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The changes in water uptake rate, cooking property. color of rice grain, gelatinization property of milled rice during storage were studied. The water uptake rate constant of milled rice during storage at 4∼30℃ for 3 months decreased, which was more pronounced at elevated storage temperatures. The activation energy of water uptake was different below and above 25℃ of storage temperature. The activation energy after storage for 3 months below and above 25℃ was 608 and 1269 ㎈/mole, respectively. The rice grain became harder and the cooking time was prolonged by 3∼8 minutes upon storage. The cooking rate constant was linearly decreased as a function of storage time. The activation energy of cooking after 1 month of storage was 235 ㎈/mole, which was increased by 1.7 times after storage of 1.5 months and thereafter by 1.2 times with the increase of 0.5 month. There were no significant changes in color of milled rice grains during storage at 4℃, but the increase of b value was observed at higher temperatures. The initial pasting temperature of rice flour remained essentially unchanged during storage, but the peak viscosity consistently increased with the increase of storage time and temperature. The gelatinization temperature of rice flour by differential scanning calorimetry was not changed but enthalpy of gelatinization was decreased during storage.
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