쌀전분으로부터 분리한 아밀로오스와 아밀로펙틴 혼합겔의 형태학적 구조

Microstructure of Recombinated Gels of Amylose and Amylopectin Isolated from Rice Starch

쌀전분으로부터 분리한 아밀로오스와 아밀로펙틴이겔을 형성할 수 있는 최저농도로 아밀로오스와 아밀로펙틴 혼합겔을 제조하여 주사전자현미경과 X-선 회절기를 이용하여 겔 구조를 관찰하였다. 겔을 형성할 수 있는 최저농도인 용해성 아밀로오스 1.08% 농도에 아밀로펙틴을 $1.5%{\sim}7%$ 첨가하면 겔 그물망구조가 잘 형성되었고, 아밀로펙틴을 2%와 3% 첨가한 겔은 저장에 따라 $2{\theta}\;=\;17.0^{\circ}$에서 피크가 커졌다. 15% 아밀로오스/아밀로펙틴 혼합겔을 저장했을 때 아밀로오스 함량이 높을수록 단단하고 안정된 그물망구조를 이루었으며 생전분에서의 겔형성 양상과는 달리 아밀로오스와 아밀로펙틴이 함께 겔메트릭스를 이루는데 참여하는 것으로 생각되었고, 아밀로오스 함량이 증가할수록 $2{\theta}\;=\;17.0^{\circ}$에서 피크의 크기와 결정강도는 커졌다.

The changes on microstucture of recombinated gels with different ratio of amylose(A) and amylopectin(AP) which were isolated from nonwaxy rice starch were investigated by scanning electron microscope(SEM) and X-ray diffractometer. As the concentration of amylose was above 3%(1.08% of soluble amylose) in the amylose suspension, gel matrix became like a three-dimensional network. The microstructure of amylose gels showed a network including macroporous structure, but the higher the ratio of amylopectin content were, the firmer network were formed. In case of A/AP mixed gels(15%) with different amylose/amylopectin percent ratios ; 0/5, 5/10, 10/5, 15/0%, as the storage time of gels and the percent ratio of amylose content were increased, network was formed harder with thick films. While X-ray diffractograms of waxy rice starch which contained 100% amylopectin showed A type, those of purified amylose and amylopectin showed V type and amorphous patterns, respectively. Amylose(3%) gels added $2{\sim}3%$ amylopectin and A/AP mixed gels(15%) showed peak at $2{\theta}\;=\;17.0^{\circ}$which were shown B type crystallinity similar af retrograded starches. Also as the percent ratio of amylose content in mixed gels was increased, peak intensity wat increased.