He Hai, Zheng Bo, Wang Hongwei, Li Xiaoxi, Chen Ling
Ministry of Education Engineering Research Center of Starch & Protein Processing, Guangdong Province Key Laboratory for Green Processing of Natural Products and Product Safety, School of Food Science and Engineering, South China University of Technology, Guangzhou 510640, China.
Ministry of Education Engineering Research Center of Starch & Protein Processing, Guangdong Province Key Laboratory for Green Processing of Natural Products and Product Safety, School of Food Science and Engineering, South China University of Technology, Guangzhou 510640, China.
Food Res Int. 2020 Nov;137:109612. doi: 10.1016/j.foodres.2020.109612. Epub 2020 Aug 5.
The study presents an innovative approach using heat-moisture treatment (HMT) to prepare rice starch-oleic acid (OA)/linoleic acid (LOA) complex. Relationship of the multi-scale structure-in vitro digestibility of rice starch-OA/LOA complex induced by HMT was established in this work. Herein, HMT induced the formation of single helices complex between OA/LOA and amylose or long side chains of amylopectin, which formed more V-type crystallite. HMT assisted complexation with OA/LOA resulted in higher ordered molecular chain aggregations in amorphous amylose background area, reduced the amorphous lamellae and made the double helices and A-type crystallite perfectly arranged. These structural alternations inhibited the molecular interactions (e.g., binding ability, catalyzed location) between rice starch and α-amylase, which eventually increased the resistant starch (RS) content and decreased the slow digestible starch (SDS) content. Moreover, HMT treated rice starch formed type II complex with OA and type I complex with LOA, and all the referred changes went more obvious with the increasing amount of OA than LOA. The results suggested that the OA/LOA was inserted inside the amylose spiral cavity and the amorphous lamellae of rice starch. The current study exhibited an in-depth research of the multi-scale structure within rice starch-OA/LOA complex and proposes a promising approach to ensure the starch products have designated digestibility.
该研究提出了一种创新方法，即采用湿热处理（HMT）制备大米淀粉 - 油酸（OA）/亚油酸（LOA）复合物。本研究建立了由HMT诱导的大米淀粉 - OA/LOA复合物的多尺度结构与体外消化率之间的关系。在此，HMT诱导OA/LOA与直链淀粉或支链淀粉的长侧链之间形成单螺旋复合物，进而形成更多的V型微晶。HMT辅助OA/LOA进行络合，导致在无定形直链淀粉背景区域中分子链聚集更加有序，减少了无定形薄片，并使双螺旋和A型微晶排列完美。这些结构变化抑制了大米淀粉与α -淀粉酶之间的分子相互作用（如结合能力、催化位点），最终增加了抗性淀粉（RS）含量，降低了慢消化淀粉（SDS）含量。此外，HMT处理的大米淀粉与OA形成II型复合物，与LOA形成I型复合物，并且随着OA用量的增加，所有上述变化比LOA更明显。结果表明，OA/LOA插入到大米淀粉的直链淀粉螺旋腔和无定形薄片内部。当前研究对大米淀粉 - OA/LOA复合物的多尺度结构进行了深入研究，并提出了一种有前景的方法来确保淀粉产品具有特定的消化率。
