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Detalles de la revista
Formato
Revista
eISSN
2719-9509
Publicado por primera vez
01 Jan 1992
Periodo de publicación
4 veces al año
Idiomas
Inglés

Buscar

Volumen 12 (1983): Edición 1 (February 1983)

Detalles de la revista
Formato
Revista
eISSN
2719-9509
Publicado por primera vez
01 Jan 1992
Periodo de publicación
4 veces al año
Idiomas
Inglés

Buscar

6 Artículos
Acceso abierto

Migration and Delivery of Filter Flavours

Publicado en línea: 14 Aug 2014
Páginas: 1 - 8

Resumen

Abstract

The migration and delivery of filter flavour agents were studied by dissolving 10 model flavour compounds in triacetin at 10 mg/ml each and fabricating cigarettes with flavoured filter tips. The concentrations of these compounds in filters, tobacco, and smoke particulates collected on Cambridge filters were determined by capillary column gas chromatography initially and after 1, 2, 4, 6, and 8 weeks. Flavour migration was found to obey first-order kinetics, with the rate constant being determined by the volatility of the flavour compound dissolved in the plasticized filter. Delivery of flavour compounds decreased with time at a greater rate than could be explained by flavour migration. A high correlation between the solubility characteristics of the flavour and its rate of delivery efficiency loss lead to the proposed explanation that flavour compounds diffuse into the cellulose acetate fibers with time and become less accessible for elution into the smoke aerosol. Model compounds with poor solubilities in plasticized cellulose acetate remain near the surface of the fibers where they are readily eluted into the mainstream smoke and, consequently, exhibit smaller delivery efficiency losses with time. Ventilation was observed to initially increase the ratio of flavour to TPM delivery, but this advantage was lost as the cigarette aged.

Acceso abierto

Investigation of an Odour Problem on Cigarette Packets

Publicado en línea: 14 Aug 2014
Páginas: 9 - 13

Resumen

Abstract

The cause of an odour in certain packets of a batch of cigarettes has been investigated. Two compounds identified as being responsible for the odour were 1,4-dioxaspiro(4,5)decane and 2-methyl-1,4-dioxaspiro(4,5)decane which were formed from the reaction of cyclohexanone, a component of the tearstrip solvent, with ethane-1,2-diol and propane-1,2-diol. These diols had been found as plasticizers in the film used for some packet overwraps but no odour was produced when diethylene glycol, the usual plasticizer, was used in the film.

Acceso abierto

Surfactant Residues in Maryland Tobacco Treated with a Fatty-Alcohol-Type Sucker-Control Formulation

Publicado en línea: 14 Aug 2014
Páginas: 15 - 19

Resumen

Abstract

Surfactant residues (Tween 80 Esters and Tween 80 free Polyols) were determined in Maryland tobacco treated with a fatty-alcohol-type sucker-control formulation. The levels of residues in leaves decreased throughout the growing and air-curing periods, but decreased the most during the first 24 hours after treatment. Factors affecting Tween 80 residue levels included dosage and location of leaves on the plant.

Acceso abierto

Selective Adsorption of Nitrate and Nitrite from Tobacco Leaf Homogenates

Publicado en línea: 14 Aug 2014
Páginas: 21 - 27

Resumen

Abstract

A procedure has been developed for the reduction of nitrate / nitrite in tobacco during the homogenized leaf curing process. This procedure involves the precipitation of these anions with a polymer composed of the nitron 1,4-diphenyl-3,5-endoanilino-4,5-dihydro-1,2,4-triazole linked to poly(vinylbenzyl chloride). This poly(vinylbenzyl-nitron chloride) complex was coated onto several inert supporting materials and tested for anion binding capacity using nitrate/nitrite standards and tobacco leaf extracts. When coated onto the surface of acid-washed sand, the nitron polymer was capable of repeated regeneration with no detectable loss of nitrate / nitrite binding capacity. The nitron polymer had a slightly greater affinity for nitrite than for nitrate; however, due to the high ratio of nitrate to nitrite in tobacco leaf tissues, nitrate was the principle anion adsorbed from leaf homogenates. Large scale application of this selective nitrate adsorbing polymer during homogenized leaf curing of tobacco could significantly reduce these potentially harmful components in smoking products.

