When brewing sweet wine, be sure not to dip it in salt. If there is salt in the rice, it will go bad! Another problem is that the amount of koji (we call it cake medicine) must be appropriate, not too much or too little. Generally, one tank of wine contains One and a half to two. Also, the rice cooked in cold weather should not be cold for too long before being put into the nest. It should be kept warm at all times. Generally, it should be opened in three to five days and tasted to see if it is ready. Think about what went wrong.