Abstract:

In this study, multiple molecular absorption theory, heat and mass transfer theory through porous media and stress theory were used to analyze the effect of temperature and humidity on rice hygroscopicity process and explain the reason for fissure formation. Results showed that air relative humidity affected the whole hygroscopicity progress; however, air temperature only exhibited an obvious effect on hygroscopicity on the surface of rice. Meanwhile, both temperature and relative humidity were positively correlated to the cracking rate of rice. Temperature alone was negatively related to hygroscopicity rate, whereas relative humidity was positively related to hygroscopicity.

Key words: rice, hygroscopicity, cracking, temperature, humity, B.E.T. model, heat and mass transfer theory through porous media, stress-relaxation theory