Rodriguez-Otero J L, Hermida M, Cepeda A
Universeidade de Santiago de Compostela, Departamento de Química Analítica, Nutrición y Bromatología, Facultad de Veterinaria, Lugo, Spain.
J AOAC Int. 1995 May-Jun;78(3):802-6.
Near-infrared reflectance (NIR) spectroscopy was used to analyze fat, protein, and total solids in cheese without any sample treatment. A set of 92 samples of cow's milk cheese was used for instrument calibration by principal components analysis and modified partial least-square regression. The following statistical values were obtained: standard error of calibration (SEC) = 0.388 and squared correlation coefficient (R2) = 0.99 for fat, SEC = 0.397 and R2 = 0.98 for protein, and SEC = 0.412 and R2 = 0.99 for total solids. To validate the calibration, an independent set of 25 cheese samples of the same type was used. Standard errors of validation were 0.47, 0.50, and 0.61 for fat, protein, and total solids, respectively, and R2 for the regression of measurements by reference methods versus measurements by NIR spectroscopy was 0.98 for the 3 components.
采用近红外反射（NIR）光谱法在不对样品进行任何处理的情况下分析奶酪中的脂肪、蛋白质和总固形物。使用一组92个牛奶干酪样品，通过主成分分析和改进的偏最小二乘回归进行仪器校准。得到以下统计值：脂肪的校准标准误差（SEC）=0.388，平方相关系数（R2）=0.99；蛋白质的SEC=0.397，R2=0.98；总固形物的SEC=0.412，R2=0.99。为验证校准，使用了一组独立的25个相同类型的干酪样品。脂肪、蛋白质和总固形物的验证标准误差分别为0.47、0.50和0.61，参考方法测量值与近红外光谱法测量值的回归R2对于这三种成分均为0.98。
