关键词: 富硒稻谷；加速陈化；储藏特性；糊化特性

Abstract: In order to study the pattern of quality changes in selenium-rich rice during storage, selenium-rich rice and non-selenium-rich rice produced in Enshi and Jingzhou of Hubei province were subjected to accelerated aging for 180 days under high temperature storage conditions (35 ℃, and 50% relative humidity) in an artificial climate incubator. The storage characteristics, gelatinization characteristics and edible quality were measured and analyzed every 30 days. The results showed that with increasing storage time, the trends of changes in all tested indicators were consistent between selenium-rich rice and non-selenium-rich rice, but the degree of change was different. On day 180, the germination rate of non-selenium-rich rice was 69.7% and 65.7% for the cultivars Ezhong 6 and Daojingliangyou, the content of fatty acids increased by 40.43% and 59.74% compared with those on day 0, and α-amylase activity was 0.26 and 0.22 U/g, respectively. For these two cultivars, the germination rate of selenium-rich rice was 66.7% and 64.0%, and the content of fatty acids increased by 53.99% and 78.47% compared with those on day 0, and α-amylase activity was 0.24 and 0.19 U/g, respectively. Compared with the control group, selenium-rich rice had lower germination rate, lower α-amylase activity and higher fatty acid value, indicating no obvious advantages in storage quality. On day 180, the content of malondialdehyde (MDA) was 0.36 and 0.28 μmol/g in ordinary Ezhong 6 and Daojingliangyou rice, the content of free phenols was 341.78 and 371.59 μg/g, and free sulfhydryl group content was 0.67 and 0.64 μmol/g, respectively; for selenium-enriched Ezhong 6 and Daojingliangyou rice, MDA content was 0.31 and 0.24 μmol/g, free phenol content was 368.33 and 399.22 μg/g, and free sulfhydryl group content was 0.89 and 0.74 μmol/g, respectively. Compared with the control group, selenium-rich rice had lower MDA content, and higher contents of free phenols and free sulfhydryl groups, indicating better antioxidant capacity during storage. In terms of gelatinization characteristics, texture characteristics and edible quality, compared with the control group, selenium-rich rice had higher peak viscosity, lower gelatinization temperature, lower hardness, higher viscosity, higher elasticity and higher taste score during the same storage period. In conclusion, selenium-rich rice had better antioxidant capacity and higher taste score during storage at 35 ℃, but did not show anti-aging advantages.

Key words: selenium-rich rice; accelerated aging; storage characteristics; gelatinization characteristics