叶黄素热稳定性及热降解动力学研究

目的考察叶黄素的热稳定性并估算其不同温度下保存时间、降解反应级数及其动力学数据。方法利用紫外分光光度法考察叶黄素含量与紫外吸收值的线性关系,并以此测定叶黄素在不同温度下热降解数据。用积分法及Arrhenius公式估算其降解反应级数和反应动力学数据以及保存时间。结果叶黄素含量与紫外吸收值呈很好的线性关系;其热降解反应为1.5级较为合适。结论其热降解反应活化能为77.16 kJ.mol-1,指前因子K0=5.66E+10h-1。在摄氏4℃下保存时间t1/2为241 d。

Thermal stability and degradation kinetics of lutein

Objective To investigate the thermal stability of lutein and to estimate the guarantee period in different temperature, degradation reaction series and the kinetics data. Methods The linear relationship were studied between the lutein content and absorption with UV spectrophotometer, and the hot degradation data of the lutein were assayed in different temperature. Estimation was made in the degradation reaction series, reaction kinetics data and guarantee period by integral method and Arrhenius formula. Results The concentration of lutein had a good linear relationship with absorbance, and the appropriate thermal degradation reaction was 1.5 order. Conclusion The values of activation energy and the preexponential factor（ K0 ） are 77.16 KJ . mol - 1 and 5.66E ＋ 10h -1 respectively. The lutein can be saved in 4°C for 241 days.