近红外漫反射光谱检测梨内部指标可溶性固性物的研究

旨在建立近红外漫反射光谱与梨水果内部可溶性固形物之间的关系，以评价近红外漫反射光谱在测量梨水果内部指标可溶性固形物的应用价值。应用近红外光谱(350～1 800 nm)，采用多元线性回归(MLR)、主成分回归(PCR)和偏最小二乘法(PLS)三种不同的数学校正方法对梨水果的可溶性固形物(SSC)进行了定量分析，并且对梨水果不同位置的吸光度原始光谱，一阶微分和二阶微分三种不同预处理情况下的模型进行了最优化分析。在梨水果赤道部位预测结果较为理想，采用一阶微分预处理方法下应用PLS方法。研究结果为预测集的相关系数为0.851 7, 预测样本均方根误差为0.879 3。研究表明，近红外漫反射光谱可以作为一种准确、可靠和无损的检测方法用于评价梨水果内部指标可溶性固形物。

Research on the Soluble Solids Content of Pear Internal Quality Index by Near-Infrared Diffuse Reflectance Spectroscopy

The objectives of the present study were to establish the relationships between the near-infrared diffuse reflectance(NIR)spectra and the soluble solids content(SSC)of internal quality index of pear fruit,and to evaluate the value of NIR spectrometry in measuring the SSC of internal quality index of pear fruit.NIR spectroscopy in the 350-1 800 nm range was used to analyze the SSC of internal quality index of pear fruit with multi-linear regression(MLR),principal component regression(PCR)and partial least square(PLS)regression.Meanwhile,the best combinations of different positions at pear fruit,the logarithms of the reflectance reciprocal log(1/R),its first derivative D1log(1/R)and second derivative D2log(1/R)were investigated.The best prediction results,based on the comparative analysis,were obtained with the PLS model and D1log(1/R)at equatorial position of pear fruit.The results show that the predictions with PLS models,based on D1log(1/R)at equatorial position of pear fruit,are correlation coefficients(Rp)of 0.851 7 and root mean standard error of prediction(RMSEP)of 0.879 3 for SSC.The preliminary research on the built models indicates that NIR spectroscopy could provide an accurate,reliable and nondestructive method for assessing the SSC of internal quality index of pear fruit.