关键词: 载体稀释剂, 维生素E, 预混合饲料, 定量模型

Abstract: 【Objective】Vitamin E is an important feed additive, the accurate determination of its content is of great significance for the preparation of dietary. In this paper, the rapid quantitative method of vitamin E in different carrier premixed feeds was studied. The aim of this paper was to describe the applicability of near infrared spectroscopy to different carrier premixed feeds, and to establish a near-infrared rapid measuring method for vitamin content in premixed feed.【Method】Commercial vitamin E powder was collected and mixed with the silica, defatted rice bran and stone powder. The premix of vitamin E in the concentration range of 5-250 IU·g^-1was prepared by blending and collected its near-infrared spectra. This study compared the effects of different scanning times and resolution on the quality of the near infrared spectroscopy, compared the characteristic peak of vitamin E in premix of different carrier and different spectral preprocessing methods quantitative accuracy of PLS model and the difference of the model was analyzed from the point of view of VIP Score in PLS model. 【Result】 The results showed that 16 cm^-1 resolution and 32 scans were suitable for spectral acquisition. There were significant differences in NIR spectra of premix with different carriers. The vitamin E absorption peaks of silica, defatted rice bran and stone powder as the carriers of the premix were 8 700-8 200, 7 100- 7 450, 6 020-5 550, 4 440-4 200, 5 210-4 760, 8 550-8 050, 7 410, 5 950-5 200, 4 400-4 050, 4 750-4 600 cm^-1 and 8 550-8 050,   7 250, 5 950-5 200, 4 600-4 000, and 4 800-4 700 cm^-1, respectively. The optimal spectral pretreatment methods for the near-infrared quantitative models were SNV+1stDeriv（2，15）, MSC+1stDeriv（2，21）and SNV+2stDeriv（2，15）, respectively, the calibration （R_c²）were 0.988, 0.949 and 0.941, respectively, the standard error of calibration （SEP）were 8.86, 10.36 and 23.37, respectively, the validation (R_p²) are 0.989, 0.980 and 0.921 respectively, the standard error of prediction（SEP）were 8.86, 10.36 and 23.37 respectively, and ratio of performance to standard deviation（RPD）were 8.10, 6.90 and 3.07 respectively. The VIP Scores value of PLS model with three different carrier diluents were extracted, and the contribution of the VIP Score values of silica were significant and that associated with vitamin E characteristic peaks was the highest, then was the skim rice bran and followed by stone powder.【Conclusion】Near-infrared spectroscopy for the analysis of vitamin E premixed feed, with the silica and skim rice bran as the carriers of the pre-mixed feed is better, with stone powder as the carrier of premixed feed, applicability of the measuring method is poor.

Key words: carrier, vitamin E, premix feed, quantitative model