基于近红外光谱的普洱茶年份检测研究

Testing of pu-er tea year based on Near Infrared Spectroscopy

近红外光谱分析技术是近年发展起来的一种定性、定量分析技术,其具有快速,不破坏样品,操作简单等特点,已广泛应用于各个领域。利用近红外光谱分析技术的特点,首先对54份不同年份的普洱茶近红外光谱图吸收峰的差异进行分析,然后对普洱茶的年份进行鉴别。结果表明,随着普洱茶年份的增加,其内含主要化学成分不断减少,近红外光的吸收值也不断减少,因此波峰的尖锐程度也不断减少。随后应用聚类分析技术对不同年份的普洱茶进行定性分析,从聚类分析得到的三维立体图中可以看出,各个年份的普洱茶有比较明显的聚类现象,其中有3份茶叶样品被判断为错误,识别准确率为94.444%。

Near Infrared Spectroscopy analysis technology is a qualitative and quantitative analysis technology developed in recent years. It is fast, does not destroy the sample, runs simply, and now it has been widely used in various fields. In this paper, we use the characteristics of the Near Infrared Spectroscopy analysis technology, first analyze 54 pu- er tea＇s Near Infrared Spectrum charts of different years to identify the pu-er tea year. The research shows that increased with years of pu-er tea, the main chemical constitute reduces unceasingly, and the near-infrared light absorption value decreases, so the degree of sharp peak reduces. Then Clustering analysis technology is applied for qualitative analysis of pu-er teas of different years. From the Clustering analysis, it can be seen in the 3d stereogram that each year of pu-er tea has obvious clustering phenomena, specially, three samples of pu-er tea are judged wrong, so the recognition accuracy is 94.444%.