Group for Cereals and Oils Processing, College of Food Science and Technology, Key Laboratory of Environment Correlative Dietology (Ministry of Education), Huazhong Agricultural University, Wuhan 430070, China.
Research Institute for Kitchen Small Appliances, Department of Home Appliance Technology Research, Gree Electric Appliances, Inc. of Zhuhai Co., Ltd., Zhuhai 519070, China.
Int J Biol Macromol. 2020 Feb 1;144:373-379. doi: 10.1016/j.ijbiomac.2019.12.095. Epub 2019 Dec 13.
This work concerns the multi-scale structures and digestion behaviors of indica rice starches with apparent amylose contents (AACs) of ca. 14%-24%. A higher AAC not always allowed a lower digestion rate (k), different from previous findings that starches containing more amylose normally show slowed digestion. Here, the proportion of stable molecular orders (melting temperature above ca. 73 °C) and AAC synergistically governed starch digestion rate. With a similar AAC, a higher amount of stable orders (R, ratio of enthalpy of stable orders to that of the rest) led to a lower k. Also, with a similar R, a larger AAC caused a lower k. Consistently, JPZ starch had almost the highest AAC and R, showing the lowest k. Regarding this, amylose and stable orders played roles in increasing the bulk density of starch structure matrices, and eventually slow the diffusion, absorption and catalysis events of digestion enzymes within the matrices.
这项工作研究了直链淀粉含量（AAC）约为 14%-24%的籼稻淀粉的多尺度结构和消化行为。较高的 AAC 并不总是意味着较低的消化速率（k），与之前的发现不同，通常含有更多直链淀粉的淀粉表现出较慢的消化。在这里，稳定分子有序性（熔点高于约 73°C）的比例和 AAC 协同控制淀粉消化速率。在 AAC 相似的情况下，更多的稳定有序性（R，稳定有序性的焓与其余部分的焓之比）会导致 k 降低。同样，在 R 相似的情况下，较大的 AAC 会导致 k 降低。一致地，JPZ 淀粉具有几乎最高的 AAC 和 R，表现出最低的 k。关于这一点，直链淀粉和稳定有序性在增加淀粉结构基质的堆积密度方面发挥了作用，最终减缓了基质内部消化酶的扩散、吸收和催化事件。
