Four types of sweet potato varieties namely, white skin and yellowred
flesh color (Kratai cultivar) (SP1_W_YR), purple skin and purple
flesh color (Torpuag cultivar) (SP2_P_P), purple skin and yellow
flesh color (Kaset cultivar) (SP3_P_Y) and orange- purple skin and
orange flesh color (Khai cultivar) (SP4_OP_O); and mung bean starch
produced by SitThiNan Co., Ltd. were purchased from Thailand. All
used chemicals and reagents were in analytical grade.