Skip to main content
CORESTA Meeting, Smoke/Technology, Hamburg, 1997, ST04

Analysis of smoke fractions obtained from tobaccos extracted by supercritical carbon dioxide

ROSSI S.; BARCA L.; ALTIERI P.
A.A.M.S., Divisione Ricerche, Roma, Italy
In previous papers we described the attempt to extract some precursors of smoke from tobacco, by supercritical carbon dioxide, carrying out tests using both a bench and a pilot plant, working under the same operating conditions, with the addition in some tests of ethanol as cosolvent. The extracted fractions were analysed by capillary gas-chromatography and mass-spectrometry. The results were given in a previous paper. The crude condensates, obtained by smoking 100 plain cigarettes made with the cut tobaccos of each test and with the untreated blends, were separated by using different extracting solvents and operating at different pHs, in five fractions which where analysed by capillary gas-chromatography and mass-spectrometry. The chromatograms were shown in a previous paper. The objective of the present work is to identify as many components of the different fractions as possible. In the neutral aliphatic fraction 47 compounds were identified, mainly normal, branched and unsaturated paraffins with some low-molecular aromatic compounds as benzene-derivatives. In the neutral aromatic fraction 16 compounds were identified, such as naphtalene, indole, anthracene and some fluorene-derivatives. In the third fraction, containing the organic acids, 16 compounds were identified, mainly phenol-derivatives. In the basic fraction, besides nicotine and cotinine, 13 compounds were identified, mainly derivatives of pyridine, pyrazine, pyrazole and carbozole. In the polar neutral fraction 16 compounds were identified with alcoholic, carbonylic and amidic functions. The chromotograms of the five fractions, obtained from treated and untreated tobaccos, show that the extraction by supercritical carbon dioxide has significantly reduced: a) the normal branched and unsatured paraffins, mainly in the range C22-C31 in the aliphatic fraction; b) several compounds of aromatic fraction as naphtalene, indole, methyl-naphtalene, 3methyl-indole and others, unidentified. In the other fractions only small reductions were observed. The use of ethanol as cosolvent seems to have enhanced the extracting power of carbon dioxide only for some low-boiling compounds of aliphatic and basic fractions.