利用VIS/NIR反射光谱快速检测柿饼加工中水分含量

Detection of Water Content During Dried Persimmon Production by Visible/near-infrared Reflectance Spectroscopy

水分是柿饼的重要组成成分,也是影响柿饼制作过程的重要因素。利用可见/近红外反射光谱对柿饼制作过程中的水分含量进行检测。首先,获取柿饼在不同加工阶段的可见/近红外反射光谱(400~1000 nm),采用烘干法测定柿饼水分含量。然后,对光谱进行Mean smoothing(MS)平滑、多元散射校正(MSC)和一阶导数(1-D)预处理。最后,对不同预处理光谱,结合样本水分含量,使用Samples set partitioning based on joint x-y distance(SPXY)方法划分校正集和验证集,基于SPA方法选择特征波长,建立多元线性回归(MLR)预测模型。结果表明,反射光谱经过MS处理后,确定的9个最优波长组合建立水分检测模型的预测结果最好:预测相关系数(Rp)为0.9690,预测标准残差(SEP)为3.4729%,可见/近红外反射光谱技术可以较好地预测柿饼制作过程中的的水分含量。研究可为柿饼加工过程中的品质快速检测提供一定的技术支撑。

Water is the component of persimmon and it is also an important factor in the process of making of dried persimmon.In this study,visible/near-infrared reflectance spectroscopy was used to detect the water content in the production of dried persimmon.Firstly,the visible/near infrared reflectance spectra(400~1000 nm)of dried persimmon at different processing stages were obtained,and the moisture content of dried persimmon was determined by drying method.After that,the reflectance spectrum were prepossessing by mean smoothing(MS),multiple scattering correction method(MSC)and the first derivative method(1-D).Finally,combined different preprocessed spectra and dried persimmon water content,the sample set partitioning based on joint x-y distances(SPXY)method was used to divided samples into calibration sets and validations sets.and then,based on the successive projections algorithm(SPA),the optimal wavelengths were selected,the multivariate linear regression(MLR)prediction models of dreid persimmon water content were established using optimal wavelength spectral signal,and the validation set samples were used to verify the prediction accuracy of the MLR model.MLR models prediction results:water content of dreid persimmon,after MS pretreatment,the MLR model established by 9 optimal wavelengths was the best,the predicted correlation coefficients(Rp)were 0.9690,and the standard error of predicted residual(SEP)were 3.4729%.The results showed that visible/near infrared reflectance spectroscopy could predict the water content in the production of persimmon better,this study provided some technical support for visible/near-infrared spectroscopy in quality detection of persimmon during process.