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Starch samples of rice and glutinous rice starches were adjusted to 27 % of moisture and heated at 100℃ for 16 hours, respectively. After the treatment, their physicochemical properties were investigated. The granule shapes of all the starches were polygonal and they became slightly bigger in their sizes after the treatment. All their X-ray diffraction patterns were A types. The specific gravity of the starches decreased to 1.03-1.09 by the treatment. The water binding capacity of rice starches increased, while that of glutinous counterparts slightly decreased. Almost no change in the amount of amylose included was found. Swelling power and solubility were increased with the increase of temperature. At a certain temperature, however, the solubility of the treated starches increased when the swelling power decreased. The initial gelatinization temperatures of Akkibare, Yongmun, and Taebaek starches were 60∼65℃ but those of glutinous rice starch and U.S.A. rice starch were 55∼60℃ and 70∼75℃, respectively, as measured by transmittance. The gelatinization temperature of the treated starches was higher than that of the untreated starches.
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