1. To prevent food spoilage, the food that is eaten at noon that day is best done in the morning, and the temperature of the prepared meals is lowered and then put into the heat preservation bucket. If the unit has a refrigerator, the food is best kept in the refrigerator. refrigeration.2. The food taken out of the freezer should be heated to 100 degrees Celsius to be eaten. After the hot food is eaten in 2 to 3 hours, it will be stored in normal temperature for more than three hours, and the bacteria will multiply easily. There are symptoms such as diarrhea and vomiting.