Post-harvest Changes in the Respiratory Activity of and Ethanol Accumulation in Fresh Rice Grains

抄録

Fresh rice grains stored under anaerobic conditions at 4°C showed a strong activity of anaerobic respiration at 30°C. Whenstored at 30°C, the rates of both oxygen consumption and carbon dioxide evolution declined rapidly. The ethanol content in paddy at the post-harvest stage was increased at 4°C, whereas no significant accumulation of ethanol was observed at 30°C. The accumulated ethanol in paddy was depleted as the storage temperature was raised from 4 to 30°C. In contrast, a temperature-dependent accumulation was observed with a lowering from 30 to 4°C. On the other hand, ethanol content in brown rice changed little with storage temperature. On the basis of these results, it is assumed that ethanol is more easily accumulated in the rice grains against diffusion to the atmosphere at the lower temperature.