State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, Jiangsu Province, People's Republic of China; School of Food Science and Technology, Jiangnan University, Wuxi 214122, Jiangsu Province, People's Republic of China; Collaborative Innovation Center of Food Safety and Quality Control, Jiangnan University, Wuxi 214122, Jiangsu Province, People's Republic of China.
State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, Jiangsu Province, People's Republic of China; School of Food Science and Technology, Jiangnan University, Wuxi 214122, Jiangsu Province, People's Republic of China; Collaborative Innovation Center of Food Safety and Quality Control, Jiangnan University, Wuxi 214122, Jiangsu Province, People's Republic of China.
Int J Biol Macromol. 2019 Oct 1;138:966-974. doi: 10.1016/j.ijbiomac.2019.07.166. Epub 2019 Jul 26.
In the present study, we investigated the effects of complexing temperatures (75 °C and 95 °C) and oleic acid (OA) content (2%, 6%, 10% and 14%, w/w, dry basis of starch) on the structure and in vitro digestibility of maize starch-OA complexes. The resistant starch content, complexing index, thermal transition temperatures, enthalpy change and relative crystallinity of the complexes prepared at 75 °C were higher than those of corresponding complexes prepared at 95 °C. Additionally, starch-10% OA complexes prepared at 75 °C had the highest resistant starch content (18.82%), complexing index (78.83%) and relative crystallinity (14.62%). Fourier transform infrared spectroscopy revealed that the intermolecular interactions between starch and OA were affected by the complexing temperatures and OA content. Raman spectroscopy indicated that the starch-10% OA complexes prepared at 75 °С had a greater short-range molecular order than other complexes. The V-type complexes were further confirmed as V polymorph structures according to the spectra obtained by nuclear magnetic resonance spectroscopy. Therefore, we conclude that complexing temperatures and OA content greatly changed the fine structure of the complexes, which further affected their digestibility.
在本研究中，我们研究了络合温度（75°C 和 95°C）和油酸（OA）含量（2%、6%、10%和 14%，w/w，干基淀粉）对玉米淀粉-OA 络合物结构和体外消化性的影响。在 75°C 下制备的复合物的抗性淀粉含量、络合指数、热转变温度、焓变和相对结晶度均高于在 95°C 下制备的相应复合物。此外，在 75°C 下制备的淀粉-10%OA 复合物具有最高的抗性淀粉含量（18.82%）、络合指数（78.83%）和相对结晶度（14.62%）。傅里叶变换红外光谱表明，淀粉和 OA 之间的分子间相互作用受到络合温度和 OA 含量的影响。拉曼光谱表明，在 75°C 下制备的淀粉-10%OA 复合物具有比其他复合物更大的短程分子有序性。根据核磁共振光谱获得的光谱，进一步证实了 V 型复合物为 V 型多晶结构。因此，我们得出结论，络合温度和 OA 含量极大地改变了复合物的精细结构，进而影响了它们的消化性。
