Preparation and Characterization of Camellia Oil Microcapsules Using Spray Drying Coupled with Sodium Caseinate/Xanthan Gum-Stabilized Emulsion Template

To enhance the high-value utilization of camellia oil and innovation in functional foods, this study developed a stable emulsion template using xanthan gum (XG) and sodium caseinate (CAS) for the preparation of camellia oil microcapsules via spray drying. Employing scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and thermogravimetric analysis (TGA), alongside additional analytical methods, this study systematically examined the influence of drying temperature (145 °C, 165 °C, and 185 °C) and XG concentration (0.2%, 0.3%, and 0.4%) on the physicochemical properties and functional attributes of the microcapsules. Results indicated that 0.3% XG was the optimal concentration, enabling uniform emulsion droplet dispersion while balancing microcapsule bulk density and solubility, thereby optimizing processing and dissolution properties. 165 °C was identified as the optimal drying temperature, yielding the highest microcapsule yield (53.68%), moisture content (<2.84%) meeting storage standards, and optimal β-carotene encapsulation efficiency (89.6%) and DPPH radical scavenging rate (74.80 ± 0.34%). FTIR analysis confirmed successful encapsulation of camellia oil within microcapsules. TGA and in vitro digestion experiments demonstrated excellent thermal stability and digestive characteristics of the microcapsules. In summary, this study identified the most favorable preparation conditions for camellia oil microcapsules, providing theoretical support and technical reference for expanding camellia oil applications in the food industry.