铁观音中茶多酚含量的近红外光谱检测模型分析

Study on Near Infrared Spectroscopic Detection Model of Tea Polyphenols in Tieguanyin

利用近红外光谱分析(NIR)技术对安徽产地铁观音名茶茶多酚含量模型进行定量分析,通过不同的光谱预处理方法比较,得出最优的光谱预处理方法,同时结合偏最小二乘法(PLS)在近红外特征吸收峰波段1872 nm与2218 nm建立茶叶的茶多酚含量模型.从建立的样本校正集模型相关系数R和均方根误差RMSEP分析发现,1872 nm处的模型R=0.9624、RMSEP=0.01648精度较好,以此模型为标准得出预测集样本茶多酚含量,并建立茶多酚化学值和预测值的相关关系图.该法可对茶叶中茶多酚含量的快速无损检测提供参考.

Near Infrared Spectroscopy(NIR)was used to quantitatively analyze the content model of tea polyphenols in Tieguanyin,the famous tea from Anhui province.By comparing different spectral pretreatment methods,the optimal spectral pretreatment method was obtained.At the same time combined with partial least squares(PLS)in the near infrared characteristic absorption peak wavelength of 1872 nm to 2218 nm tea polyphenols content model is set up.The results show that the accuracy of the model R=0.9624 and RMSEP=0.01648 at 1872 nm is better from the perspective of the parameters of the established sample correction set model R(correlation coefficient)and RMSEP(root mean square error).The model is used as the standard to obtain the content of tea polyphenols in the predicted set,and the correlation diagram between the chemical value of tea polyphenols and the predicted value is established.It can provide reference for rapid nondestructive testing of tea polyphenols in tea.