高溶性虾青素在油脂体系中的氧化稳定性与降解动力学

Oxidative stability and degradation kinetics of highly soluble astaxanthin in oil systems

中文关键词:  虾青素  油脂  氧化稳定性  降解动力学  异构体

英文关键词:Astaxanthin  oil  oxidative stability  degradation kinetics  isomers

中文摘要:

      为提高虾青素在油脂体系中的溶解性与稳定性，本研究通过乙醇介质热压联合处理全反式虾青素，制备了总顺式占比为61.2%的高溶性虾青素，并系统考察其在月见草油、鱼油、芝麻油和橄榄油4种油脂基质中于?18、4、20、37 ℃条件下的氧化稳定性与降解动力学。采用HPLC分析异构体组成，结合XRD表征结晶度变化，建立一级降解动力学模型并计算活化能。结果表明，顺式异构体比例显著升高，结晶度随之降低，溶解性显著提高； 20 ℃时，总顺式占比61.2%的虾青素在4种油脂中的溶解度分别约为全反式虾青素的53、38、47和54倍；虾青素在各油脂中的降解均符合一级反应动力学，其稳定性顺序为鱼油 > 橄榄油 > 月见草油 > 芝麻油，且低温储藏显著提高其稳定性。

英文摘要:

      To improve the solubility and stability of astaxanthin in lipid systems, this study prepared highly soluble astaxanthin with a total Z-isomer proportion of 61.2% by subjecting (all-E)-astaxanthin to thermal-pressure combined treatment in an ethanol medium. The oxidative stability and degradation kinetics of the resulting product were systematically investigated in four oil matrices—evening primrose oil, fish oil, sesame oil, and olive oil—under storage temperatures of ?18, 4, 20, and 37 °C. Isomer composition was analyzed by HPLC, and crystallinity changes were characterized using XRD. A first?order degradation kinetic model was established, and activation energies were calculated. Results indicated a significant increase in the proportion of Z?isomers, leading to a corresponding decrease in crystallinity and a significant improvement in solubility. At 20?°C, the solubility of astaxanthin with 61.2% total Z-isomers in the four oils was approximately 53, 38, 47, and 54 times that of (all-E)-astaxanthin, respectively. the degradation of astaxanthin in all oils followed first?order kinetics, with stability descending in the order: fish oil > olive oil > evening primrose oil > sesame oil, low?temperature storage markedly enhanced its stability.