Wang Shujun, Li Peiyan, Yu Jinglin, Guo Peng, Wang Shuo
Key Laboratory of Food Nutrition and Safety, Ministry of Education, Tianjin University of Science & Technology, Tianjin 300457, China.
Key Laboratory of Food Nutrition and Safety, Ministry of Education, Tianjin University of Science & Technology, Tianjin 300457, China.
Int J Biol Macromol. 2017 Sep;102:136-143. doi: 10.1016/j.ijbiomac.2017.04.020. Epub 2017 Apr 7.
The structural and functional properties of starches from three rice grains differing in amylose content (19.9, 13.4 and 0.8% for Japonica, Indica hybrid and waxy rice, respectively) were investigated using a range of characterization methods Indica hybrid starch (IHS) had the highest proportion of intermediate (DP 13-24) and long branch chains (DP≥37) and the lowest proportion of short branch chains (DP 6-12), whereas the opposite results were observed for Japonica starch (JS). The results for waxy rice starch (WS) were between those of IHS and JS. Rice starches showed a typical A-type X-ray diffraction pattern with the relative crystallinity ranging from 33.4% for JS to 39.4% for WS. Significant differences were observed in lamellar distance and short-range molecular order characterized by IR ratio of absorbances at 1047/1022cm and full width of half maximum (FWHM) of the band at 480cm. WS showed a higher swelling power and a lower close packing concentration at temperatures from 60 to 90°C. The lower peak viscosity of WS was attributed to the formation of less rigid swollen granules at a concentrated regime. WS showed a higher in vitro digestibility compared with IHS and JS.
使用一系列表征方法研究了三种直链淀粉含量不同的水稻籽粒淀粉的结构和功能特性（粳稻、籼稻杂交种和糯稻的直链淀粉含量分别为19.9%、13.4%和0.8%）。籼稻杂交种淀粉（IHS）的中等长度（聚合度13 - 24）和长支链（聚合度≥37）比例最高，短支链（聚合度6 - 12）比例最低，而粳稻淀粉（JS）则呈现相反的结果。糯稻淀粉（WS）的结果介于IHS和JS之间。水稻淀粉呈现典型的A型X射线衍射图谱，相对结晶度范围从粳稻淀粉的33.4%到糯稻淀粉的39.4%。通过1047/1022cm处吸光度的红外比和480cm处谱带的半高宽（FWHM）表征的层间距和短程分子有序性存在显著差异。在60至90°C的温度范围内，糯稻淀粉显示出更高的膨胀力和更低的紧密堆积浓度。糯稻淀粉较低的峰值粘度归因于在浓缩状态下形成的刚性较小的膨胀颗粒。与IHS和JS相比，糯稻淀粉显示出更高的体外消化率。
