期刊
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
卷 62, 期 3, 页码 760-771出版社
AMER CHEMICAL SOC
DOI: 10.1021/jf404697v
关键词
starch granule ghosts; gelatinization; alpha-amylase; enzyme-resistant fraction; glucan conformation; polymer entanglement
After heating in excess water under little or no shear, starch granules do not dissolve completely but persist as highly swollen fragile forms, commonly termed granule ghosts. The macromolecular architecture of these ghosts has not been defined, despite their importance in determining characteristic properties of starches. In this study, amylase digestion of isolated granule ghosts from maize and potato starches is used as a probe to study the mechanism of ghost formation, through microstructural, mesoscopic, and molecular scale analyses of structure before and after digestion. Digestion profiles showed that neither integral nor surface proteins/lipids were crucial for control of either ghost digestion or integrity. On the basis of the molecular composition and conformation of enzyme-resistant fractions, it was concluded that the condensed polymeric surface structure of ghost particles is mainly composed of nonordered but entangled amylopectin (and some amylose) molecules, with limited reinforcement through partially ordered enzyme-resistant structures based on amylose (for maize starch; V-type order) or amylopectin (for potato starch; B-type order). The high level of branching and large molecular size of amylopectin is proposed to be the origin for the unusual stability of a solid structure based primarily on temporary entanglements.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据