Effects of Low-Temperature Storage of Brown Rice on Rice and Cooked Rice Quality

This study was carried out to investigate the changes of brown rice, and cooking properties after milling of brown rice according to storage temperature and varieties. Brown rices were stored at $15^{\circ}C$ and $35^{\circ}C$ for 10 weeks. Tz values of brown rice stored at $35^{\circ}C$ were higher in Hwaseongbyeo, Koshihikari, Hitomebore, than the other varieties. The increasing rate of hardness of cooked rice in Odaebyeo, Junghwabyeo, Sangmibyeo stored at $35^{\circ}C$ were lower than those of other varieties. In stored brown rice at $15^{\circ}C$ and $35^{\circ}C$, correlations between pH of brown rice and fat acidity, hardness, b value of cooked milled rice and head rice rate of milled rice were significant $0.743^{**}$, $0.539^*$, $-0.693^{**}$, 0.250, respectively. At $15^{\circ}C$ and $35^{\circ}C$, correlations between L value and b value of cooked milled rice, head rice rate of milled rice were significant $-0.772^{**}$, $0.638^*$, and those between fat acidity of brown rice and consistency of milled rice were $0.604^*$. In brown rice stored at $15^{\circ}C$, It was higher quality of milled rice and cooked rice than those at $35^{\circ}C$ that increased head rice rates of milled rice and glossy value of cooked milled rice but lower color b value and hardness of cooked rice.

현미 저온저장이 쌀과 밥의 품질에 미치는 영향

현미저장 중 저장온도에 따른 쌀과 밥의 품질변화를 구명하고자 추청벼 등 14품종의 현미를 $15^{\circ}C$와 $35^{\circ}C$에 10주간 저장 후 현미 및 백미, 밥의 품질관련 특성을 조사하였다. 1. $15^{\circ}C$저장이 $35^{\circ}C$에 비하여 현미의 Tz값이 높아 배아 활성 정도가 높았으며 도정 후 백미 완전미율이 높아 $15^{\circ}C$ 저장 쌀의 품질이 양호하였다. 2. $35^{\circ}C$에 비하여 $15^{\circ}C$에 저장한 현미에서 쌀밥의 윤기치는 높았으나, 밥 색도 b 값, 밥 경도, 호화점도(최종점도, 강하점도)가 낮아 밥의 품질이 우수하였다. 3. 밥 색도 b값은 조생종이 중.만생종에 비하여 높았고, 밥 경도는 조생종이 낮았으며, 저장 현미의 도정 후 백미 완전미율은 $15^{\circ}C$에서 78%, $35^{\circ}C$에서 70%이었으며 $35^{\circ}C$에서 화성벼, 추청벼, 남평벼는 82%이상을 나타냈다. 4. $15^{\circ}C$ 저장에서 밥 색도 b값은 pH와 $-0.693^{**}$, 윤기치와 $-0.823^{**}$, L값과 $-0.772^{**}$, 지방산도와 $-0.548^*$, 백미 완전미율과 $-0.576*$, L값과 $-0.772^{**}$, a값과 $0.557*$ 의 유의성을 나타냈으며, 백미 완전미율은 밥색도 L값과 $0.638*$, 밥색도 b값과 $-0.576*$의 유의성을 나타냈다.