近红外光谱法同时测定涪陵榨菜中果胶和总糖的含量

Determination of Pectin and Total Sugar in Fuling Mustard Tuber Samples by Near Infrared Spectroscopy

应用傅里叶变换近红外光谱技术,以涪陵榨菜为材料建立与其品质有关的果胶和总糖的定量分析模型。测定50份涪陵榨菜的近红外光谱数据,得到原始光谱,通过光谱预处理方法消除噪声,最后通过偏最小二乘法(PLS)建立回归模型。最终得到涪陵榨菜中果胶和总糖含量的近红外光谱分析模型,其决定系数(R2)分别为98.31、98.35,交叉验证均方差(RMSECV)分别为0.513、0.0531。用该模型对18份未知涪陵榨菜样本进行外部验证,其果胶和总糖的外部验证决定系数(R2)分别为96.69、95.63,预测集标准偏差(RMSEP)分别为0.572、0.0671。内部交叉验证和外部验证均证明,近红外定量分析有较高的准确度,能满足生产中对涪陵榨菜果胶和总糖同时测定的精度要求。

The determination of pectin and total sugar in Fuling mustard tuber samples by Fourier transform near-infrared spectroscopy（FT-NIRS） was studied.The original spectra of 50 Fuling mustard tuber samples were obtained by using FT-NIRS machine.Through math analysis,spectrum noise was decreased.Finally,the regression method was used by partial least square.Regression models between product quality and pectin or total sugar were established.The determination coefficients（R2） of the established model were 98.31 and 98.35.Its root mean square errors of cross-validation（RMSECV） were 0.513 and 0.0531,respectively.While the R2 and root mean square errors of prediction set（RMSEP） were 96.69,95.63,0.572 and 0.0671 in test set validation,respectively.Internal and external cross-validation tests exhibited that near-infrared quantitative analysis had high accuracy and could meet the requirement for predicting pectin and total sugar contents in Fuling mustard tuber products.