Hello friends, I have discovered a trick that some way, somehow may have a scientific basis on keeping your steamed rice unspoiled for longer. After cooking, I use to leave it warm in the cold till rice cooker with the lid on top. There is something in the aluminum and steel alloy cover that makes it more prone to hold a greater amount of water vapor that later on makes the rice moist - because this water vapor drops down to the rice then soon will spoil it.