Abstract
Properties of starch from three rice varieties in Korea, Indica types Tongil, Yusin and a Japonica type Jinheung were investigated. 1) Gelatinization temperatures of Tongil, Yushin and Jinheung rice were $72^{\circ}C,\;70^{\circ}C\;and\;68{\sim}69^{\circ}C$ respectively. Gelatinization temperature of Indica variety was higher than that of Japonica variety. 2) Blue values of Tongil, Yusin and Jinheung rice starch were 0.40, 0.39 and 0.35 respectively, in which differences among rice varieties were small. 3) Color intensity of three varieties of rice starch with iodine gave rise to absorption maxima at $610{\sim}625\;nm$. 4) Amylose contents of Tongil, Yusin and Jinheung rice starch were 23.2%, 21.3% and 20.6% respectively, which were lower than those of other cereals. Amylose content of Indica variety was higher than that of Japonica variety. 5) Alkali numbers of Tongil, Yusin and Jinheung rice starchs were 7.0, 7.0 and 6.8, respectively. The differences were negligible among rice varieties. Those values were higher than that of glutinous rice starch.
국내에서 새로이 보급된 Indica형 장려품종인 통일쌀녹말과 진흥쌀녹말의 특성을 조사한 결과는 다음과 같다. 1) 통일, 유신과 진흥쌀 호화온도는 각각 $72^{\circ}C,\;70^{\circ}C$ 및 $68{\sim}89^{\circ}C$이였다. 호화온도는 Indica 형이 Japonica형 보다 높았다. 2) 통일, 유신과 진흥쌀녹말의 blue value는 0.40, 0.39, 및 0.35이였고 품종간에 약간의 차이가 있었다. 3) 세가지 쌀품종의 녹말의 요오드정색도는 $610{\sim}625nm$에서 흡수극대를 보였다. 4) 통일, 유신과 진흥쌀녹말의 amylose 함량은 각각 23.2%, 21.3% 및 20.6%였고 이들 amylose 함량은 다른 곡물의 함량보다 낮았다. Amylose 함량은 Indica형이 Japonica형 보다 많았다. 5) 통일, 유신과 진흥쌀녹말의 alkali number는 각각 7.0 및 6.8로 품종간의 차이는 거의 없었다. 이들 값은 찹쌀녹말의 alkali number 보다 컸다.