Physico-chemical Properties of Acetylated Rice Starches

초산 쌀전분의 이화학적 특성

Physico-chemical properties of the acetylated and raw starch were Investigated with the chucheongbyeo and samkangbyeo. The solubility and swelling power was increased by acylation reaction. The light transmittance was higher in the acetylated rice starch. The blue value of chucheongbyeo and samkangbyeo rice starches were lowered to 10.9% and 16.0%, respectively, by the acylation reaction. The alkali number was 7.6 in the chucheongbyeo rice starch and 7.2 in the samkangbyeo rice starch, whereas acylated starch in the same orders was 55 and 52, respectively. The hardness, adhesion, cohesion of starch gel was increased by the acylation reaction. The temperature of initial gelatinization of the acetylated chucheongbyeo and samkangbyeo rice starch was shown to $59^{\circ}C\;and\;62^{\circ}C$, respectively, lowering $5{\sim}6^{\circ}C$ in temperature by the acylation. The viscosity as well as by the acylation reaction was raised 38% and 14%, respectively. The rice starch particles were shown to plygonal structure. But it were deformed in the acylated starch, and was completely destroyed in the starch which is by gelatinized for 30 min. at $70^{\circ}C$.

추청벼와 삼강벼를 원료로 하여 전분을 제조하고 그 전분을 이용하여 초산 쌀 전분을 제조하여 얻어진 초산 쌀 전분의 이화학적 성질을 검토하여 다음과 같은 결과를 얻었다. 초산 쌀 전분의 용해도와 팽윤력은 원료 전분에 비하여 높았으며 품종간에 약간의 차이를 나타내었다. 광투과도는 원료 전분에 비하여 높았으며 원료 전분은 $60^{\circ}C$, 초산 쌀 전분은 $50^{\circ}C$부터 증가하기 시작하였으며, blue value는 원료 전분보다 낮게 나타났다. alkali number는 원료 전분보다 약 7배 높았으며, 초산 쌀 전분 겔의 경도, 응집성, 접착성, 점착성 및 저작성은 원료 전분 겔보다 높았으며 품종간에 약간의 차이를 나타내었다. Amylograph에 의한 초산 추청 및 삼강벼 전분의 호화개시온도는 각각 $59^{\circ}C,\;62^{\circ}C$ 로서 초산 처리에 의해 $5{\sim}6^{\circ}C$ 낮아졌고, 초산 쌀 전분의 점도는 원료 전분에 비하여 $14{\sim}38%$ 증가하였으며 추청벼 전분이 삼강벼 전분보다 높았다. 초산 쌀 전분 입자의 표면구조는 원료 전분에 비하여 다소 팽윤되어 헝클어진 형태를 나타냈으며, $70^{\circ}C$ 30분 가열에 의해서 완전히 붕괴되었다.