Abstract:Aiming at the bottleneck problem of poor astaxanthin stability that restricts its application, this study aims to improve the stability of astaxanthin microcapsules by optimizing the wall material and adding antioxidants. The microcapsules encapsulated with three wall materials were prepared by spray drying method and characterized by heating, light, and storage in terms of physicochemical properties, micromorphology, differential scanning calorimetry, and infrared spectroscopy, and combined with antioxidants to improve their stability. The results showed that compared with gelatin and calcium lignosulfonate, astaxanthin encapsulated with sodium starch octenyl succinate (SSOS), maltodextrin, and sucrose as the wall material 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%, and the angle of repose was 27.25 °, and the encapsulation efficiency was 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 good encapsulation. The microcapsules showed 1.62-fold and 1.11-fold increase in retention of astaxanthin over free astaxanthin after heating and light exposure; the retention was as high as 98.45% and 97.27% when stored for 160 days at 4 ℃ and ambient temperature; and the retention was predicted to reach 2.84 years in combination with tea polyphenol palmitate (TP) and tert-butylhydroquinone (TBHQ). The results provide theoretical guidance for the application of astaxanthin microcapsules in the fields of food and aquaculture.
