Chemical Studies on Tobacco Smoke: IV. The Quantitative Determination of Free Nonvolatile Fatty Acids in Tobacco and Tobacco Smoke

An analytical method was developed for the determination of nonvolatile free fatty acids in tobacco and tobacco smoke. Quantitative values were secured by employing stearic acid-1-C14 as internal standard for saturated acids, and oleic acid-9,10-H3 for unsaturated acids. The method yields exact values for the six major acids within AA± 7 % and can be applied as a micro method with as little as 10 to 20 mg starting material. The major free fatty acids in tobacco were found to be in order of decreasing concentration, linolenic, palmitic, linoleic, stearic, oleic, myristic, and palmitoleic acids. Further identified were C12, C14, C15 and all saturated acids between C20 and C26. The concentrations of the acids in tobacco were found to vary between 0.6 % and 0.09 % in the six tested samples. Higher concentrations of these components were found in flue-cured and sun-cured tobaccos compared with air-cured tobacco. Coumarin was identified in the concentrated methyl esters of Turkish and bright tobaccos as well as of the blended cigarette tobacco. The analysis of cigarette smoke resulted qualitatively in a similar acid spectrum as found for tobacco. However, the concentration of the five major fatty acids was found to be at least four times higher in the particulate matter than in the original tobacco. Assuming that these fatty acids in the mainstream smoke derive from the acids originally present in tobacco, one finds a recovery rate of about 16-34 %. These findings are of interest not only to the tobacco chemist but may have even broader implications because of the possible role that nonvolatile fatty acids play in the tumour promoting activity of tobacco smoke condensate