| The flavor compound of cigarette smoke was studied in this thesis, and the study was focus on the taste compound of cigarette smoke, which was definitely put forward for the first time. As sweet is the most accessible taste of five basic tastes, monosaccharides, the main compounds of sweet taste, were studied. Chromatographic methods for determination of monosaccharides in total particulate matter of cigarette mainstream smoke and in tobacco were established at first. Then the transfer rates of the monosaccharides from cigarette to mainstream smoke were calculated via the monosaccharides content results of cigarette and mainstream smoke. And factors influencing on the transfer rates were analyzed preliminary. The detailed results were as follows:(1) The method using high performance liquid chromatography for determination of mannose and glucose in mainstream cigarette smoke was studied. Mainstream smoke particulate was collected on Cambridge filter pad. The particulate was then extracted in a ultrasonic bath and purified by solid phase extraction cartridge. The extract was derivatized with 1-phenyl-3-methyl-5-pyrazolone and detected with ultraviolet detector at wavelength of 245nm. Monosaccharide derivatives are successfully detected on HP Hypersil ODS(125×4mm i.d., 5μm) column using equivalent elution with the mobile phase of 0.05 mol/L phosphate buffer (pH 6.8)-acetonitrile (85∶15, v/v) at flow rate of 1.0 mL/min, column temperature of 25℃with injection volume of 20μL. The results indicate that there were at least glucose and mannose which was not reported in cigarette smoke before. The content of two monosaccharides were different in mainstream smoke of different brands of cigarette. The rang of two monosaccharides were 1.87μg/cig.～9.42μg/cig. for mannose and 8.36μg/cig.～94.50μg/cig. for glucose, and there was remarkable positive correlation between mannose and glucose. The content of two monosaccharides of foreign brands and mixed type of homemade brands were low comparatively.(2) The high performance anion exchange chromatographic (HPAEC) method for determination of monosaccharides in cigarette smoke was studied. Total particulate matter was extracted in a ultrasonic bath, and detected by HPAEC with online ultrafiltration. Monosaccharides were separated on METROSEP Carb1 250 (4.6×250mm,5μm)column and RP guard, by 2.0mmol/L NaOH and 0.5mmol/L NaAc solution as mobile phase at flow rate of 1.00mL/min and 0.1mol/L NaOH as after-column derivatization at flow rate of 0.4 mL/min with injection volume of 20μL. It was validated that there were arabinose, glucose, xylose, fructose and mannose in cigarette smoke. Moreover, there was also galactose in cigarette smoke which was not reported before. The method can be used to determine the content of fructose and xylose. The results of analysis of cigarette smoke sample indicated that the order of the content of monosaccharides was fructose>glucose>arabinose>mannose>galactose>xylose. The concentration of total monosaccharides could reach the threshold of sweet taste. There were obvious inner relationships between five main monosaccharides: fructose and galactose, glucose and mannose have positive correlation, and arabinose correlates with other four monosaccharides negatively.(3) The results of quantitative analysis of mannose and glucose of cigarette tobacco showed that the content of two monosaccharides were 5.08%～10.11% for glucose and 0.201%～0.324% for mannose in cigarette tobacco. There was not statistical correlation between mannose and glucose in cigarette tobacco. Glucose of cigarette smoke and tobacco had remarkable positive correlation, and mannose of smoke wasn't correlative with that in tobacco statistically.(4) The hypothesis that the monosaccharides of cigarette smoke were transferred into the smoke simply was brought forward in this thesis. The definition of transfer rate was obtained. The transfer rates of three monosaccharides were calculated using the content of monosaccharides of cigarette smoke and tobacco. The transfer rate of glucose was 0.125%～0.176% with little fluctuation, and the transfer rate of fructose was close to glucose's. But the transfer rate of mannose was 0.325%～0.746% with a obvious change.From the results above, it was concluded as follows. The monosaccharides content in tested cigarette smoke has reached the threshold of sweet taste completely. The special correlations of main kinds of monosaccharides in cigarette smoke probably are related to harmonious taste which depends on cigarette formula. The transfer rates of glucose and fructose were lower, because they mainly existed inside tobacco. While the transfer rate of mannose is significantly higher since most mannose was added on the surface of cigarette tobacco during the manufacturing process. So it was considered that the burning characteristic of cigarette had remarkable influence on transfer rate of mannose. As the flavor of cigarette became thinner and thinner on the background of tar reduction recently, it is hoped that the conclusions obtained in this thesis are helpful to improvement of cigarette taste theoretically.
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