Neutral Aroma Components Research Articles

Zonal distribution of neutral aroma components in flue-cured tobacco leaves

To understand the regional distributions of neutral aroma components (NACs) of interest in flue-cured tobacco (Nicotiana tabacum L.), samples from a single cured leaf lamina were taken at 48 distinct points with the help of a thin transparent plastic board. We investigated 28 NACs belonging to five categories, namely aromatic amino acid cleavage substances (ACS), cembratriendid alkyl degrading products (CADP), carotenoid degradation products (CDP), chlorophyll degradation products (CDPS), and Maillard reaction components (MRC), by comprehensive two-dimensional gas chromatography (GC × GC–TOFMS) analysis. Geostatistical tools and statistical software were subsequently used to analyze the NAC contents. The results showed that the contents of all the five categories had high levels of significance at 0.01. The nugget effect value of the different NACs exceeded 75%, and the Kriging interpolation map showed a continuous spatial structure. Based on the NAC contents, it was clear that only one principal component had a characteristic value greater than 1 (at 4.9), which accounted for 87.81% of the total variation. With the help of the Management Zone Analyst software, the NACs of a single tobacco leaf were accurately divided into six zones after k-means cluster verification. Overall, these results provide valuable information that will improve the use of tobacco leaves in tobacco threshing and redrying. Moreover, the results suggest the approach described herein can also be used for analyzing the distributions of chemicals in leaves with structures similar to tobacco.

Capturing tobacco specific N-nitrosamines (TSNA) in industrial tobacco extract solution by ZnO modified activated carbon

Adsorption of tobacco specific N-nitrosamines (TSNA) in industrial tobacco extract solution by ZnO modified activated carbon (AC) was deeply studied in order to discern the liquid adsorption. ZnO was coated on AC by wet impregnation and characterized with X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and nitrogen-adsorption–desorption to evaluate its modification on the structure of sorbent. Apart from common tobacco extract solution, the industrial extract solution with a higher TSNA content and viscosity was used to assess the performance of ZnO modified AC with monitoring of LC–MS/MS technique. The influence of TSNA concentration, S/L ratio, adsorption time and recycle index was also systemically studied. To explore whether ZnO modification induces some selective adsorptive sites on AC, elution of TSNA from sorbent and the adsorption of main neutral aroma components in tobacco extract solution were performed. About 80% of TSNA could be trapped in the solution and the ZnO/AC sorbent showed a kind of selectivity for 4-methylnitrosamino-1-3-pyridyl-1-butanone (NNK).

Effect of ecological environment on upper stalk leaves quality and neutral aroma components of burley tobacco

Effect of ecological environment on upper stalk leaves quality and neutral aroma components of burley tobacco

Analysis on the relationship between water-soluble carbohydrate content and neutral aroma ingredients in flue-cured tobacco

Multivariate methods were conducted to determine canonical and simple correlations between the water–soluble carbohydrate(fructose,glucose and sucrose) and the neutral aroma components in flue–cured tobacco.The results indicated that the first canonical correlation between the content of the three tested water–soluble sugars and plastid pigments,browning reaction products,aromatic catabolites aroma components achieved a remarkable level of 1%;the second canonical correlation coefficient of the three neutral aroma components and the first canonical correlation coefficient of cembratriendiol both achieved a remarkable level of 5%.These correlations depended mainly on the correlation between megastigmatrienone 2,megastigmatrienone3,β–dihydrodamascone,6–methyl–5–hepten–2–one,5–methyl furfural,2–acetyl furan,4–vinyl–2–methoxyphenol,6–methyl–5–hepten–2–ol and the water–soluble carbohydrate.The water–soluble carbohydrate was negatively correlated with plastid pigments,aromatic catabolites and cembratriendiol,positively correlated with browning reaction products.Water–soluble reducing sugar showed close relationship with cembratriendiol and aroma components from aromatic catabolites,their coordination could be conducive to improving the quality of flue–cured tobacco.