Acceso abierto

Chlorophyllase Activity and Chlorophyll Degradation in Tobacco Chlorophyll Genotypes

Publicado en línea: 14 Aug 2014
Páginas: 29 - 33

Resumen

Abstract

Dark (Ky171) and Burley (Ky14) tobaccos, which differ in chlorophyll genotype at Yb1 and Yb2 loci, showed no difference in chlorophyllase activity in leaves of the same stalk position. Within a plant, the activity was comparable among three stalk positions in Ky14, whereas the top leaves had higher activity than bottom leaves in Ky171. Since these chlorophyll genes do not modify chlorophyllase activity, these results suggest their mode of action on chlorophyll accumulation is through biosynthesis rather than degradation. In contrast, chlorophyll-deficiency genes Py and yg showed higher chlorophyllase activity than dark and Burley genotypes. This was further substantiated by the loss of 14C-chlorophyll specific activity in a pulse-labelling experiment using 14C-d-aminolevulinic acid as chlorophyll precursor. The mode of action for Py and yg genes on chlorophyll degradation is in concert with polyphenol accumulation in tobacco leaf. A metabolic scheme showing the inter-relationship between chlorophyll biosynthesis and polyphenol accumulation is presented.

Acceso abierto

Biomass and Chemical Composition of Tobacco Plants Under High Density Growth

Publicado en línea: 14 Aug 2014
Páginas: 35 - 42

Resumen

Abstract

Ten tobacco cultivars representing various tobacco types were directly seeded in the field at 70 to 80 plants per square meter and were harvested when 50 to 60 cm high. Biomass yield ranged from 44 to 70 metric tons per hectare, with Ky16 Mammoth having the highest yield. The Mammoth variety, however, had the lowest leaf/stalk ratio (1.77), whereas Coker 139 bad the highest (4.04). One metric ton of wet biomass produced about 6 to 8 kg of soluble protein, which is independent of the leaf/stalk ratio. Analyses of the deproteinized fibrous residues revealed that the levels of neutral detergent fiber, acid detergent fiber, cellulose, and apparent hemicellulose were comparable among the ten cultivars. A large variation of lignin content was observed among the dark green tobaccos. Burley, in general, had lower concentrations of starch and protein in the fibrous residue than the dark green tobacco. When compared with the deproteinized alfalfa fibrous residue, the low concentrations of lipids, lignin, and cellulose and a greater amount of apparent hemicellulose in the tobacco residue show its suitability as animal feed. The present results also indicate that the selection of tobacco genotypes is of importance for high density cultivation in the production of soluble protein and fibrous residue.

6 Artículos
Acceso abierto

Migration and Delivery of Filter Flavours

Publicado en línea: 14 Aug 2014
Páginas: 1 - 8

Resumen

Abstract

The migration and delivery of filter flavour agents were studied by dissolving 10 model flavour compounds in triacetin at 10 mg/ml each and fabricating cigarettes with flavoured filter tips. The concentrations of these compounds in filters, tobacco, and smoke particulates collected on Cambridge filters were determined by capillary column gas chromatography initially and after 1, 2, 4, 6, and 8 weeks. Flavour migration was found to obey first-order kinetics, with the rate constant being determined by the volatility of the flavour compound dissolved in the plasticized filter. Delivery of flavour compounds decreased with time at a greater rate than could be explained by flavour migration. A high correlation between the solubility characteristics of the flavour and its rate of delivery efficiency loss lead to the proposed explanation that flavour compounds diffuse into the cellulose acetate fibers with time and become less accessible for elution into the smoke aerosol. Model compounds with poor solubilities in plasticized cellulose acetate remain near the surface of the fibers where they are readily eluted into the mainstream smoke and, consequently, exhibit smaller delivery efficiency losses with time. Ventilation was observed to initially increase the ratio of flavour to TPM delivery, but this advantage was lost as the cigarette aged.

Acceso abierto

Investigation of an Odour Problem on Cigarette Packets

Publicado en línea: 14 Aug 2014
Páginas: 9 - 13

Resumen

Abstract

The cause of an odour in certain packets of a batch of cigarettes has been investigated. Two compounds identified as being responsible for the odour were 1,4-dioxaspiro(4,5)decane and 2-methyl-1,4-dioxaspiro(4,5)decane which were formed from the reaction of cyclohexanone, a component of the tearstrip solvent, with ethane-1,2-diol and propane-1,2-diol. These diols had been found as plasticizers in the film used for some packet overwraps but no odour was produced when diethylene glycol, the usual plasticizer, was used in the film.

