基于聚类分析法和双指标分析法的淡菜红外指纹图谱比较研究

Infrared Fingerprint Analysis of Mussel Coupled with Cluster Analysis and Sequential Analysis of Dual-indexes

目的：寻找一种快速、有效鉴别淡菜产地来源的方法。方法：利用聚类分析法和双指标分析法，对不同产地的17份淡菜样品的红外指纹图谱进行比较分析。结果：1）不同产地淡莱的红外光谱基本一致，主要显示为多糖、蛋白质和不饱和脂肪酸特征峰，但在1800—800cm。波段范围吸收峰的数目、形状和强度存在一定差异。2）应用SPSS11．5进行聚类分析。各样品红外光谱经归一化加一阶导数处理后聚类效果较为明显，但精确度相对较低；3）应用双指标序列法，共有峰率及变异峰率的计算繁琐，但可以用量化关系精确地表示各样品之间的关系。结论：本研究结果揭示红外光谱指纹图谱结合聚类分析或双指标序列法，可以快速、无损地鉴别不同产地的淡菜。为淡菜产地溯源提供1种切实可行的方法。

Objective：Developing an effective method for tracing the origin of Mussel by using infrared fingerprints. Method： The methods of cluster analysis and sequential analysis of dual-indexes were utilized to investigate the infrared fingerprints of Mussel collected from different places. Result： The Mussel from different places had the similar characteristic peaks of infrared spectra, and the IR characteristic peaks obviously appear as the main characteristic peaks with the type of protein, polysaccharide and unsaturated fatty acid bands, but there were still some differences in the number, shape and intensity of the absorption peaks in the range of fingerprint region 1 800 - 800 cm-l. Based on the infrared spectra analysis, the results indicated that the effect of cluster analysis was relatively poor and it was difficult to find out the regular sequences of 17 samples. Furthermore, the effect was improved if raw spectra were dealt with first derivative. By contrast, the 17 Mussel samples could be completely separated when the sequential analysis of dual-indexes was ap- plied, and the accurate relationship between the 17 samples could be inspected and expressed by quantitative relation- ships, but the method was more difficult than the clustering analysis if the sample size was too large, since a mass of data such as common peak ratio and variation peak ratio of the IR fingerprint spectra were processed and analyzed statistically. Conclusion： The present finding revealed that the infrared fingerprint coupled with the methods of cluster analysis and sequential analysis of dual-indexes could serve as a rapid and non-destructive analytical method for identification of Mussel from different places, and it would be a feasible way for tracing the origin of Mussel and provide a reference for geographical origin traceability of other seafood.