Experimental Evaluation of Hot Air‐Assisted Continuous Microwave Drying of Oyster Mushroom (<i>Pleurotus ostreatus</i>)

ABSTRACT This study evaluated the efficiency of hot air−assisted continuous microwave (HACM) drying for oyster mushrooms ( Pleurotus ostreatus ), focusing on drying kinetics, quality attributes, and economic feasibility. Response surface methodology was used to optimize drying parameters viz., microwave power (600–1000 W), air temperature (40°C–60°C), and airflow rate (0.5–1.5 m/s), to minimize drying time and water activity while maximizing rehydration ratio. Optimal conditions obtained were air temperature, microwave power, and air flow rate of 55.05°C, 1000 W, 0.81 m/s, respectively, with a drying time of 5 h, water activity of 0.532, and rehydration ratio of 2.49. The dried mushrooms showed 29.63% shrinkage, a total color change of 28.51, pore sizes of 2.06–15.70 µm, and a sensory acceptability score of 8.1. Proximate analysis indicated enhanced protein (33.21%) and carbohydrate (47.34%) contents. The HACM system achieved energy efficiency and specific energy consumption of 23.12% and 2.71 kWh/kg, respectively. The benefit‐cost ratio of 1.55 and a payback period of 2.56 years confirmed the economic viability of the system and its potential for scalable and high‐quality mushroom preservation.