Comparison of Physicochemical Properties and Stability of Astaxanthin Microcapsules Based on Wall Materials and Antioxidant Strategies

CHEN Jialing; ZHOU Lesong; WANG Haifang; XIAO Jie; ZHU Jimei; CAO Yong; LIU Xiaojuan

doi:10.13982/j.mfst.1673-9078.2026.1.1526

Abstract：The improvement in stability of astaxanthin microcapsules was assessed by optimizing wall materials and adding antioxidants to address the bottleneck of poor astaxanthin stability that limits its application.Microcapsules with three different wall materials were prepared by spray drying and characterized in terms of their physicochemical properties,micromorphology,differential scanning calorimetry,and infrared spectroscopy.Their stability was evaluated under heating,light exposure,and storage conditions,and further enhanced by the addition of antioxidants.The results showed that,compared with gelatin and calcium lignosulfonate,astaxanthin encapsulated with sodium starch octenyl succinate(SSOS),maltodextrin,and sucrose as wall materials had the smallest emulsion particle size(221.10 nm)and the highest centrifugal stability.The microcapsule particle size was 12.40 μm,with a solubility of 96.58%,an angle of repose of 27.25°,and an encapsulation efficiency as high as 92.85%.Scanning electron microscopy showed that the surface had few folds and no cracks.Differential scanning calorimetry and infrared spectroscopy analyses also showed effective encapsulation.After heating and light exposure,the retention of astaxanthin in the microcapsules increased by 1.62-fold and 1.11-fold compared with those of free astaxanthin.The retention remained as high as 98.45%and 97.27%during storage at 4℃and room temperature,respectively,for 160 days.When combined with tea polyphenol palmitate(TP)and tert-butylhydroquinone(TBHQ),the predicted shelf life of the microcapsules was extended to 2.84 years.In conclusion,SSOS,as the primary wall material,in combination with TP and TBHQ,resulted in astaxanthin microcapsules with excellent performance and high stability.The results provide theoretical guidance for the application of astaxanthin microcapsules in the fields of food and aquaculture.