실온 및 고온 저장시 쌀밥의 노화 속도

Staling Rate of Cooked Rice Stored at $21^{\circ}C$ and $72^{\circ}C$

아끼바레 및 밀양 23호 쌀을 취반한 후 실온$(21^{\circ}C)$ 및 고온 $(72^{\circ}C)$에 보관하면서, 밥알의 경도변화로부터 노화속도를 측정한 결과, 품종간의 노화속도에는 차이가 없었다. 그러나 고온 저장시가 실온 저장시보다 노화속도가 약 1.5배 늦었다.

Staling rates of cooked rice from Akibare (Japonica) and Milyang 23 (Indica) stored at $21^{\circ}C$ and $72^{\circ}C$ were analyzed using the expression ${\theta}={\exp}\;(-kt^n)$, where ${\theta}$ in the fraction of uncrystallized material remaining after time t. The values for the rate constant (k) indicated that the firming process for both rices was not dependent on the variety, but was dependent on the storage temperature. The Avrami exponent (n) was found to be unity at two temperatures, suggesting that the staling of cooked rice is characterized by instantaneous nucleation followed by rod-like growth of starch crystals.