명반이 멥쌀과 찹쌀전분의 이화학적 성질에 미치는 영향을 조사하였다. 멥쌀 및 찹쌀전분의 팽윤력은 두 전분 모두 대조구보다 명반 $0.05{sim}1.0%(w/w)$ 첨가구에서 증가하였으며, 이 농도 이상에서는 완만하게 감소하는 경향을 나타내었다. 용해도는 멥쌀전분의 경우 명반 $0.05{sim}1.0%(w/w)$ 첨가구에서는 온도증가에 따라 점차 증가한 반면, 찹쌀전분의 경우는 온도에 관계없이 감소하였으며, 이농도 이상에서는 두 전분 모두 거의 변화를 보이지 않았다. Blue value값은 명반농도가 증가할수록 멥쌀전분의 경우는 증가한 반면, 찹쌀전분에서는 감소하였다. Amylography에 의한 호화양상에 있어서는 명반 1.0%(w/w) 첨가가 멥쌀 및 찹쌀전분의 호화개시 온도와 breakdown값을 증가시켰고 setback값은 감소시켰다.
The effects of alum un the physicochemical properties of non-waxy and waxy rice starches were investigated. The swelling powers of non-waxy and waxy rice starches with $0.05{sim}1.0%(w/w)$ alum were increased remarkably in comparison with rice starches without alum, but those of rice starches with alum above 1.0%(w/w) concentration were decreased slowly with the increasing amount of alum. While solubility of the non-waxy starch with $0.05{sim}1.0%(w/w)$ alum was elevated gradually with the increasing temperature. that of the waxy starch was decreased regardless temperature. But solubilities of both rice starches with alum concentration above 1.0%(w/w) exhibited no significant changes. The more alum in the system, the higher and the lower blue value were resulted in non-waxy rice starch and waxy rice starch, respectively. From amylograms, it was found that alum increased breakdown and initial pasting temperatures for both rice starches, but reduced setback.
