红外光谱结合化学计量学对朝天椒和涮涮辣的研究

Infrared Spectroscopy Combined with Chemometrics to Study Capsicum frutescens var and Shuanshuan Pepper

本文利用红外光谱结合主成分（PCA）和偏最小二乘法判别分析（PLS-DA）研究了朝天椒（簇生椒）和涮涮辣。测试了2种辣椒60个样品的红外光谱,对光谱范围1800～950cm^-1做二阶导数处理,发现在该区间存在着明显的差异,利用该区间二阶导数光谱数据进行主成分分析和偏最小二乘法,结果表明PCA和PLSDA都能很好的区别两种辣椒,其中主成分的正确率为100%,偏最小二乘法在隐含潜含变量为12个时其正确率最好,朝天椒的正确率为86.7%,涮涮辣的正确率为93.3%。结果表明小波变换结合PCA和PLS-DA用于傅里叶变换红外光谱技术中能够准确地识别朝天椒和涮涮辣,为区分不同品种的辣椒提供快速和有效的方法。

Fourier transform infrared（FTIR）spectroscopy combined with principal component analysis（PCA）and partial least squares discriminant analysis（PLS-DA）were used to study Capsicum frutescens var and shuanshuan pepper.FTIR spectra of 60 samples of 2species of Capsicum frutescens L were obtained,the results showed that the infrared spectra of Capsicum frutescens L were similar,but tiny differences in wave-numbers and absorption intensities of peaks were observed in the range of 1800～950cm^-1.PCA and PLS-DA were performed on the second derivative infrared spectra in this range.Results show that the PCA and PLS-DA can distinguish two kinds of chili peppers.PCA provides about 100% of classification accuracy,and PLS-DA yield 86.7% classification accuracy for Capsicum frutescens var and 93.3%for shuanshuan pepper.It is proved that FTIR spectroscopy combined with PCA and PLS-DA could be used to discriminate Capsicum frutescens var and shuanshuan pepper.