Application of near-infrared spectroscopy in the detection of fat-soluble vitamins in premix feed

Vitamin is the organic compound and necessary for animal physiological maintenance. The rapid determination of the content of different vitamins in premix feed can help to achieve accurate diets and efficient feeding. Compared with high-performance liquid chromatography and other wet chemical methods, near-infrared spectroscopy is a fast, non-destructive, non-polluting method. 168 samples of premix feed were collected and the contents of vitamin A, vitamin E and vitamin D₃ were detected by the standard method. The near-infrared spectra of samples ranging from 10 000 to 4 000 cm^-1 were obtained. Partial least squares regression (PLSR) and support vector machine regression (SVMR) were used to construct the quantitative model. The results showed that the RMSEP of PLSR model of vitamin A, vitamin E and vitamin D₃ were 0.43×10⁷ IU/kg, 0.09×10⁵ IU/kg and 0.17×10⁷ IU/kg, respectively. The RMSEP of SVMR model was 0.45×10⁷ IU/kg, 0.11×10⁵ IU/kg and 0.18×10⁷ IU/kg. Compared with nonlinear regression method (SVMR), linear regression method (PLSR) is more suitable for the quantitative analysis of vitamins in premix feed.