Rice storage under controlled conditions: Changes in its physicochemical and functional properties

Abstract

Rice storage is necessary to improve cooked rice's textural and functional characteristics. Storage conditions affect the quality of rice. Fresh rice samples with low amylose content (≈10%) were stored for 6 months at different temperatures (2) and air availability (3) to evaluate their individual and synergic effect on rice quality. Chemical composition, rice texture, cooking, thermal properties, water uptake, and texture after cooking were analyzed at 2-month intervals. The results showed that storage temperature, time, and the interaction between them significantly affected stored rice's hardness, water uptake, solid loss, and gelatinization temperatures. Higher air availability resulted in an increase in hardness and Amylose-Lipid (A-L) complexing index. The A-L complexing index increased with storage time, predominately when the rice samples were kept at higher temperatures. Also, this complex was positively correlated with the hardness of the cooked grain (r = 0.81) and its water absorption capacity (r = 0.90), suggesting that the A-L complex formation improves rice quality characteristics. A better rice quality was found at 23 °C with air restriction and 180 storage days.