micro PTFE10 mm × 3 mm ที่ 200 rpm The enzymatic activity was stopped after the completion of each digestion time by adding4 volumes of absolute ethanol. The glucose concentration in the supernatant was determined by using a glucose oxidase colorimetric analysis kit (TR-1511-200 Thermo Electron Noble Park, Victoria, Australia) and the factor 0.9 was used to convert anhydrous glucose released to the percentage starch hydrolysis. The residue after repeated washing (×3) was dried under vacuum at 40◦C and observed using scanning electron microscopy as described previously