Wang Tao, She Nana, Wang Mengnan, Zhang Bo, Qin Jiaxing, Dong Jingyuan, Fang Guozhen, Wang Shuo
State Key Laboratory of Food Nutrition and Safety, Tianjin University of Science and Technology, Tianjin 300457, China.
Tianjin Key Laboratory of Food Science and Health, School of Medicine, Nankai University, Tianjin 300071, China.
Foods. 2021 Nov 2;10(11):2658. doi: 10.3390/foods10112658.
The effects of storage temperature on the physicochemical properties and qualities of red brown rice were investigated in this study. The samples were vacuum-packed in nylon/polyethylene pouches and stored at 15 °C, 25 °C and 35 °C for 12 weeks. The moisture content decreased as storage time was prolonged. Rice stored at 15 °C and 25 °C had a lower falling range of water content compared to the samples stored at 35 °C. Free fatty acid values increased fastest when samples were stored at a high temperature, and the rise can be effectively delayed at low temperatures. The pH of residual cooking water and adhesiveness decreased, while the heating water absorption rate and hardness increased during storage for red and brown rice. Low-field nuclear magnetic resonance results indicate that water molecules migrated, the binding force of H protons became stronger and the bonds between molecules became closer with increased storage duration. Temperature had an obvious correlation with starch granules and protein structure, characterized by a scanning electron microscope and Fourier transform infrared spectroscopy. Low temperatures significantly retarded those changes. The results indicate that storage temperature is a vital factor affecting the physicochemical properties and qualities of red brown rice and provided reference and theoretical basis for the actual storage of red brown rice.
本研究考察了贮藏温度对红糙米理化性质和品质的影响。样品用尼龙/聚乙烯袋真空包装，分别在15℃、25℃和35℃下贮藏12周。随着贮藏时间的延长，水分含量降低。与贮藏在35℃的样品相比，贮藏在15℃和25℃的大米水分含量下降幅度较小。样品在高温下贮藏时游离脂肪酸值增加最快，而在低温下可有效延缓其上升。红糙米和糙米在贮藏期间，残留米汤的pH值和黏性降低，而热水吸水率和硬度增加。低场核磁共振结果表明，随着贮藏时间的延长，水分子发生迁移，H质子的结合力增强，分子间的键变得更紧密。温度与淀粉颗粒和蛋白质结构有明显的相关性，通过扫描电子显微镜和傅里叶变换红外光谱进行表征。低温显著延缓了这些变化。结果表明，贮藏温度是影响红糙米理化性质和品质的重要因素，为红糙米的实际贮藏提供了参考和理论依据。
