Advantages of Multiphase Microwave Drying (MMD) Technology in Shiitake Mushroom Processing: Dual Optimization of Efficiency and Quality

Multi-phase microwave drying (MMD) uses microwaves as a heat source while adjusting chamber pressure to dry materials, enabling solid-liquid-gas phase transitions of water. This method significantly shortens drying time and reduces energy consumption. This study explores MMD’s feasibility as an efficient and high-quality drying technique for shiitake mushrooms, comparing it with hot air drying (HAD), heat pump drying (HPD), freeze drying (FD), and microwave vacuum drying (MVD). The results show MMD dries mushrooms in 105 minutes, achieving speeds 5, 7, and 13 times faster than HAD, HPD, and FD, respectively. MMD also significantly reduces shrinkage (14.0%) and improves rehydration (519.4%), surpassing HAD, HPD, and MVD by 66.79%, 60.99%, and 269.53%. Additionally, MMD better preserves volatile compounds and the mushrooms’ original flavor, reducing losses due to overheating. Nutritionally, MMD retains higher levels of amino acids (34.92 mg/g) and nucleotides (160.31 mg/100 g), boosting umami flavor (786.96 g MSG/100 g). This method combines microwave drying’s efficiency with freeze drying’s quality benefits.