The Pattern Recognition Research On The Fingerprint Of Base Luzhou-flavor Liquor

The grade of luzhou-flavor liquor has been assessed using the traditional sensory evaluation. This way is practically necessary but lack of a certain scientific nature due to the impact of human factor. In order to make the identification and evaluation of base luzhou-flavor liquor more objective and figurative, the fingerprints of trace flavor ingredients were detected by gas chromatography, and the pattern recognition methods including similarity analysis, hierachical clustering analysis and principal component analysis(PCA) were used to identify and distinguish different grades of base luzhou-flavor liquor. Also the quality evaluation model of base luzhou-flavor liquor was established by analyzing the relationship between the sensory scores and the statistical datas obtained by PCA. The conclusions are as follows:1. The fingerprints of three different grades of base luzhou-flavor liquor stored half a year were established by gas chromatography. Standard fingerprints of base luzhou-flavor liquor were established by median value. Similarity of the fingerprints was calculated by the comparing on their GC profiles using two methods, namely correlation coefficient and angle cosine, respectively. The results showed that the similarity of different grades of base luzhou-flavor liquor was obviously different. Therefore, the method can be used to discriminate different grades of base luzhou-flavor liquor. In addition, the similarity was detected to discriminate different techniques of base luzhou-flavor liquor.2. The main components of the20common peaks which choosed from the fingerprints of three different grades of base luzhou-flavor liquor stored half a year using principal component analysis (PCA) were analyzed, in which the former two main components were employed to plot a two-dimensional scatter map. The map showed that the liquor samples could be distinguished obviously from different grades.3. The fingerprints of three different grades of base luzhou-flavor liquor stored half a year were established by the20representative fingerprint peaks selected from GC profiles by PCA. Discrimination of the fingerprints was performed by hierarchical cluster analysis.The results showed that the discrimination of different sensory levels of base luzhou-flavor liquor was generally the same with the actual sensory evaluation. The consistent rate was up to96.7%.4.The quality evaluation model of base luzhou-flavor liquor stored half a year U=0.00005g3-0.0091g2+0.7061g+77.022was established by analyzing the relationship between the synthesis index of the former four main components(G) and the sensory scores(U). The effective percentage of the quality evaluation model is up to93.3by verifying the data in luzhou-flavor quality database, which indicates the evaluation model can be used in the quality control of the three different grades of base luzhou-flavor liquor stored half a year.