Starch Properties of Daehak Waxy Corn with Different Harvest Times

수확시기에 따른 대학찰옥수수의 전분특성

This study investigated starch properties of 'Daehak waxy corn (DWC)' with different harvest times. The DWCs were harvested at 4 days before suitable time (BST), suitable time (ST) and 4 days after suitable time (AST). As harvest time was delayed, starch yield and amylopectin content of DWC starch increased from 43.21 to 52.73%, and from 90.79 to 92.83% based on dry weight, respectively. As harvest time was postponed, enzymatic digestibility and water solubility of DWC starch decreased from 81.43 to 80.58%, and from 10.23 to 9.23%. However, water binding capacity and swelling power of DWC starch increased from 227.94 to 244.88%, and from 24.75 to 29.74%, respectively. Retrogradation viscosity of starch was the lowest in DWC harvested at AST. There was a high correlation coefficient among starch properties of DWC, such as starch yield, enzymatic digestibility, water binding capacity, swelling power, water solubility and retrogradation viscosity (p<0.01). As harvest time was deferred, enzymatic digestibility, water solubility and retrogradation viscosity decreased; however, amylopectin content increased, and water binding capacity and swelling power significantly increased with increasing amylopectin content.

대학찰옥수수의 수확시기에 따른 전분특성을 규명하기 위하여 수확적기, 전기(-4일) 및 후기(+4일) 옥수수로부터 분리된 전분의 수율, 효소적 소화율, 물결합력, 팽윤력, 용해도 및 점도를 살펴보았다. 수확시기별 대학찰옥수수 전분의 수율은 43.21~52.73% 범위로 수확시기가 늦어질수록 높게 나타났으며, 아밀로펙틴의 함량은 90.79~92.83% 범위에서 증가하였다. 수확시기가 늦어짐에 따라 전분의 효소적 소화율과 용해도는 각각 81.43에서 80.58%와 10.23에서 9.23%로 감소하였으나, 전분의 물결합력과 팽윤력은 각각 227.94에서 244.88%와 24.75%에서 29.74%로 증가하였다. 점도는 최초 측정온도인 $90^{\circ}C$에서는 큰 차이가 없었으나, 전분 겔이 노화됨에 따라 점도는 증가하였으며, 수확시기가 늦어질수록 점도는 낮게 나타났다. 전분특성 관련 인자들 사이의 상관관계를 분석한 결과 높은 양 또는 음의 상관관계를 보였으며(p<0.01), 아밀로펙틴의 함량이 높을수록 효소적 소화율, 용해도 및 노화점도는 감소하였으나, 물결합력과 팽윤력은 증가하였다.