title: Changes in physicochemical properties of waxy corn starches at different stages of harvesting.
abstract: Starches were isolated from immature waxy corn kernels harvested at 0, 2, 4 and 6 days after optimum stage (DAO) and from mature kernels at 16 DAO. The starch contents showed varied according to genotypes and harvesting stages. The accumulation of starches showed an increasing trend in relation to delayed harvesting time, from the optimum stage until the physiological maturity stage. Among all harvesting stages, medium granules had the highest contribution to the total starch volume (60.8-81.5%), followed by large (5.7-30.1%), and small granules (9.1-15.3%). Average chain length distribution of amylopectin ranged from DP 14.7 to 16.9 for KKU-UB, DP 16.9 to 17.4 for KKU-JD, and DP 5.7 to 30.1 for Violet white. The pasting behaviors of starches were greatly affected by harvesting times. The peak viscosity of starches increased with delayed harvesting until physiological maturity and then decreased until dried kernels at 35 days after pollination.
authors.affiliation: Department of Plant Science and Agricultural Resources, Faculty of Agriculture, Khon Kaen University, Khon Kaen 40002, Thailand.
authors.forename: Danupol
authors.initials: D
authors.lastname: Ketthaisong
authors.forename: Bhalang
authors.initials: B
authors.lastname: Suriharn
authors.forename: Ratchada
authors.initials: R
authors.lastname: Tangwongchai
authors.forename: Kamol
authors.initials: K
authors.lastname: Lertrat
mesh_terms: D000688:Amylose / Q000737:chemistry; D055598:Chemical Phenomena; D005838:Genotype; D013213:Starch / Q000737:chemistry*; D014885:Waxes / Q000737:chemistry*; D003313:Zea mays / Q000737:chemistry* / Q000235:genetics / Q000254:growth & development*
chemical_list: D014885:Waxes; D013213:Starch; D000688:Amylose
keywords: Amylopectin chain length distribution; Harvesting stage; Kernel maturity; Physicochemical property; Starch granule; Waxy corn