새로 개발된 유색고구마인 단자미와 호감미로부터 분리한 전분의 이화학적 특성

Abstract

Purpose: The physicochemical characteristics of starches purified from newly developed sweet potato cultivars, purple fleshed Danjami and orange fleshed Hogammi were examined to determine the processing quality and suitability for food products. Methods: The starch was isolated using the alkaline steeping method. The physicochemical, pasting, and thermal properties; morphology and crystallinity were investigated. Results: The amylose contents of Danjami and Hogammi starches were 26.77% and 27.37%, respectively, but the swelling power of Danjami starch was lower than that of Hogammi starch (p<0.05). The shape of the starch Danjammi and Hogammi granules were round, polygonal, with an average granule size of 11.86 μm and 11.70 μm, respectively. The initial pasting temperature of Danjami starch (76.75°C) was significantly higher than that of Hogammi starch (71.05°C), and the trough, final viscosities of Danjami starch were higher than those of Hogammi starch (p<0.05). The Danjami starch showed a single endotherm, whereas the Hogammi starch showed a biphasic endotherm with two peak temperatures. The difference between the onset temperature and conclusion temperature (△T) was higher in Hogammi starch than in Danjami starch. The two starches exhibited all Cb type crystallinity according to x-ray diffraction. Conclusion: The Danjami and Hogammi sweet potato starches have similar physicochemical properties, but different pasting properties, which might be caused the difference in the molecular structure of the starch.