title: Impact of germination on the structures and in vitro digestibility of starch from waxy brown rice.
abstract: The in vitro digestibility as well as the molecular and crystalline structures of waxy rice starches isolated from brown rice, germinated brown rice (GBR), ultrasonicated GBR, and heat-moisture treated GBR were investigated. The germinated brown rice starch (GBRS) had a lower average molecular weight and a higher proportion of DP 6-12 in amylopectin than brown rice starch (BRS). The relative crystallinity, intensity ratio of the band at 1,047 cm(-1) and 1,022 cm(-1), gelatinization temperature and pasting temperature of waxy rice starch were reduced by germination. However, the ultrasonication and heat-moisture treatment of GBRS increased the relative crystallinity and gelatinization temperature. The digestibility of starch from brown waxy rice was increased by germination. The rapidly digestible starch (RDS), slowly digestible starch (SDS) and resistant starch (RS) contents were 50.5%, 42.4%, and 7.1% in BRS, and 69.0%, 27.9% and 3.1% in GBRS, respectively. The ultrasonication and heat-moisture treatment of GBRS reduced RDS content and increased RS content in raw and gelatinized starches. The decrease in starch digestibility of cooked GBR was more pronounced after heat-moisture treatment than after ultrasonication.
authors.affiliation: Division of Food and Nutrition, Chonnam National University, 77 Yongbong-ro, Buk-gu, Gwangju 500-757, Republic of Korea.
authors.forename: Su-Yeon
authors.initials: SY
authors.lastname: You
authors.affiliation: National Institute of Crop Science, Rural Development Administration, 54 Seoho-ro, Gwonseon-gu, Suwon-si, Gyonggi 441-853, Republic of Korea.
authors.forename: Sea-Gwan
authors.initials: SG
authors.lastname: Oh
authors.affiliation: National Academy of Agricultural Science, Rural Development Administration, 166 Nongsaengmyeong-ro, Iseo-myeon, Wanju-gun, Jeollabuk 565-851, Republic of Korea.
authors.forename: Hye Min
authors.initials: HM
authors.lastname: Han
authors.affiliation: Division of Food and Nutrition, Chonnam National University, 77 Yongbong-ro, Buk-gu, Gwangju 500-757, Republic of Korea.
authors.forename: Wujin
authors.initials: W
authors.lastname: Jun
authors.affiliation: Division of Food and Nutrition, Chonnam National University, 77 Yongbong-ro, Buk-gu, Gwangju 500-757, Republic of Korea.
authors.forename: Young-Shick
authors.initials: YS
authors.lastname: Hong
authors.affiliation: Division of Food and Nutrition, Chonnam National University, 77 Yongbong-ro, Buk-gu, Gwangju 500-757, Republic of Korea. Electronic address: hchung@jnu.ac.kr.
authors.forename: Hyun-Jung
authors.initials: HJ
authors.lastname: Chung
mesh_terms: D000687:Amylopectin / Q000737:chemistry; D018525:Germination; D006868:Hydrolysis; D015394:Molecular Structure; D008970:Molecular Weight; D012275:Oryza / Q000737:chemistry* / Q000254:growth & development*; D013213:Starch / Q000737:chemistry* / Q000302:isolation & purification / Q000648:ultrastructure; D013816:Thermodynamics; D014961:X-Ray Diffraction
chemical_list: D013213:Starch; D000687:Amylopectin
keywords: Germination; Physicochemical properties; Waxy brown rice starch