Beyond Conventional Drying: Improving the Quality of Dried Tremella fuciformis via a Heat-Integrated Pretreatment

Hot-air drying (HAD) of Tremella fuciformis often leads to poor rehydration, yellowing, and long preparation times, lowering its industrial value. This study introduces a heat-integrated pretreatment (HIP) as a simple and viable strategy to enhance the quality of dried product. The HIP regulated water migration and preserved the polysaccharide matrix, promoting controllable conversion of bound to free water and facilitating uniform dehydration in T. fuciformis . Multi-technique analyses (Low-field nuclear magnetic resonance (LF-NMR), magnetic resonance imaging (MRI), scanning electron microscopy (SEM), rheology) confirmed that the HIP at 80°C for 5 min increased rehydration capacity by 74% over conventional methods, while maintaining structural integrity and the polysaccharide content of T. fuciformis . The suitable conditions produced bright, rehydratable, and dried T. fuciformis products with better gelation and polysaccharide retention. These results indicate the mechanism of HIP in modulating polysaccharide–water interactions and demonstrate its potential for manufacturing high-quality, quick-soak dried T. fuciformis products with enhanced functional and sensory properties.