Location: Corn Insects and Crop Genetics ResearchTitle: Characterization and development mechanism of Apios americana tuber starch Author
|Yangcheng, Hanyu - Iowa State University|
|Belamkar, Vikas - Iowa State University|
|Jane, Jay-lin - Iowa State University|
Submitted to: Carbohydrate Polymers
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/18/2016
Publication Date: 5/19/2016
Citation: Yangcheng, H., Belamkar, V., Cannon, S.B., Jane, J. 2016. Characterization and development mechanism of Apios americana tuber starch. Carbohydrate Polymers. 151:198-205. doi:10.1016/j.carbpol.2016.05.062.
Interpretive Summary: A native North American bean relative, Apios americana (sometimes called "potato bean" or "ground nut"), was once a staple crop of Native American Indians. This plant produces edible, nutritious, potato-like tubers, rich in starch and protein. This paper reports the physical and chemical characteristics of the starch in Apios tubers, concluding that the starch is generally similar to that in maize (corn), but that it differs in younger and older tubers, with starch grains from older tubers being larger, and slower to break down during cooking. The starch in cooked tubers (young or old) should be as nutritionally accessible as that in maize. This characterization of starch in Apios is an important step in evaluating Apios as a crop and a food source.
Technical Abstract: Apios americana is a wild legume-bearing plant with edible tubers. Domestication of Apios is in progress because of the superior nutritional value and health benefits of the tuber. Objectives of this study were to: 1) characterize physicochemical properties of Apios-tuber starch; and 2) understand differences in starch structures and properties between the mother (seed) and child (progeny) tubers and the mechanism of starch development. Granules of the Apios-tuber starch displayed spherical or ellipsoidal shape with diameter ranges of 1-30 µm. The mother-tuber starches displayed greater percentage-crystallinity, larger gelatinization enthalpy-changes, longer branch-chain lengths of amylopectin, and lower pasting viscosity than their counterpart child-tuber starches. The mother-tuber starch of Apios 2127 showed distinct two peaks of gelatinization, which were attributed to starch granules located at different regions of the tuber having different structures and properties. The mother tuber displayed more vigorous starch biosynthesis in the peripheral region than in the central region of the tuber.