Comparison of Two Methods of Estimation of the Effective Moisture Diffusivity from Drying Data

摘要

ABSTRACTThe effective moisture diffusivity (D) in starch materials was estimated by the method of slopes of the drying curve and a computer simulation technique. Drying data (moisture vs time) were obtained on slabs and spherical samples of hydrated and gelatinized starches in an air‐dryer operated at 60–100°C and air velocity 2 m/sec. The two methods gave similar results in high‐amylopectin starch gels of low porosity, where liquid diffusion might predominate during drying. Considerable differences between the two methods were found in hydrated granular starches and in porous high‐amylose gels, where vapor diffusion might be the main water transport m