Potential estimation of major mineral contents in cow milk using mid-infrared spectrometry

Spectral variability of the 1,543 collected milk samples. The gray background represents the spectral variability of the collected samples (all spectra are plotted). The continuous black line presents the standard deviation for the 1,060 spectral data points.

Reference calcium contents measured by inductively coupled plasma atomic emission spectroscopy from the 57 samples initially selected.

Calcium contents predicted by mid-infrared spectrometry using the calibration equation of calcium developed from 57 samples.

Relation between the reference contents of calcium and phosphorus measured by inductively coupled plasma atomic emission spectroscopy and prediction of Ca and P by mid-infrared spectrometry using the second calibration equation established for Ca and P for the samples selected for the third calibration set.