Effect of Ultra-High-Pressure Synergistic Different Drying Methods on Storage Quality of Cistanche deserticola.

Abstract

Post-harvest enzymatic browning in Cistanche deserticola (C. deserticola), widely used in China for food and medicine, degrades its bioactive compounds. This study evaluated the effects of ultra-high-pressure (UHP) pretreatment combined with different drying methods on phenylethanoid glycosides (PhGs) retention and assess the impact of packaging materials on storage quality and shelf life. UHP pretreatment, a non-thermal processing method, was applied before hot air drying (HA) or freeze drying (FD). Single-factor experiments and Response Surface Methodology were used for process optimization. Optimal UHP-HA conditions (296 MPa, 16 min, 81 °C) yielded a PhGs retention of 5.12 mg/g fresh weight (FW), a 1.8-fold increase compared to direct HA, while optimal UHP-FD conditions (295 MPa, 16 min, -43 °C pre-freezing) achieved a PhGs retention of 4.08 mg/g·FW, a 1.7-fold increase compared to direct FD. UHP pretreatment enhanced PhGs retention in C. deserticola by disrupting its cell walls, facilitating the release of bound compounds, and reducing enzymatic degradation during drying. In packaging, the combined use of deoxidizers and desiccants effectively maintained moisture, inhibited microbial growth, and delayed active compound degradation. Accelerated shelf-life prediction indicated that this approach could extend the shelf life of C. deserticola from 256 to 663 days. These findings offer practical strategies to enhance the quality, shelf life, and application potential of C. deserticola in functional foods and traditional medicine, with broad market potential.