The University of Queensland, Centre for Nutrition and Food Sciences, Queensland Alliance for Agriculture and Food Innovation, Brisbane, QLD 4072, Australia.
The University of Queensland, Centre for Nutrition and Food Sciences, Queensland Alliance for Agriculture and Food Innovation, Brisbane, QLD 4072, Australia; Department of Chemical Engineering, Monash University, Clayton, VIC 3800, Australia.
Carbohydr Polym. 2020 Oct 1;245:116557. doi: 10.1016/j.carbpol.2020.116557. Epub 2020 Jun 4.
High-amylose wheat starch (HAWS) and flour (HAWF) have the potential to deliver food products with enhanced nutritional functionality, but structure/function relationships are not well understood. We report the structural bases for differences in water absorption and pasting properties for HAWS and HAWF (amylose contents 71-84 %) compared with wild-type (WTWS/WTWF). With higher amylose content, the proportion of longer amylopectin chains with DP > 25 increased. Both the degree of branching and the branch lengths of amylose were lower for HAWS than WTWS. Compared with WTWF, HAWF contained less total starch, more protein, had lower peak viscosity by high-temperature RVA, lower dough development time and stability time and higher water absorption by Farinograph. Water absorption by HAWS was ∼1.5 times greater than for WTWS, suggesting loose packing of polymers within HAWS granules. Consistent with this, crystallinity and birefringence of starch granules were lower in HAWS.
高直链淀粉小麦淀粉（HAWS）和面粉（HAWF）具有为食品提供增强营养功能的潜力，但结构/功能关系尚不清楚。我们报告了与野生型（WTWS/WTWF）相比，HAWS 和 HAWF（直链淀粉含量为 71-84%）在吸水性和糊化特性方面差异的结构基础。随着直链淀粉含量的增加，具有 DP > 25 的更长支链淀粉链的比例增加。HAWS 的支化度和支链长度均低于 WTWS。与 WTWF 相比，HAWF 含有较少的总淀粉，更多的蛋白质，高温 RVA 的峰值黏度较低，面团形成时间和稳定时间较短，粉质仪的吸水率较高。HAWS 的吸水率约为 WTWS 的 1.5 倍，表明 HAWS 颗粒内聚合物的松散堆积。与此一致的是，HAWS 淀粉颗粒的结晶度和双折射度较低。
