Storage of brown rice and its physicochemical properties under high temperature and humidity negative air ions environment

Abstract

Brown rice is susceptible to oxidation of lipids during storage, resulting in the deterioration of cooking quality and the loss of nutrients. The negative oxygen ions (NAIs) have the functions of high permeability, antioxidation, and sterilization, but the application of NAIs for the storage of brown rice is less. In this study, brown rice is stored in a high temperature and humidity (temperature of 42 °C, humidity of 75%) NAIs environment, and its storage and physicochemical properties are investigated. After 12 d of storage in the NAIs environment (NAIs concentration of 2 × 104 ions/cm3), the fatty acid value, catalase activity, and viability of brown rice are 10.51 mg KOH/100 g, 0.94 U/mg, and 72%, respectively, which are better than that in high temperature and humidity air environment, showing good storage performance. The internal structure, crystalline shape, and relative crystallinity of brown rice are insignificant broken, and the steaming quality does not change significantly with the extension of storage time. The results show that the NAIs environment has potential to extend the storage time and maintain the eating quality and nutrition of brown rice in storage, which can be used as a green and low-cost storage strategy for crops.