Kinetic characteristics and energy efficiency analysis of microwave-dried fresh ginger: Impacts of key process parameters

Microwave drying has emerged as an energy-efficient and environmentally benign alternative to conventional methods. Given the considerable nutritional and medicinal value of ginger, this study systematically investigates the effects of key parameters, such as microwave power (600–1800 W), slice thickness (1–7 mm), and loading amount (200–500 g), on drying kinetics and energy consumption of microwave-dried ginger. The mechanisms of key parameters on moisture migration and energy changes are discussed. The results reveal that the Page model best characterizes power-dependent drying, while the Midilli model better fits loading and thickness variations. Increasing microwave power considerably increases moisture diffusivity ( Deff ) and drying efficiency from 26.46% to 40.56% but reduces the specific energy consumption (Es) from 16.89 to 9.01 MJ/kg. Thickness exhibits dual effects—it improves Deff but decreases drying efficiency from 43.31% to 26.58% while increasing Es from 5.41 to 15.24 MJ/kg. Higher loading amounts improve drying efficiency from 30.05% to 42.43% and Es from 12.43 to 6.23 MJ/kg, despite slight reduction in Deff . The optimal parameters are identified as 1200–1300 W power, 350 g loading, and 2–4 mm thickness. These findings establish theoretical foundations and provide technical guidance for precision drying of high-moisture agricultural products. • Evaluated multi-parameter kinetics and energy efficiency of microwave drying. • Established quantitative models to describe the kinetic characteristics of drying. • Revealed the laws of key parameters on high efficiency-low energy consumption. • Optimal drying conditions were 1200-1300W power, 350g loading, and 2-4mm thickness. • Explored the mechanism of moisture migration and energy change for key parameters.