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Gelatinization and retrogradatien properties of modified starches which were prepared by steeping sweet potato at 40℃ for 2, 4, 7 and 10 days were investigated. The peak temperature of gelatinization and enthalpy of untreated starch ty DSC were 53.9℃ and 1.32 cal/g, respectively, but those of modified starch were increased by steepirg. In gelatinization by alkali, starches with 2, 4 and 7 day steeping showed higher viscosities than ur treated starch, whereas the viscosities of starches with 10 day steeping decreased. The clarities in pa:,te decreased during storage in all starches and decreased in starches with steeping. The degrees of retrogradation by α-amylase-iodine method were higher in starches with steeping than untreated starch. The enthalpy of retrograded starches by DSC increased by steeping except 4 day steeping s:arch. The sweet potato extract containing sugar inhibited the retrogradation of starch paste and the degree were higher in residual starches than in untreated starch.
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