Effect of Cold Treatment after Harvest on Sugar Contents and Storability in Sweet Potato (Ipomoea batatas L.)

Abstract

The effect of cold treatment on sugar concentration, sweetness and decay in Ipomoea roots was studied. Storage temperature were 3, 5, 10 and 13°C. Sugar concentrations, with the exception of maltose, varied significantly with changes in storage temperatures from 3 to 13°C. The sucrose concentrations in roots stored at 3 to 5°C increased more rapidly than that at 10 to 13°C. In contrast to the change in sucrose concentration, glucose and fructose concentrations increased slightly during storage at 3 to 5°C, whereas these concentrations increased significantly during storage at 10 to 13°C. Consequently, the sweetness calculated from these sugar concentrations was higher at 5 or 10°C storage than at other temperatures. However, roots stored at 5°C exhibited decay as a result of chilling injury. These observations suggest that storage at 10°C is more effective for increasing sweetness in Ipomoea roots.