Acceso abierto

Surfactant Residues in Maryland Tobacco Treated with a Fatty-Alcohol-Type Sucker-Control Formulation

Publicado en línea: 14 Aug 2014
Páginas: 15 - 19

Resumen

Abstract

Surfactant residues (Tween 80 Esters and Tween 80 free Polyols) were determined in Maryland tobacco treated with a fatty-alcohol-type sucker-control formulation. The levels of residues in leaves decreased throughout the growing and air-curing periods, but decreased the most during the first 24 hours after treatment. Factors affecting Tween 80 residue levels included dosage and location of leaves on the plant.

Acceso abierto

Selective Adsorption of Nitrate and Nitrite from Tobacco Leaf Homogenates

Publicado en línea: 14 Aug 2014
Páginas: 21 - 27

Resumen

Abstract

A procedure has been developed for the reduction of nitrate / nitrite in tobacco during the homogenized leaf curing process. This procedure involves the precipitation of these anions with a polymer composed of the nitron 1,4-diphenyl-3,5-endoanilino-4,5-dihydro-1,2,4-triazole linked to poly(vinylbenzyl chloride). This poly(vinylbenzyl-nitron chloride) complex was coated onto several inert supporting materials and tested for anion binding capacity using nitrate/nitrite standards and tobacco leaf extracts. When coated onto the surface of acid-washed sand, the nitron polymer was capable of repeated regeneration with no detectable loss of nitrate / nitrite binding capacity. The nitron polymer had a slightly greater affinity for nitrite than for nitrate; however, due to the high ratio of nitrate to nitrite in tobacco leaf tissues, nitrate was the principle anion adsorbed from leaf homogenates. Large scale application of this selective nitrate adsorbing polymer during homogenized leaf curing of tobacco could significantly reduce these potentially harmful components in smoking products.

Acceso abierto

Chlorophyllase Activity and Chlorophyll Degradation in Tobacco Chlorophyll Genotypes

Publicado en línea: 14 Aug 2014
Páginas: 29 - 33

Resumen

Abstract

Dark (Ky171) and Burley (Ky14) tobaccos, which differ in chlorophyll genotype at Yb1 and Yb2 loci, showed no difference in chlorophyllase activity in leaves of the same stalk position. Within a plant, the activity was comparable among three stalk positions in Ky14, whereas the top leaves had higher activity than bottom leaves in Ky171. Since these chlorophyll genes do not modify chlorophyllase activity, these results suggest their mode of action on chlorophyll accumulation is through biosynthesis rather than degradation. In contrast, chlorophyll-deficiency genes Py and yg showed higher chlorophyllase activity than dark and Burley genotypes. This was further substantiated by the loss of 14C-chlorophyll specific activity in a pulse-labelling experiment using 14C-d-aminolevulinic acid as chlorophyll precursor. The mode of action for Py and yg genes on chlorophyll degradation is in concert with polyphenol accumulation in tobacco leaf. A metabolic scheme showing the inter-relationship between chlorophyll biosynthesis and polyphenol accumulation is presented.

Acceso abierto

Biomass and Chemical Composition of Tobacco Plants Under High Density Growth

Publicado en línea: 14 Aug 2014
Páginas: 35 - 42

Resumen

Abstract

Ten tobacco cultivars representing various tobacco types were directly seeded in the field at 70 to 80 plants per square meter and were harvested when 50 to 60 cm high. Biomass yield ranged from 44 to 70 metric tons per hectare, with Ky16 Mammoth having the highest yield. The Mammoth variety, however, had the lowest leaf/stalk ratio (1.77), whereas Coker 139 bad the highest (4.04). One metric ton of wet biomass produced about 6 to 8 kg of soluble protein, which is independent of the leaf/stalk ratio. Analyses of the deproteinized fibrous residues revealed that the levels of neutral detergent fiber, acid detergent fiber, cellulose, and apparent hemicellulose were comparable among the ten cultivars. A large variation of lignin content was observed among the dark green tobaccos. Burley, in general, had lower concentrations of starch and protein in the fibrous residue than the dark green tobacco. When compared with the deproteinized alfalfa fibrous residue, the low concentrations of lipids, lignin, and cellulose and a greater amount of apparent hemicellulose in the tobacco residue show its suitability as animal feed. The present results also indicate that the selection of tobacco genotypes is of importance for high density cultivation in the production of soluble protein and fibrous residue.

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