Fluorescence Spectral Characteristics And Application Of Some Typical Chinese Liquors

In this thesis, fluorescence spectra of some typical liquors and major aroma components were detected, and the fluorescence spectra characteristics were analyzed and induced. By factor analysis, the thesis probed into the extent and degree of the influence exerted by aroma components upon typical liquors fluorescence. In addition, this thesis made a study of liquors discrimination based on the fluorescence characteristic parameters.The three-dimensional fluorescence spectra and three-dimensional synchronous fluorescence spectra of liquors such as Yanghe, Maotai, Wuliangye, Gujinggong and Hongxingerguotou, were obtained and the characteristics of the two kinds of fluorescence spectra were further analyzed. The results show that the outline of three-dimensional fluorescence spectra and three-dimensional synchronous fluorescence spectra differs according to the brand of the liquor. The outlines of three-dimensional fluorescence spectrum of the liquors of different varieties but the same flavor are basically the same. Moreover, the fluorescence intensity increases with the improvement of the alcohol content and quality. However, the outlines of three-dimensional synchronous fluorescence spectrum of the liquors of different varieties but the same flavor are different. The optimal excitation wavelength of three-dimensional synchronous fluorescence spectra increases with the alcohol content improved.The three-dimensional synchronous fluorescence spectra and two-dimensional synchronous fluorescence spectra ofΔλ=30nm (wavelength difference between emission and excitation) were measured and analyzed. Through the study of three-dimensional synchronous fluorescence spectra, the thesis find that the fluorescence intensity of ethyl caproate, ethyl acetate, caproic acid, lactic acid, acetal and isoamylol was greater than others. The research of two-dimensional synchronous fluorescence spectra shows that the four flavor components have different influence upon the fluorescence of two-dimensional synchronous fluorescence spectra. Acetic acid, butyric acid, and most of the alcohols and aldehydes influence the fluorescence of 260nm and 290nm upon two-dimensional synchronous fluorescence spectra of liquors. Ethyl acetate, caproic acid and lactic acid influence the fluorescence of 344nm upon two-dimensional synchronous fluorescence spectra of liquors. Ethyl caproate influence the fluorescence of 376nm upon two-dimensional synchronous fluorescence spectra of liquors.Through the factor analysis of the two-dimensional synchronous fluorescence spectra (Δλ=30nm) of liquors and aroma components, the thesis indicates that aroma components influence the fluorescence of 250-320nm and 330-400nm upon two-dimensional synchronous fluorescence spectra of liquors. Ethyl lactate, ethyl butyrate, butyric acid, acetic acid, acetal and most of the alcohols influence the fluorescence of 250-320nm upon two-dimensional synchronous fluorescence spectra of Hongxingerguotou and Gujinggong whose species were 40.6%vol, 46%vol(846) and 46%vol(946). Ethyl caproate, ethyl acetate, caproic acid, and lactic acid influence the fluorescence of 330-400nm upon two-dimensional synchronous fluorescence spectra of Wuliangye, Yanghe, Maotai and Gujinggong whose species is 45%vol-5-years.For the purpose of identifying the liquor, the thesis extracted the optimal excitation wavelength, wavelength at maximum fluorescence intensity and linewidth of maximum fluorescence emission spectra based on the three-dimensional fluorescence spectra characteristics. The twenty-eight typical liquors are divided into twenty-five categories by Fisher discriminant analysis based on the three fluorescence characteristics parameters. The results show that the three parameters could discriminate not only the brand but also the variety of the same brand.The results of the study are of great significance and importance for the further detailed research on the fluorescence spectra of liquor in the future. In addition, the thesis provide not only some help in the quality measurement and stability maintenance but also an effective way to identify the liquor.