婴儿配方乳粉中蛋白质的光学快速检测方法对比研究

Comparative Research on Optical Rapid Detection Methods for Proteins in Infant Formula Milk Powder

目的:研究近红外光谱法(Near Infrared Spectroscopy,NIR)和中红外光谱法(Mid Infrared Spectroscopy,MIR)的蛋白质快速检测建模方法,为婴儿配方乳粉中蛋白质含量的快速测定提供参考。方法:确定乳粉样品的光谱扫描条件,选择建模算法,研究基线校正、标准正态变换、多元散射校正和一阶导数等预处理方法,利用交互验证和外部检验对模型的可靠性进行评价。结果:近红外模型经过标准正态变换预处理后模型的相关系数r为0.906,交互验证标准误差为0.11,用此模型对测试集的15个样品进行验证,样品预测值和化学测定值之间的相关系数为0.947;中红外模型的相关系数r和交互验证标准误差分别为0.633和0.15,对测试集15个样品进行验证,样品预测值和化学测定值之间的相关系数为0.685。结论:近红外光谱建模方法准确、快速、简便,可用于婴儿配方乳粉中蛋白质含量的快速测定。中红外光谱建模方法不适用于婴儿配方乳粉中蛋白质含量的快速测定。

Objective:To study the modeling methods of near infrared spectroscopy(NIR)and mid infrared spectroscopy(MIR)for the rapid detection of protein in infant formula milk powder.Method:The spectral scanning conditions of the milk powder samples were determined,and modeling algorithms were selected.Pre processing methods such as baseline correction,standard normal variate transform,multivariate scattering correction,and first derivative were studied.The reliability of the model was evaluated using interactive validation and external validation.Result:The correlation coefficient(r)of the near-infrared model after standard normal variate transform preprocessing was 0.906,and standard error of cross validation(SECV)was 0.11.This model was used to validate 15 samples in the test set,and the correlation coefficient between the measured and predicted values of the samples was 0.947;the correlation coefficient(r)and SECV of the mid infrared model were 0.633 and 0.15.The correlation coefficient between the measured and predicted values of 15 samples in the test set was 0.685.Conclusion:The near infrared spectroscopy modeling method is accurate,fast,and simple,and can be used for rapid determination of protein content in infant formula milk powder.The mid infrared spectroscopy modeling method is not suitable for rapid determination of protein content in infant formula milk powder.