Abstract: Resistant starch is difficult to digest due to its physical characteristics, which can play important roles in blood glucose regulation, body weight control, cancer prevention and other physiological activities. Resistant starch has been classified into four categories depending on resistance causes. Type III resistant starch (RSIII) is a retrograded and non-granular starch that can be generated by various types of processing. In this study, the formation of RSIII in boiled rice was explored based on acid treatment and pullulanase treatment. Both treatments could increase the content of resistant starch in boiled rice. Differential scanning calorimetry analysis revealed increased initial pasting temperature, phase transition peak temperature and phase transition enthalpy of starch in boiled rice due to the increased content of resistant starch. X-ray diffraction showed that crystal structure of resistant starch in boiled rice converted into Type V from Type A . Moreover, the resistant starch achieved by these treatments revealed excellent thermal stability.

Key words: resistant starch, boiled rice, process, enzymatic reaction