Publication no. C-1999-1005-03R |  VIEW ARTICLE

Genetic Diversity in Physical Properties of Starch from a World Collection of Amaranthus.

Huaixiang Wu (1) and Harold Corke (1,2). (1) Cereal Science Laboratory, Department of Botany, The University of Hong Kong, Pokfulam Road, Hong Kong. (2) Corresponding author. Fax: +852 2858 3477. E-mail: <hcorke@yahoo.com> Cereal Chem. 76(6):877-883. Accepted August 11, 1999. Copyright 1999 American Association of Cereal Chemists, Inc.

Physical and functional properties of starches isolated from 93 noncultivated genotypes of nine Amaranthus species from a world germ plasm collection and an additional 31 cultivated Amaranthus genotypes obtained from China were tested. A wide variation was found in the properties tested among the Amaranthus species and among genotypes within the same species. When comparing starches from cultivated and noncultivated genotypes, it was generally found that amylose was lower; starch pasting profiles were more consistent with higher peak viscosity, lower breakdown, and lower setback; the gelatinization temperature was lower; and energy of enthalpy was higher. Under cool storage, the hardness of cultivated starch pastes was lower and the adhesiveness was higher. As expected, amylose content was a primary factor affecting the physical and functional properties of Amaranthus starch. Compared with reference maize, rice, and wheat starches, Amaranthus starch tended to have lower hot paste viscosity and lower cool paste viscosity; and higher gelatinization temperatures and higher energy of enthalpy. Furthermore, Amaranthus starch pastes showed less change of gel hardness and adhesiveness after cold storage. The environmental effect on the different properties of starch varied among Amaranthus species. It is suggested that Amaranthus starches can be developed for a wide range of food uses.