Degradation kinetics of physicochemical and sensory properties of rice during storage at different temperatures

Abstract

In this study, we applied Arrhenius kinetic models of physical, chemical, and sensory qualities of rice stored for 1 year at different temperatures and calculated their temperature dependence by analyzing their kinetic parameters and shelf lives. The physicochemical properties—germination rate, seed viability, and fat acidity—and the sensory properties—overall sensory quality, appearance, odor, taste, and texture—were well-fitted to Arrhenius plots (R2 > 0.90) following the first-order kinetic model. For the highest temperature differences, seed viability had the highest temperature dependence in terms of k, t1/2, D value, and shelf life, the highest Q10 and Ea, and lowest z value, followed by germination rate, all sensory characteristics, and fat acidity. Moreover, for these properties, the temperature rise led to an increased degradation rate and decreased shelf life in a logarithmic manner rather than linear. Considering overall sensory quality, shelf lives of 7.83, 2.42, and 0.82 years were observed at temperatures of 10, 20, and 30 °C, respectively. Additionally, we developed predictive equations for shelf life based on storage temperatures (R2 = 0.80–0.96). Our predictive equations and results of degradation kinetics can facilitate design and control of postharvest rice storage systems.