Changes in Sugar and Starch Contents During Storage of New Type Sweet Potato (Low β-Amylase Activity in Roots)

Development of Snack Foods Producted from Sweet Potatoes Part V

Abstract

Sugars and starch were analyzed during 6 month' storage (at 13°C) of low β-amylase activity Kyushu No. 98 sweet potato. The following results were obtained. (1) Reducing sugar content remarkably increased from 1.5% (dry basis) to 6.9% during storage of the first one month, and through the remaining storage period, showed high accumulation above 5.0%. (2) Non-reducing sugar content increased linearly from 4.4% to 14.2% during storage. (3) Starch content conversely decreased from 76.8% to 66.7%. (4) These results suggested that changes in sugar and starch content of low β-amylase activity sweet potato during storage were approximately similar to those of old type sweet potatoes. (5) The content of reducing sugar highly accumulated in roots stored for a long period didn't decreased by reconditioning under 20-30°C for 14d ays. (6) β-amylase activity in roots was invariably low during storage therefore, in this sweet potato maltose were not increased by cooking at all times.