The vacuum rice cooker is pressure-maintaining. When the pressure in the pot rises, the heating power supply will be turned off to maintain the pressure. However, as the pressure and temperature in the pot drop to the set value, it will automatically be electrified again, and the bottom cutting will not stop until the set time. At this time, if the power is unplugged, the food will be cooked, but it may not be very cooked, or it may be a kind of hard cooking.