School of Engineering, University of Guelph, 50 Stone Road East, Guelph, Ontario N1G 2W1, Canada; Whistler Center for Carbohydrate Research, Department of Food Science, Purdue University, 745 Agriculture Mall Drive, West Lafayette, IN 47907-2009, USA.
Whistler Center for Carbohydrate Research, Department of Food Science, Purdue University, 745 Agriculture Mall Drive, West Lafayette, IN 47907-2009, USA; Department of Food Science and Technology, The Ohio State University, 110 Parker Food Science Building, 2015 Fyffe Road, Columbus, OH 43210-1007, USA.
Carbohydr Polym. 2019 Jul 1;215:198-206. doi: 10.1016/j.carbpol.2019.03.076. Epub 2019 Mar 26.
This work provides information on the feasibility of molecular shear scissions that promote interactions resulting in slowly digestible foods. Extrusion using nine different Specific Mechanical Energy (SME) was performed to obtain amylose and amylopectin with different hydrodynamic radius (R) and molecular weight (M) from banana starch. The work also aims to find a potential size threshold that decreases starch bio-accessibility through the formation of structural assemblies. Shear-induced fragmentation enabled molecules to get in closer proximity promoting interactions that caused a 36% reduction in their digestion rate. Results suggested that the nature of the structurally-driven slowly digestible starch is mostly due to molecular interactions involving amylopectin, which do not necessarily worsen the food mechanical properties. The R and M threshold to significantly decrease starch bio-accessibility was estimated to be in the range of 54.3-58.9 nm and 9.9 × 10-17.1 × 10 g/mol, respectively, which was attained in the SME range of 177-274 kJ/kg.
这项工作提供了关于分子剪切断裂促进相互作用从而产生缓慢消化食物的可行性的信息。使用九种不同的特定机械能（SME）进行挤压，从香蕉淀粉中获得具有不同流体力学半径（R）和分子量（M）的直链淀粉和支链淀粉。该工作还旨在寻找一个潜在的尺寸阈值，通过形成结构组装来降低淀粉的生物利用度。剪切诱导的分子碎片化使它们更接近彼此，促进了相互作用，从而使它们的消化速度降低了 36%。结果表明，结构驱动的缓慢消化淀粉的性质主要归因于涉及支链淀粉的分子相互作用，这不一定会恶化食物的机械性能。估计显著降低淀粉生物利用度的 R 和 M 阈值分别在 54.3-58.9nm 和 9.9×10-17.1×10g/mol 的范围内，这是在 177-274kJ/kg 的 SME 范围内达到的。
