Hot air drying characteristics of six year old cooked ginseng root at temperature ranges of 55∼75℃ under 1.8m/sec air velocity and shrinkages accompained were investigated.
Drying time to reach equilibrium moisture content of the root takes from 20 to 30 hours, depending on the subjected drying temperatures and root sizes.
Drying curve shows that it has two or three falling stages and drying constant are continuously changed. Higher drying constant was observed both at early and late stages of drying.
Shrinkage ratio of length, diameters, surface area and volume of the root were 13.0, 39.8, 47.7 and 68.5%, respectively, after 40 hours dry at 55℃. The most of shrinkage was observed at early drying stage.
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