- Journal Details
- Format
- Journal
- eISSN
- 2719-9509
- First Published
- 01 Jan 1992
- Publication timeframe
- 4 times per year
- Languages
- English
Search
- Open Access
A Preliminary Study on the Fermentation Anomalies of Dark-Fired Tobacco Previously Stored in a Modified Atmosphere at High Absolute Humidity
Page range: 47 - 55
Abstract
In the course of industrial fermentation of dark-fired cigar filler leaf tobacco which was previously stored in a modified atmosphere (air and carbon dioxide), some anomalies, such as a slow temperature increase, mould development, unpleasant odours, little or no ammonia production, were observed. For the investigation of these phenomena a laboratory fermentation system was developed. This model system made it possible to change the values of the main parameters influencing the course of fermentation, to take samples for microbiological and chemical analyses, and to carry out some qualitative evaluations. Fermentations of tobacco stored in modified atmosphere and artificially inoculated with bacteria (Gen. Bacillus) were carried out.
- Open Access
Determination of Free and Bound Maleic Hydrazide Residues in Tobacco by High Performance Liquid Chromatography
Page range: 57 - 64
Abstract
A new method is described for the qualitative and quantitative determination of both free and bound maleic hydrazide residues in tobacco leaves and cigarette filler by high performance liquid chromatography. Analyses were carried out by hydrolyzing samples of ground tobacco with 4 N hydrochloric acid for 40 minutes under reflux followed by sample chromatography, running isocratic elutions with a dilute solution of phosphoric acid. The quantitative determination of maleic hydrazide was performed by light absorption at 320 nm, by the calibration curve method. Recoveries of maleic hydrazide added to tobacco samples were greater than 90 %. The detection limit of the method, determined on ground tobacco leaves, was at least 5 ppm. The results obtained by this procedure and by the ISO standard method no. 4876 are in good accordance.
- Open Access
Determination of Residues of Eight Synthetic Pyrethroids in Tobacco by Capillary Gas Chromatography
Page range: 65 - 75
Abstract
A method was developed for the simultaneous determination of the residues of the following eight synthetic pyrethroids and their isomers in tobacco: tetramethrin, permethrin, cyfluthrin, cypermethrin, alfamethrin, flucythrinate, fluvalinate and deltamethrin. The pesticides were extracted from ground tobacco by means of acetone:water 9:1 for 5 hours. The extract was diluted with water and partitioned into n-hexane. The organic phase was concentrated to about 1 ml and then purified by a Florisil-SPE column. The gas-chromatographic analyses were run with a gas-chromatograph Carlo Erba Series Mega HRGC 5300 equipped with a capillary column (stationary phase OV-1 - 0.10-0.15 µm film thickness, 25 m long) and a 63Ni electron-capture detector. Two different injection ports were used: split-splitless and cold split-splitless, working both with isothermal and programmed temperatures. Both the limit of detection and the limit of determination were estimated for each compound. Recoveries from fortified samples at level of 1 µgKg-1 are reported.
- Open Access
Determination of 25 Low Molecular Weight Carbohydrates in Tobacco by High Performance Ion Chromatography
Page range: 77 - 84
Abstract
A High Performance Ion Chromatographic method for the qualitative and quantitative determination of low molecular weight carbohydrates in tobacco leaf is described. The carbohydrates were separated by running isocratic or gradient elutions on columns packed with amino-modified polystyrene divinylbenzene phases, using 0.1 N NaOH as eluent. The compounds were detected by a Pulsed Amperometric Detector, after post-column addition of 1 N NaOH solution. Twenty-two and twenty-four carbohydrates out of twenty-five were separated by isocratic and gradient elution, respectively. Some mono and disaccharides were identified in tobacco samples by their retention times and some quantitative determinations of glucose, fructose, inositol and saccharose were carried out using different varieties of tobacco.