Nakamura Sumiko, Katsura Junji, Suda Akira, Maruyama Yasuhiro, Ohtsubo Ken'ichi
Faculty of Applied Life Sciences, Niigata University of Pharmacy and Applied Life Sciences, 265-1, Higashijima, Akiha-ku, Niigata 956-8603, Japan.
NSP Ltd., Nakanoki 2-31-5-B, Funabashi-shi, Chiba 274-0826, Japan.
Foods. 2024 Jul 1;13(13):2094. doi: 10.3390/foods13132094.
Recently, global warming has led to an increase in chalky rice grains. This has consequently resulted in the deterioration in quality of rice products. Although we previously reported that hard water, rich in Ca, is useful for the quality improvement of high-temperature-damaged rice grains, the mechanism was not elucidated sufficiently. Therefore, we used various kinds of rice cultivars, from waxy to high-amylose ones, for soaking and boiling in hard water and compared physical and chemical properties of the products. It was shown that the degree of quality improvement, such as final viscosities in pasting property, and textural properties of boiled rice, was more remarkable for high-amylose rice than low-amylose rice. As we found that the phosphorus contents showed positive correlations with amylose and long chains of amylopectin, we estimate that the effects are mainly due to binding of calcium and phosphorus. Because that high-amylose or long-chain-rich amylopectin rice cultivars showed high calcium contents in rice products, these rice cultivars would be very useful to supply calcium through dietary intake via hard water cooking.
最近，全球变暖导致垩白米的数量增加。这进而导致了大米制品质量的下降。尽管我们之前报道过富含钙的硬水对改善高温受损米粒的品质有用，但其中的机制尚未得到充分阐明。因此，我们使用了从糯稻到高直链淀粉含量水稻等各种水稻品种，在硬水中浸泡和蒸煮，并比较了所得产品的物理和化学性质。结果表明，对于高直链淀粉含量的水稻，其品质改善程度，如糊化特性中的最终粘度以及米饭的质地特性，比低直链淀粉含量的水稻更为显著。由于我们发现磷含量与直链淀粉和支链淀粉的长链呈正相关，我们估计其作用主要是由于钙和磷的结合。因为高直链淀粉或富含长链支链淀粉的水稻品种在大米制品中显示出高钙含量，这些水稻品种对于通过硬水煮食的膳食摄入来补充钙将非常有用。
