不同发酵茶叶的红外光谱特征

Detecting Different Teas by Fourier Transform Infrared Spectroscopy

采用傅里叶变换红外光谱法,比较分析了不发酵茶、半发酵茶和全发酵茶红外特征谱的异同。结果显示,3类茶叶的红外光谱比较相似,但由于发酵程度不同,3类茶中茶多酚类物质成分的含量不同,因而具有一些各自的红外特征谱。研究表明,茶叶的不同发酵程度与茶叶的红外特征谱中的1037,1147,1324,1520和1240cm-1附近吸收峰的强度和峰形密切相关。探索了这两者之间的联系,发现根据茶叶样品的红外光谱特征峰的不同吸光度和峰形,可以区分茶叶的不同发酵程度。

Unzymic Biluochun tea,zymic Pu-er tea,and half-zymic Oolong tea,were distinguished by Fourier transform infrared spectroscopy.Although they＇re similar in infrared spectrum,the results still show differences in the characteristic peaks of infrared spectrum caused by difference between three kinds of teas of different zymic degree.The results show that zymic degrees of teas tie up with variety of absorbance band at about 1037,1147,1324,1520 and 1240 cm -1.According to the studies of the spectral peaks and absorbance rations,unzymic,half-zymic and zymic teas can be easily identified.