analyses revealed that influence of site‐specific factors on tobacco bacterial community was relatively higher than genotype‐specific factors. In short, this study may contribute to the knowledge base of practical applications of bacterial inoculants for tobacco leaf production.

为了揭示生态环境和基因型对雪茄烟叶际真菌群落结构的影响,本研究采用高通量测序技术分析了2个生态环境(五指山、儋州光村)和3个基因型(M1～M3)对大田成熟期雪茄烟叶际真菌群落结构的影响.研究表明,不同基因型的雪茄烟在不同生态环境条件下叶际真菌的Shannon、Simpson、Chao1和ACE指数存在显著差异,光村生态区的烟叶样本真菌OTU数量是五指山的3.07倍,三个不同基因型的雪茄烟叶中以M.3的OTU数量最高;3大优势菌群门分别是子囊菌门、担子菌门、被孢霉门;3大优势属分别是枝孢属,桑帕氏酵母菌属、尾孢菌属;叶际真菌群落结构受生态环境、基因型以及二者的交互作用的影响,但受生态环境影响最为显著.可知,生态环境是成熟期雪茄烟叶际真菌群落的主要影响因素.

为探究不同采收时间对雪茄烟叶产质量的影响,以德雪3号为材料,通过大田试验和室内试验,研究雪茄烟叶3个采收时间(中部叶、上部叶分别于移栽后70、77d第1次采收,之后每隔10d采收1次,共采3次)下烟叶调制时的含水率、发酵后的物理特性、常规化学成分含量和中性致香物质含量以及经济性状的差异.结果表明,采收越晚,调制期间烟叶失水速率越快;中部叶移栽后80 d采收,发酵后烟叶的拉力、叶厚度等物理性状表现较优,总氮含量较移栽后70 d采收下降0.180个百分点,烟碱含量较移栽后90 d采收升高0.450个百分点,烟叶化学成分协调性较好,且此时烟叶中香气物质总量较移栽后70、90 d采收分别提高17.68％、5.58％;上部叶移栽后87d采收,发酵后烟叶物理性状更优,氮碱比为4.926,烟叶化学成分协调性较好,烟叶香气物质总量较移栽后77、97 d采收分别提高16.23％、1.88％.中部叶移栽后80d采收烟叶产值较移栽后70、90d采收分别提高16.85％、12.10％,上部叶移栽后87 d采收烟叶产值较移栽后77、97d采收分别提高13.57％、16.52％.因此,德雪3号中部叶于移栽后80 d左右采收、上部叶于移栽后87 d左右采收,烟叶物理特性最佳、化学成分协调性最好,香气量足、感官质量较优,产值最高.

因得天独厚的地理优势,美国康涅狄格州的康涅狄格河谷成为了世界上少有的优质雪茄烟叶产地,经过几百年的技术积累与沉淀,康涅狄格州雪茄烟叶因其独特的内在品质和完美的外在品质,成为国际雪茄烟叶市场上的主要原料之一,在各大雪茄品牌中都有使用.文章从雪茄烟叶生产历史、主要产区特点、主栽品种、生产技术以及分级和销售几个方面介绍了美国康涅狄格州雪茄生产的发展概况,以期为中式雪茄原料的发展提供一些参考.

近年来,国内雪茄市场增长迅速,而国产优质雪茄原料的缺乏,极大限制了国产雪茄产业的健康、可持续发展。本文总结了国内雪茄主要产区的生态条件、生产技术和工艺,分析了遮荫和发酵等雪茄生产重要环节的机理。最后展望了国产雪茄原料的技术研究领域的发展方向,以期为今后技术体系的完善和国产雪茄原料质量的提升奠定基础。

简述了类胡萝卜素降解产物在烟叶中的重要作用,并从矿质营养及施肥方法、种植密度、留叶数、采收方式和成熟度等栽培措施以及调制温湿度和方法等方面对影响晾晒烟中类胡萝卜素降解产物含量的因子进行了综述,并对今后的研究内容做了展望.

To investigate suitable aging time for cigar filler used in industrial formulation, the fillers of three main varieties of domestic cigars were compared based on the effects of aging time on the physical properties, chemical components and sensory quality. The results showed that after the three filler varieties were aged at the humidity of 70% ± 5% and temperature of 18-27 ℃ for 21-27 months, their overall quality was improved and maintained relative stability.