Analytical method of free and conjugated neutral aroma components in tobacco by solvent extraction coupled with comprehensive two-dimensional gas chromatography–time-of-flight mass spectrometry

A reliable and simple method for quantitative analysis of free and conjugated neutral aroma components (including aldehydes, ketones, alcohols, esters and alkenes) in tobacco using comprehensive two-dimensional gas chromatography–time-of-flight mass spectrometry (GC×GC–TOFMS) is described. Simple solvent extraction using methyl tert-butyl ether (MTBE) ensured extraction of the neutral aroma components in their free form. The components present as conjugates were isolated using MTBE extraction following acid-catalysed hydrolysis. The GC×GC–TOFMS analysis was performed to comprehensively identify different forms of neutral aroma components in tobacco. Compared with the conventional methods, our method not only simplified the process but also saved time and solvent. It also exhibited higher selectivity and sensitivity and demonstrated the following results: the limit of detection of the neutral aroma components varied from 0.006μg/g for 2-acetylfuran to 0.133μg/g for 5-(hydroxymethyl)-2-furfural, the relative standard deviations were from 0.5% to 6.8% and the recovery ranged from 82.4% to 118.2%. The optimized method was successfully employed to analyse real tobacco samples. Eighty-three neutral aroma components of interest were identified.

Effect of fan speed changes on neutral aroma components of flue-cured tobacco during bulk curing

Effects of different fan speed changes on the contents of neutral aroma constituents in flue-cured tobacco leaves during bulk curing period were studied by applying frequency conversion technology.The results showed that total contents of neutral aroma components were higher under the 1 450 r/min of rotation speed than those under the 960 r/min of rotation speed when the temperature was between 42 ℃ and 54 ℃.While they reached the highest under the 1450 r/min of rotation speed when the temperature was between 42 ℃ and 54 ℃ and 720 r/min afterward;in the meanwhile,the contents of carotenoids,aroma aminophenol,maillard reaction products,cemdrenoid and neophytadiene were all higer than those under the 1 450 r/min of rotation speed during the whole process.

Analysis of the neutral aroma component in different leaf positions of flue-cured tobacco

Neutral aroma components in different leaf positions of flue-cured tobacco in Xuchang were comparatively analyzed by a capillary GC equipped with FID and NPD, And GC/MS. The results indicated that: Most aroma components of mature tobacco leaves from eight to twelve increased first and decreased afterwards with the increasing of the leaf position from the 8th up to the 12th leaf and the maximum components was found at the 10th leaf position,such as Dihydro actinidiolide, MegastigmatrienoneⅠ, Farnesalacetone, Benzyl alcohol, Phenylethyl alcohol, 2-Acetylpyrrole, Furfural, Solanone; Various kinds of aroma components in the 10th leaf position were the highest, and Neophytadiene, Farnesalacetone, 2-Acetylpyrrole, Solanone, Dihydro–actinidiolide were obviously higher than those of others; β-Dmascenone, MegastigmatrienoneⅢ, Geranylacetone, 3-Oxo-α-ionol, Benzaldehyde components in the 12th leaf position are obviously higher than the other four leaf positions; Besides the Marillard reaction products and cembrane aroma components, aroma components,neophytadiene, carotenoid degradation products and aromatic amino reaction products components in the 11th leaf position were next to the 10th leaf position. 3- Hydroxy-β-damascone, MegastigmatrienoneⅡin the 8th leaf position were obviously higher than the other four leaf positions.

Relationship of Nicotine and Total Nitrogen Contents with Neutral Aroma Components in Flue-Cured Tobacco in Central Area of Henan Province

The flavor quality of tobacco is highly correlated with nicotine content, while the relationship between aroma components and nicotine content is unknown. The aroma constituents come from different precursors and contribute differently to aroma styles. A total of 27 Flue-cured tobacco samples were collected from full aroma tobacco growing areas to investigate the relation-ship of nicotine and total nitrogen contents with neutral volatile aroma component contents by GC/MS. Results showed that there existed significantly positive quadratic correlation relationship between nicotine, total nitrogen and carotenoid catabolite contents, with the maximum carotenoid catabolites contents at the nicotine content of 3.82%. In the range of nicotine contents from 1.28% to 3.92%, the contents of megastigmatrieonel 2, megastigmatrieonel 4, farnesyl acetone, dihydroactinidiolide, and geranyl acetone kept going up with increasing nicotine content. Significantly positive quadratic correlation relationship also existed between nicotine, total nitrogen and solanone, the cembratriendiol catabolite, while the solanone content was the highest at the nicotine content of 2.62% and the total nitrogen content of 2.77%, then decreased significantly. Only a very few Mallard reaction compounds had significant correlations with nicotine and total nitrogen. Aromatic amino acid catabolites, neophytadiene, and total amount of volatile aroma compounds had significant quadratic correlations with nicotine and total nitrogen contents, and at the nicotine content of 2.89% and total nitrogen content of 3.05%, the total amount of volatile aroma compounds reached maximum value.