Abstract The effects of thermomechanical treatment and guar gum (GG) addition on the in vitro digestibility of rice starch have been investigated. Rice starch added with GG at concentrations of 0, 0.025, 0.05, 0.075, or 0.10 g/100 g (wet basis) was subject to a micro-extrusion process. The in vitro digestibility, predicted glycemic index (pGI), and multi-scale structures (granule, lamellar, crystalline, and molecular structures) were examined. Micro-extruded rice starch (MERS) with GG presented reduced digestion rate and pGI, a higher degree of structural ordering, and altered crystalline, single-helical and double-helical structures. Using Pearson correlation analysis, the relationships among extrusion, the molecular interaction and multi-scale structure, and the digestibility were established. The content of resistant components (RC) was positively correlated with crystallinity (r = 0.836, p

中文翻译：

---

热机械辅助与瓜尔胶络合提高大米淀粉体外消化率

摘要 研究了热机械处理和瓜尔胶 (GG) 添加对大米淀粉体外消化率的影响。添加浓度为 0、0.025、0.05、0.075 或 0.10 g/100 g（湿基）的 GG 的大米淀粉进行微挤压工艺。检查了体外消化率、预测血糖指数 (pGI) 和多尺度结构（颗粒、层状、结晶和分子结构）。含 GG 的微挤压大米淀粉 (MERS) 降低了消化率和 pGI，结构有序度更高，并改变了晶体、单螺旋和双螺旋结构。通过Pearson相关分析，建立了挤出、分子相互作用和多尺度结构与消化率之间的关系。