title: Understanding how the aggregation structure of starch affects its gastrointestinal digestion rate and extent.
abstract: Regulating the starch gastrointestinal digestion rate by control of its aggregation structure is an effective way, but the mechanism is still not clear. Multi-scale structure of waxy and normal wheat starches were studied by confocal laser scanning and scanning electron microscopes, as well as wide-angle and small-angle X-ray techniques in this study. In vitro digestion kinetics of those two starches and structure-digestion relationship were also discussed. Both waxy and normal starches show A-type diffraction pattern, but waxy variety shows a slightly higher crystallinity. Small-angle X-ray scattering results show that waxy wheat starch has higher scattering peak intensity (Imax) and a larger crystallinity lamellar repeat distance (Lp) compared with the normal wheat starch. We suggested that the higher digestion rate of waxy starch at initial stage is mainly due to more small-size particles, but the higher crystallinity and the larger crystalline lamellar size limit the digestion extent.
authors.affiliation: School of Food Science, South China Agricultural University, Guangzhou 510642, China. Electronic address: peichen@scau.edu.cn.
authors.forename: Pei
authors.initials: P
authors.lastname: Chen
authors.affiliation: School of Food Science, South China Agricultural University, Guangzhou 510642, China.
authors.forename: Kai
authors.initials: K
authors.lastname: Wang
authors.affiliation: Institute of Food Science and Technology (IFST), Chinese Academy of Agricultural Science (CAAS), Beijing100193, China.
authors.forename: Qirong
authors.initials: Q
authors.lastname: Kuang
authors.affiliation: Institute of Food Science and Technology (IFST), Chinese Academy of Agricultural Science (CAAS), Beijing100193, China.
authors.forename: Sumei
authors.initials: S
authors.lastname: Zhou
authors.affiliation: Zhengzhou Second People's Hospital, Zhengzhou 450006, China.
authors.forename: Dazheng
authors.initials: D
authors.lastname: Wang
authors.affiliation: Institute of Food Science and Technology (IFST), Chinese Academy of Agricultural Science (CAAS), Beijing100193, China. Electronic address: ytboy652@163.com.
authors.forename: Xingxun
authors.initials: X
authors.lastname: Liu
mesh_terms: D004063:Digestion; D041981:Gastrointestinal Tract / Q000378:metabolism*; D013213:Starch / Q000737:chemistry* / Q000378:metabolism*
chemical_list: D013213:Starch
keywords: In vitro digestion properties; Multi-scale structure; Wheat starch