New approach to optimize near-infrared spectra with design of experiments and determination of milk compounds as influence factors for changing milk over time

摘要

The optimization of near-infrared spectroscopic parameters was realized via design of experiments. With this new approach objectivity can be integrated into conventional, rather subjective approaches. The investigated factors are layer thickness, number of scans and temperature during measurement. Response variables in the full factorial design consisted of absorption intensity, signal-to-noise ratio and reproducibility of the spectra. Optimized factorial combinations have been found to be 0.5 mm layer thickness, 64 scans and 25 circle C ambient temperature for liquid milk measurements.