Heat pump drying kinetics modeling and prediction for Lentinus edodes based on orthogonal experimental

Abstract

To accurately understand the moisture variation and drying characteristics of Lentinus edodes (L. edodes) during the drying process, the kinetics model of L. edodes with a wider application range was investigated. First, the heat pump drying kinetics model for L. edodes was fitted, verified and extended based on the orthogonal experimental data. Then, the expression of moisture ratio of L. edodes with respect to drying time, air supply temperature (AST), loading density (LD) and circulating air volume (CAV) was proposed, and interaction effects of the three key parameters on the drying time were studied based on the prediction model. The findings indicated a substantial agreement between the predicted and experimental values. The drying time could be shortened by increasing the air supply temperature and the circulating air volume or decreasing the loading density. Among these three factors, the AST had the greatest impact on drying time, followed by CAV and LD. For every 48 g/m² reduction in LD and 11.3 m³/h increase in CAV, the drying time could be reduced by 10.5–29.9 min. Similarly, increasing the AST by 1 °C and the CAV by 11.3 m³/h could decrease the drying time by 13.7–100.6 min. The research results are helpful to optimize the drying process, improve the drying efficiency, and provide guidance and references for practical production of L. edodes HPD.